Doxidization, reformat

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1469 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

src/arch/i386/lib/cpu_reset.inc

@@ -1,6 +1,9 @@
+/* -*- asm -*- */
+
 jmp cpu_reset_out
 
 __cpu_reset:
+	/* set the boot_complete flag */
 	movl	$0xffffffff, %ebp
 	jmp	__main
 

src/boot/hardwaremain.c

@@ -37,9 +37,6 @@ it with the version available from LANL.
 #include <device/pci.h>
 #include <device/chip.h>
 #include <delay.h>
-#if 0
-#include <part/mainboard.h>
-#endif
 #include <part/hard_reset.h>
 #include <smp/atomic.h>
 #include <boot/elf.h>
@@ -81,6 +78,12 @@ static struct mem_range *get_ramsize(void)
 /* Number of cpus that are currently running in linuxbios */
 static atomic_t active_cpus = ATOMIC_INIT(1);
 
+/**
+ * @brief Initialize secondary processors.
+ *
+ *
+ * @todo move this into a method of per cpu data structure.
+ */
 void secondary_cpu_init(void)
 {
 	struct mem_range *mem;
@@ -88,12 +91,14 @@ void secondary_cpu_init(void)
 	int index;
 
 	atomic_inc(&active_cpus);
+
 	printk_debug("%s\n", __FUNCTION__);
 	mem = get_ramsize();
 	id = cpu_initialize(mem);
 	index = processor_index(id);
 	printk_debug("%s  %d/%u\n", __FUNCTION__ , index, id);
 	processor_map[index] = CPU_ENABLED;
+
 	atomic_dec(&active_cpus);
 	stop_cpu(id);
 }
@@ -105,20 +110,22 @@ static void wait_for_other_cpus(void)
 	old_active_count = 1;
 
 	active_count = atomic_read(&active_cpus);
-	while(active_count > 1) {
+	while (active_count > 1) {
 		if (active_count != old_active_count) {
-			printk_info("Waiting for %d CPUS to stop\n", active_count);
+			printk_info("Waiting for %d CPUS to stop\n",
+				    active_count);
 			old_active_count = active_count;
 		}
 		active_count = atomic_read(&active_cpus);
 	}
-	for(i = 0; i < CONFIG_MAX_CPUS; i++) {
+
+	for (i = 0; i < CONFIG_MAX_CPUS; i++) {
 		if (!(processor_map[i] & CPU_ENABLED)) {
 			printk_err("CPU %d did not initialize!\n", i);
 			processor_map[i] = 0;
-#warning "FIXME do I need a mainboard_cpu_fixup function?"
 		}
 	}
+
 	printk_debug("All AP CPUs stopped\n");
 }
 
@@ -126,20 +133,16 @@ static void wait_for_other_cpus(void)
 #define wait_for_other_cpus() do {} while(0)
 #endif /* CONFIG_SMP */
 
+/**
+ * @brief Main program of LinuxBIOS
+ *
+ * @param boot_complete
+ */
 void hardwaremain(int boot_complete)
 {
 	/* Processor ID of the BOOT cpu (i.e. the one running this code) */
 	unsigned long boot_cpu;
 	int boot_index;
-
-	/* the order here is a bit tricky. We don't want to do much of 
-	 * anything that uses config registers until after PciAllocateResources
-	 * since that function also figures out what kind of config strategy
-	 * to use (type 1 or type 2). 
-	 * so we turn on cache, then worry about PCI setup, then do other 
-	 * things, so that the other work can use the PciRead* and PciWrite*
-	 * functions. 
-	 */
 	struct mem_range *mem, *tmem;
 	struct lb_memory *lb_mem;
 	unsigned long totalmem;
@@ -153,8 +156,8 @@ void hardwaremain(int boot_complete)
 	
 	post_code(0x39);
 	printk_notice("LinuxBIOS-%s%s %s %s...\n", 
-		linuxbios_version, linuxbios_extra_version, linuxbios_build,
+		      linuxbios_version, linuxbios_extra_version,
-		(boot_complete)?"rebooting":"booting");
+		      linuxbios_build, (boot_complete)?"rebooting":"booting");
 
 	post_code(0x40);
 
@@ -162,57 +165,68 @@ void hardwaremain(int boot_complete)
 	if (boot_complete) {
 		hard_reset();
 	}
+
 	CONFIGURE(CONF_PASS_PRE_PCI);
 
-	/* pick how to scan the bus. This is first so we can get at memory size. */
+	/* determine how software can generate PCI configuration transactions
+	 * in this system  */
 	printk_info("Finding PCI configuration type.\n");
 	pci_set_method();
 	post_code(0x5f);
+
+	/* convert static device structures into dynamic device structures
+	 * before probing dynamic devices. */
 	enumerate_static_devices();
+
+	/* probe the existence of dynamic devices and construct the dynamic
+	 * device tree. */
 	dev_enumerate();
 	post_code(0x66);
-	/* Now do the real bus.
+
-	 * We round the total ram up a lot for thing like the SISFB, which 
+	/* probe and assign the resources required by the dynamic devices */
-	 * shares high memory with the CPU. 
-	 */
 	dev_configure();
 	post_code(0x88);
 
+	/* enable the resources probed and assigned in dev_configure() */
 	dev_enable();
 
+	/* do the device specific init in additional to simple resources
+	 * allocation performed in dev_enable() */
 	dev_initialize();
 	post_code(0x89);
 
 	CONFIGURE(CONF_PASS_POST_PCI);
 
+	/* this is done last because some devices may 'steal' memory from
+	 * the system during device initialization. */
 	mem = get_ramsize();
 	post_code(0x70);
-	totalmem = 0;
+	for (totalmem = 0, tmem = mem; tmem->sizek; tmem++) {
-	for(tmem = mem; tmem->sizek; tmem++) {
 		totalmem += tmem->sizek;
 	}
-	printk_info("totalram: %ldM\n", 
+	/* Round to the nearest mega */
-		(totalmem + 512) >> 10); /* Round to the nearest meg */
+	printk_info("totalram: %ldM\n", (totalmem + 512) >> 10);
 
-	/* Fully initialize the cpu before configuring the bus */
+	/* fully initialize the boot processor */
 	boot_cpu = cpu_initialize(mem);
 	boot_index = processor_index(boot_cpu);
 	printk_spew("BOOT CPU is %d\n", boot_cpu);
 	processor_map[boot_index] = CPU_BOOTPROCESSOR|CPU_ENABLED;
 
-	/* Now start the other cpus initializing 
+	/* start up other processors, it works like a pthread_create() or
-	 * The sooner they start the sooner they stop.
+	 * fork(), instead of running the initialization code for all devices
-	 */
+	 * as the boot processor, they start from secondary_cpu_init(), doing
+	 * cpu initialization only. */
 	post_code(0x75);
 	startup_other_cpus(processor_map);
-	post_code(0x77);
 
-	/* make certain we are the only cpu running in linuxBIOS */
+	/* like pthread_join() or wait(), wait other processors finishing
+	 * their execution of secondary_cpu_init() and make certain we are
+	 * the only cpu running in LinuxBIOS */
 	wait_for_other_cpus();
 
-	/* Now that we have collected all of our information
+	/* Now that we have collected all of our information, write our
-	 * write our configuration tables.
+	 * configuration tables. */
-	 */
 	lb_mem = write_tables(mem, processor_map);
 
 	CONFIGURE(CONF_PASS_PRE_BOOT);

src/config/Options.lb

@@ -717,6 +717,11 @@ define HAVE_ACPI_TABLES
 	comment "Define to build ACPI tables"
 end
 
+define AGP_APERTURE_SIZE
+	default none
+	export used
+	comment "AGP graphics virtual memory aperture size"
+end
 
 ###############################################
 # Board specific options

src/cpu/k8/Config.lb

@@ -1,3 +1,6 @@
+# How does the config tool pick the correct
+# cpufixup.c to generate cupfixup.o ?
+
 uses k8
 uses CPU_FIXUP
 default k8=1

src/cpu/k8/cpufixup.c

@@ -428,5 +428,5 @@ void k8_enable(struct chip *chip, enum chip_pass pass)
 
 struct chip_control cpu_k8_control = {
         .enable = k8_enable,
-        .name   = "AMD K8",
+        .name   = "AMD K8 CPU",
 };

src/cpu/k8/earlymtrr.c

@@ -27,13 +27,24 @@ static void early_mtrr_init(void)
 	msr_t msr;
 	const unsigned long *msr_addr;
 
+	/* Enable the access to AMD RdDram and WrDram extension bits */
+	msr = rdmsr(SYSCFG_MSR);
+	msr.lo |= SYSCFG_MSR_MtrrFixDramModEn;
+	wrmsr(msr);
+
 	/* Inialize all of the relevant msrs to 0 */
 	msr.lo = 0;
 	msr.hi = 0;
-	for(msr_addr = mtrr_msrs; *msr_addr; msr_addr++) {
+
+	for (msr_addr = mtrr_msrs; *msr_addr; msr_addr++) {
 		wrmsr(*msr_addr, msr);
 	}
 
+	/* Disable the access to AMD RdDram and WrDram extension bits */
+	msr = rdmsr(SYSCFG_MSR);
+	msr.lo &= ~SYSCFG_MSR_MtrrFixDramModEn;
+	wrmsr(msr);
+
 	/* Enable memory access for 0 - 1MB using top_mem */
 	msr.hi = 0;
 	msr.lo = ((CONFIG_LB_MEM_TOPK << 10) + TOP_MEM_MASK) & ~TOP_MEM_MASK;

src/cpu/k8/earlymtrr.inc

@@ -13,6 +13,13 @@ earlymtrr_start:
 	xorl	%edx, %edx			#
 	movl	$fixed_mtrr_msr, %esi
 
+enable_fixed_mtrr_dram_modify:
+	/* Enable the access to AMD RdDram and WrDram extension bits */
+	movl	$SYSCFG_MSR, %ecx
+	rdmsr
+	orl	$SYSCFG_MSR_MtrrFixDramModEn, %eax
+	wrmsr
+		
 clear_fixed_var_mtrr:
 	lodsl	(%esi), %eax
 	testl	%eax, %eax
@@ -25,7 +32,14 @@ clear_fixed_var_mtrr:
 	jmp	clear_fixed_var_mtrr
 clear_fixed_var_mtrr_out:
 
-/* enable memory access for 0 - 1MB using top_mem */
+disable_fixed_mtrr_dram_modify:
+	/* Disable the access to AMD RdDram and WrDram extension bits */
+	movl	$SYSCFG_MSR, %ecx
+	rdmsr
+	andl	$(~SYSCFG_MSR_MtrrFixDramModEn), %eax
+	wrmsr
+
+	/* enable memory access for 0 - 1MB using top_mem */
 	movl	$TOP_MEM, %ecx
 	xorl	%edx, %edx
 	movl	$(((CONFIG_LB_MEM_TOPK << 10) + TOP_MEM_MASK) & ~TOP_MEM_MASK) , %eax
@@ -72,9 +86,10 @@ enable_mtrr:
 	movl	$0x00000800, %eax
 	wrmsr
 
-	/* Enable the MTRRs in SYSCFG */
+	/* Enable the MTRRs and IORRs in SYSCFG */
 	movl	$SYSCFG_MSR, %ecx
 	rdmsr
+	/* Don't enable SYSCFG_MSR_MtrrFixDramEn) untill we have done with VGA BIOS */
 	orl	$(SYSCFG_MSR_MtrrVarDramEn), %eax
 	wrmsr
 

src/cpu/p6/mtrr.c

@@ -99,7 +99,7 @@ static void intel_set_var_mtrr(unsigned int reg, unsigned long basek, unsigned l
 	base.hi = basek >> 22;
 	base.lo  = basek << 10;
 
-       //printk_debug("ADDRESS_MASK_HIGH=%#x\n", ADDRESS_MASK_HIGH);
+	//printk_debug("ADDRESS_MASK_HIGH=%#x\n", ADDRESS_MASK_HIGH);
 
 	if (sizek < 4*1024*1024) {
 		mask.hi = ADDRESS_MASK_HIGH;
@@ -219,7 +219,7 @@ static void set_fixed_mtrrs(unsigned int first, unsigned int last, unsigned char
 	unsigned int fixed_msr = NUM_FIXED_RANGES >> 3;
 	msr_t msr;
 	msr.lo = msr.hi = 0; /* Shut up gcc */
-	for(i = first; i < last; i++) {
+	for (i = first; i < last; i++) {
 		/* When I switch to a new msr read it in */
 		if (fixed_msr != i >> 3) {
 			/* But first write out the old msr */
@@ -304,12 +304,12 @@ void setup_mtrrs(struct mem_range *mem)
 	printk_debug("\n");
 	/* Initialized the fixed_mtrrs to uncached */
 	printk_debug("Setting fixed MTRRs(%d-%d) type: UC\n", 
-		0, NUM_FIXED_RANGES);
+		     0, NUM_FIXED_RANGES);
 	set_fixed_mtrrs(0, NUM_FIXED_RANGES, MTRR_TYPE_UNCACHEABLE);
 
 	/* Now see which of the fixed mtrrs cover ram.
 	 */
-	for(memp = mem; memp->sizek; memp++) {
+	for (memp = mem; memp->sizek; memp++) {
 		unsigned int start_mtrr;
 		unsigned int last_mtrr;
 		start_mtrr = fixed_mtrr_index(memp->basek);
@@ -317,11 +317,17 @@ void setup_mtrrs(struct mem_range *mem)
 		if (start_mtrr >= NUM_FIXED_RANGES) {
 			break;
 		}
+
+#if defined(k7) || defined(k8)
+#warning "FIXME: dealing with RdMEM/WrMEM for Athlon/Opteron"
+#endif
+
 		printk_debug("Setting fixed MTRRs(%d-%d) type: WB\n",
-			start_mtrr, last_mtrr);
+			     start_mtrr, last_mtrr);
 		set_fixed_mtrrs(start_mtrr, last_mtrr, MTRR_TYPE_WRBACK);
 	}
 	printk_debug("DONE fixed MTRRs\n");
+
 	/* Cache as many memory areas as possible */
 	/* FIXME is there an algorithm for computing the optimal set of mtrrs? 
 	 * In some cases it is definitely possible to do better.

src/devices/chip.c

@@ -9,8 +9,22 @@
 #include <device/chip.h>
 #include <device/pci.h>
 
-void
+/**
-chip_configure(struct chip *root, enum chip_pass pass)
+ * @brief Configure static devices
+ *
+ * Starting from the static device 'root', walk the tree and configure each
+ * device by calling the device specific chip_control::enable().
+ *
+ * This function is only an iterator, the exact definition of 'configure'
+ * depends on the device specific implementation of chip_control::enable(). 
+ *
+ * @param root root of the static device tree to be configured.
+ * @param pass pass of the configuration operation to be perfromed.
+ *
+ * @see chip_pass
+ * @see chip_control::enable
+ */  
+void chip_configure(struct chip *root, enum chip_pass pass)
 {
 	struct chip *c;
 
@@ -25,24 +39,37 @@ chip_configure(struct chip *root, enum chip_pass pass)
 	}
 }
 
-/** Convert a static struct chip structure to a set of dynamic device structures.
+/**
- * @param chip Static chip structure to start with.
+ * @brief Convert static device structures to dynamic structures.
+ *
+ * A static device may contain one or more dynamic devices. Dynamic device
+ * structures of these devices have to be generated before the enumeration
+ * of dynamic devices. This function converts a static chip structure to a
+ * set of dynamic device structures.
+ *
+ * This function is the generic method called by enumerate_static_device_chain()
+ * for static devices. Devices extend this default behavior by defining their
+ * own chip_controll::enumerate(). Generally, device specific
+ * chip_control::enumerate() method calls this function as its last operation.
+ *
+ * @param chip static chip structure to be converted.
+ *
  */
-
 void chip_enumerate(struct chip *chip)
 {
 	struct chip *child;
 	device_t dev;
 	int link;
 	int i;
+
 	dev = 0;
 	link = 0;
-#if 1
+
 	if (chip->control && chip->control->name) {
 		printk_debug("Enumerating: %s\n", chip->control->name);
 	}
-#endif
+
-	for(i = 0; i < MAX_CHIP_PATHS; i++) {
+	for (i = 0; i < MAX_CHIP_PATHS; i++) {
 		int identical_paths;
 		identical_paths = 
 			(i > 0) &&
@@ -55,6 +82,7 @@ void chip_enumerate(struct chip *chip)
 			parent = chip->bus;
 			switch(chip->path[i].path.type) {
 			case DEVICE_PATH_NONE:
+				/* no dynamic device associated */
 				break;
 			case DEVICE_PATH_PCI:
 				bus = chip->path[i].path.u.pci.bus;
@@ -62,7 +90,7 @@ void chip_enumerate(struct chip *chip)
 					device_t dev;
 					int i = 1;
 					dev = chip->dev;
-					while(dev && (i != bus)) {
+					while (dev && (i != bus)) {
 						dev = dev->next;
 						i++;
 					}
@@ -75,18 +103,21 @@ void chip_enumerate(struct chip *chip)
 				dev = alloc_dev(parent, &chip->path[i].path);
 				break;
 			}
-		}
+		} else {
-		else {
 			link += 1;
 		}
+
 		if (dev) {
 			struct chip_resource *res, *res_limit;
-			printk_spew("path (%p) %s %s", dev, dev_path(dev), identical_paths?"identical":"");
+			printk_spew("path (%p) %s %s",
-			printk_spew(" parent: (%p) %s\n",dev->bus->dev,  dev_path(dev->bus->dev));
+				    dev, dev_path(dev),
+				    identical_paths?"identical":"");
+			printk_spew(" parent: (%p) %s\n",
+				    dev->bus->dev,  dev_path(dev->bus->dev));
 			dev->chip = chip;
 			dev->enable = chip->path[i].enable;
 			dev->links = link + 1;
-			for(child = chip->children; child; child = child->next) {
+			for (child = chip->children; child; child = child->next) {
 				if (!child->bus && child->link == i) {
 					child->bus = &dev->link[link];
 				}
@@ -102,21 +133,42 @@ void chip_enumerate(struct chip *chip)
 				}
 			}
 		}
+
 		if (dev && !chip->dev) {
 			chip->dev = dev;
 		}
 	}
-	for(child = chip->children; child; child = child->next) {
+
+	for (child = chip->children; child; child = child->next) {
 		if (!child->bus) {
 			child->bus = &chip->dev->link[0];
 		}
 	}
 }
 
+/**
+ * @brief Enumerate a static device tree.
+ *
+ * A static device chain is a linked list of static device structures which are
+ * on the same branch of the static device tree. This function does not only
+ * enumerate the devices on a single chain, as its name suggest, it also walks
+ * into the subordinary chains. It calls the device specific
+ * chip_control::enumerate() of the device if one exists or calls the generic
+ * chip_enumerate(). 
+ *
+ * This function is only an iterator, the exact definition of 'enumerate'
+ * depends on the implementation of the generic chip_enumerate() and/or device
+ * specific chip_control::enumerate(). 
+ *
+ * @param root static chip structure to start with.
+ *
+ * @see chip_control::enumerate()
+ */
 static void enumerate_static_device_chain(struct chip *root)
 {
 	struct chip *chip;
-	for(chip = root; chip; chip = chip->next) {
+
+	for (chip = root; chip; chip = chip->next) {
 		void (*enumerate)(struct chip *chip);
 		enumerate = chip_enumerate;
 		if (chip->control && chip->control->enumerate) {
@@ -125,13 +177,30 @@ static void enumerate_static_device_chain(struct chip *root)
 		enumerate(chip);
 	}
 
-	for(chip = root; chip; chip = chip->next) {
+	for (chip = root; chip; chip = chip->next) {
 		if (chip->children) {
 			enumerate_static_device_chain(chip->children);
 		}
 	}
 }
 
+/**
+ * @brief Enumerate static devices in the system.
+ *
+ * \note The definition of 'enumerate' is not clear in this context. Does it mean
+ * probe ?
+ *
+ * \note How do we determine the existence of the static devices ? Static
+ * devices are listed in the config file and generated at compile time by config
+ * tool. This function is called at certain point in the early stage of
+ * LinuxBIOS. It uses the chip_enumerate() function to convert the static
+ * structures into dynamic ones. What if the static devices listed in the config
+ * file does actually not exist in the system ? Is there any side effect of
+ * these 'phantom' device structures
+ *
+ * The static device does not necesarry conform to the dynamic device tree in
+ * the system.
+ */
 void enumerate_static_devices(void)
 {
 	enumerate_static_device_chain(&static_root);

src/devices/device.c

@@ -22,24 +22,41 @@
 #include <stdlib.h>
 #include <string.h>
 
-/* Linked list of ALL devices */
+/** Linked list of ALL devices */
 struct device *all_devices = &dev_root;
-/* pointer to the last device */
+/** Pointer to the last device */
 static struct device **last_dev_p = &dev_root.next;
 
-#define DEVICE_MEM_HIGH  0xFEC00000UL /* Reserve 20M for the system */
+/** The upper limit of MEM resource of the devices.
+ * Reserve 20M for the system */
+#define DEVICE_MEM_HIGH 0xFEC00000UL
+/** The lower limit of IO resource of the devices.
+ * Reserve 4k for ISA/Legacy devices */
 #define DEVICE_IO_START 0x1000
 
-/** Allocate a new device structure
+/**
+ * @brief Allocate a new device structure.
+ * 
+ * Allocte a new device structure and attached it to the device tree as a child
+ * of the parent bus.
+ *
+ * @param parent parent bus the newly created device attached to.
+ * @param path path to the device to be created.
+ *
+ * @return pointer to the newly created device structure.
+ *
+ * @see device_path
  */
 device_t alloc_dev(struct bus *parent, struct device_path *path)
 {
 	device_t dev, child;
 	int link;
+
 	/* Find the last child of our parent */
-	for(child = parent->children; child && child->sibling; ) {
+	for (child = parent->children; child && child->sibling; ) {
 		child = child->sibling;
 	}
+
 	dev = malloc(sizeof(*dev));
 	if (dev == 0) {
 		die("DEV: out of memory.\n");
@@ -47,14 +64,14 @@ device_t alloc_dev(struct bus *parent, struct device_path *path)
 	memset(dev, 0, sizeof(*dev));
 	memcpy(&dev->path, path, sizeof(*path));
 
-	/* Append a new device to the global device chain.
+	/* Append a new device to the global device list.
-	 * The chain is used to find devices once everything is set up.
+	 * The list is used to find devices once everything is set up.
 	 */
 	*last_dev_p = dev;
 	last_dev_p = &dev->next;
 
 	/* Initialize the back pointers in the link fields */
-	for(link = 0; link < MAX_LINKS; link++) {
+	for (link = 0; link < MAX_LINKS; link++) {
 		dev->link[link].dev  = dev;
 		dev->link[link].link = link;
 	}
@@ -66,12 +83,15 @@ device_t alloc_dev(struct bus *parent, struct device_path *path)
 	} else {
 		parent->children = dev;
 	}
+
 	/* If we don't have any other information about a device enable it */
 	dev->enable = 1;
+
 	return dev;
 }
 
-/** round a number to an alignment. 
+/**
+ * @brief round a number up to an alignment. 
  * @param val the starting value
  * @param roundup Alignment as a power of two
  * @returns rounded up number
@@ -104,7 +124,7 @@ static void read_resources(struct bus *bus)
 	struct device *curdev;
 
 	/* Walk through all of the devices and find which resources they need. */
-	for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+	for (curdev = bus->children; curdev; curdev = curdev->sibling) {
 		unsigned links;
 		int i;
 		if (curdev->resources > 0) {
@@ -112,20 +132,22 @@ static void read_resources(struct bus *bus)
 		}
 		if (!curdev->ops || !curdev->ops->read_resources) {
 			printk_err("%s missing read_resources\n",
-				dev_path(curdev));
+				   dev_path(curdev));
 			continue;
 		}
 		if (!curdev->enable) {
 			continue;
 		}
+
 		curdev->ops->read_resources(curdev);
+
 		/* Read in subtractive resources behind the current device */
 		links = 0;
-		for(i = 0; i < curdev->resources; i++) {
+		for (i = 0; i < curdev->resources; i++) {
 			struct resource *resource;
 			resource = &curdev->resource[i];
 			if ((resource->flags & IORESOURCE_SUBTRACTIVE) &&
-				(!(links & (1 << resource->index))))
+			    (!(links & (1 << resource->index))))
 			{
 				links |= (1 << resource->index);
 				read_resources(&curdev->link[resource->index]);
@@ -142,8 +164,8 @@ struct pick_largest_state {
 	int seen_last;
 };
 
-static void pick_largest_resource(
+static void pick_largest_resource(struct pick_largest_state *state,
-	struct pick_largest_state *state, struct device *dev, struct resource *resource)
+				  struct device *dev, struct resource *resource)
 {
 	struct resource *last;
 	last = state->last;
@@ -152,32 +174,33 @@ static void pick_largest_resource(
 		state->seen_last = 1;
 		return;
 	}
-	if (last && (
+	if (last &&
-		    (last->align < resource->align) ||
+	    ((last->align < resource->align) ||
-		    ((last->align == resource->align) &&
+	     ((last->align == resource->align) &&
-			    (last->size < resource->size)) ||
+	      (last->size < resource->size)) ||
-		    ((last->align == resource->align) &&
+	     ((last->align == resource->align) &&
-			    (last->size == resource->size) &&
+	      (last->size == resource->size) &&
-			    (!state->seen_last)))) {
+	      (!state->seen_last)))) {
 		return;
 	}
-	if (!state->result || 
+	if (!state->result ||
-		(state->result->align < resource->align) ||
+	    (state->result->align < resource->align) ||
-		((state->result->align == resource->align) &&
+	    ((state->result->align == resource->align) &&
-			(state->result->size < resource->size))) {
+	     (state->result->size < resource->size))) {
 		state->result_dev = dev;
 		state->result = resource;
-	}
+	}    
-		    
 }
 
 static void find_largest_resource(struct pick_largest_state *state, 
-	struct bus *bus, unsigned long type_mask, unsigned long type)
+				  struct bus *bus, unsigned long type_mask,
+				  unsigned long type)
 {
 	struct device *curdev;
-	for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+
+	for (curdev = bus->children; curdev; curdev = curdev->sibling) {
 		int i;
-		for(i = 0; i < curdev->resources; i++) {
+		for (i = 0; i < curdev->resources; i++) {
 			struct resource *resource = &curdev->resource[i];
 			/* If it isn't the right kind of resource ignore it */
 			if ((resource->flags & type_mask) != type) {
@@ -187,7 +210,8 @@ static void find_largest_resource(struct pick_largest_state *state,
 			if (resource->flags & IORESOURCE_SUBTRACTIVE) {
 				struct bus *subbus;
 				subbus = &curdev->link[resource->index];
-				find_largest_resource(state, subbus, type_mask, type);
+				find_largest_resource(state, subbus,
+						      type_mask, type);
 				continue;
 			}
 			/* See if this is the largest resource */
@@ -196,8 +220,10 @@ static void find_largest_resource(struct pick_largest_state *state,
 	}
 }
 
-static struct device *largest_resource(struct bus *bus, struct resource **result_res,
+static struct device *largest_resource(struct bus *bus,
-	unsigned long type_mask, unsigned long type)
+				       struct resource **result_res,
+				       unsigned long type_mask,
+				       unsigned long type)
 {
 	struct pick_largest_state state;
 
@@ -254,12 +280,12 @@ void compute_allocate_resource(
 	min_align = 0;
 	base = bridge->base;
 
-	printk_spew("%s compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d\n", 
+	printk_spew("%s compute_allocate_%s: base: %08lx size: %08lx "
-		dev_path(bus->dev),
+		    "align: %d gran: %d\n", 
-		(bridge->flags & IORESOURCE_IO)? "io":
+		    dev_path(bus->dev),
-		(bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
+		    (bridge->flags & IORESOURCE_IO)? "io":
-		base, bridge->size, bridge->align, bridge->gran);
+		    (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
-
+		    base, bridge->size, bridge->align, bridge->gran);
 
 	/* We want different minimum alignments for different kinds of
 	 * resources.  These minimums are not device type specific
@@ -278,8 +304,9 @@ void compute_allocate_resource(
 	/* Remember I haven't found anything yet. */
 	resource = 0;
 
-	/* Walk through all the devices on the current bus and compute the addresses */
+	/* Walk through all the devices on the current bus and compute the
-	while((dev = largest_resource(bus, &resource, type_mask, type))) {
+	 * addresses */
+	while ((dev = largest_resource(bus, &resource, type_mask, type))) {
 		unsigned long size;
 		/* Do NOT I repeat do not ignore resources which have zero size.
 		 * If they need to be ignored dev->read_resources should not even
@@ -357,6 +384,8 @@ void compute_allocate_resource(
 static void allocate_vga_resource(void)
 {
 #warning "FIXME modify allocate_vga_resource so it is less pci centric!"
+#warning "This function knows to much about PCI stuff, it should be just a ietrator/visitor."
+
 	/* FIXME handle the VGA pallette snooping */
 	struct device *dev, *vga;
 	struct bus *bus;
@@ -422,7 +451,7 @@ void enable_resources(struct device *dev)
 	 */
 	if (!dev->ops || !dev->ops->enable_resources) {
 		printk_err("%s missing enable_resources\n",
-			dev_path(dev));
+			   dev_path(dev));
 		return;
 	}
 	if (!dev->enable) {
@@ -431,58 +460,74 @@ void enable_resources(struct device *dev)
 	dev->ops->enable_resources(dev);
 }
 
-/** Enumerate the resources on the PCI by calling pci_init
+/**
+ * @brief Determine the existence of dynamic devices and construct dynamic
+ * device tree.
+ *
+ * Start for the root device 'dev_root', scan the buses in the system, build
+ * the dynamic device tree according to the result of the probe.
+ *
+ * This function have no idea how to scan and probe the buses and devices at
+ * all. It depends on the bus/device specific scan_bus() method to do it.
+ * The scan_bus() function also have to create the device structure and attach
+ * it to the device tree. 
  */
 void dev_enumerate(void)
 {
 	struct device *root;
 	unsigned subordinate;
-	printk_info("Enumerating buses...");
+
+	printk_info("Enumerating buses...\n");
+
 	root = &dev_root;
 	subordinate = root->ops->scan_bus(root, 0);
+
 	printk_info("done\n");
 }
 
-/** Starting at the root, compute what resources are needed and allocate them. 
+/**
+ * @brief Configure devices on the devices tree.
+ * 
+ * Starting at the root, compute what resources are needed and allocate them. 
  * I/O starts at PCI_IO_START. Since the assignment is hierarchical we
  * set the values into the dev_root struct. 
  */
 void dev_configure(void)
 {
 	struct device *root = &dev_root;
+
 	printk_info("Allocating resources...");
 	printk_debug("\n");
 
-
 	root->ops->read_resources(root);
 
-	/* Make certain the io devices are allocated somewhere
+	/* Make certain the io devices are allocated somewhere safe. */
-	 * safe.
-	 */
 	root->resource[0].base = DEVICE_IO_START;
 	root->resource[0].flags |= IORESOURCE_ASSIGNED;
 	root->resource[0].flags &= ~IORESOURCE_STORED;
-	/* Now reallocate the pci resources memory with the
+
-	 * highest addresses I can manage.
+	/* Now reallocate the pci resources memory with the highest
-	 */
+	 * addresses I can manage.*/
 	root->resource[1].base = 
 		round_down(DEVICE_MEM_HIGH - root->resource[1].size,
-			1UL << root->resource[1].align);
+			   1UL << root->resource[1].align);
 	root->resource[1].flags |= IORESOURCE_ASSIGNED;
 	root->resource[1].flags &= ~IORESOURCE_STORED;
 
-	/* Allocate the VGA I/O resource..
+	/* Allocate the VGA I/O resource.. */
-	 */
 	allocate_vga_resource(); 
 
-	// now just set things into registers ... we hope ...
+	/* now just set things into registers ... we hope ... */
 	root->ops->set_resources(root);
 
 	printk_info("done.\n");
 }
 
-/** Starting at the root, walk the tree and enable all devices/bridges. 
+/**
- * What really happens is computed COMMAND bits get set in register 4
+ * @brief Enable devices on the device tree.
+ *
+ * Starting at the root, walk the tree and enable all devices/bridges by
+ * calling the device's enable_resources() method.
  */
 void dev_enable(void)
 {
@@ -490,22 +535,28 @@ void dev_enable(void)
 
 	/* now enable everything. */
 	enable_resources(&dev_root);
+
 	printk_info("done.\n");
 }
 
-/** Starting at the root, walk the tree and call a driver to
+/**
- *  do device specific setup.
+ * @brief Initialize all devices in the global device list.
+ *
+ * Starting at the first device on the global device link list,
+ * walk the list and call a driver to do device specific setup.
  */
 void dev_initialize(void)
 {
 	struct device *dev;
 
 	printk_info("Initializing devices...\n");
+
 	for (dev = all_devices; dev; dev = dev->next) {
 		if (dev->enable && dev->ops && dev->ops->init) {
 			printk_debug("%s init\n", dev_path(dev));
 			dev->ops->init(dev);
 		}
 	}
+
 	printk_info("Devices initialized\n");
 }

src/devices/device_util.c

@@ -6,15 +6,16 @@
 
 
 /**
- * See if a device structure already exists and if not allocate it
+ * @brief See if a device structure already exists and if not allocate it
+ *
  * @param bus The bus to find the device on
  * @param path The relative path from the bus to the appropriate device
- * @return pointer a device structure for the device on bus at path
+ * @return pointer to a device structure for the device on bus at path
  */
 device_t alloc_find_dev(struct bus *parent, struct device_path *path)
 {
 	device_t child;
-	for(child = parent->children; child; child = child->sibling) {
+	for (child = parent->children; child; child = child->sibling) {
 		if (path_eq(path, &child->path)) {
 			return child;
 		}

src/devices/pci_device.c

@@ -151,7 +151,7 @@ static void pci_read_bases(struct device *dev, unsigned int howmany)
 {
 	unsigned long index;
 
-	for(index = PCI_BASE_ADDRESS_0; (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) {
+	for (index = PCI_BASE_ADDRESS_0; (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) {
 		struct resource *resource;
 		resource = pci_get_resource(dev, index);
 		index += (resource->flags & IORESOURCE_PCI64)?8:4;
@@ -159,7 +159,6 @@ static void pci_read_bases(struct device *dev, unsigned int howmany)
 	compact_resources(dev);
 }
 
-
 static void pci_bridge_read_bases(struct device *dev)
 {
 	struct resource *resource;
@@ -174,7 +173,7 @@ static void pci_bridge_read_bases(struct device *dev)
 	resource->limit = 0xffffUL;
 	resource->flags |= IORESOURCE_IO | IORESOURCE_PCI_BRIDGE;
 	compute_allocate_resource(&dev->link[0], resource,
-		IORESOURCE_IO, IORESOURCE_IO);
+				  IORESOURCE_IO, IORESOURCE_IO);
 
 	/* Initiliaze the prefetchable memory constraints on the current bus */
 	resource = get_resource(dev, PCI_PREF_MEMORY_BASE);
@@ -185,8 +184,8 @@ static void pci_bridge_read_bases(struct device *dev)
 	resource->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_PCI_BRIDGE;
 	resource->index = PCI_PREF_MEMORY_BASE;
 	compute_allocate_resource(&dev->link[0], resource,
-		IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+				  IORESOURCE_MEM | IORESOURCE_PREFETCH, 
-		IORESOURCE_MEM | IORESOURCE_PREFETCH);
+				  IORESOURCE_MEM | IORESOURCE_PREFETCH);
 
 	/* Initialize the memory resources on the current bus */
 	resource = get_resource(dev, PCI_MEMORY_BASE);
@@ -196,17 +195,18 @@ static void pci_bridge_read_bases(struct device *dev)
 	resource->limit = 0xffffffffUL;
 	resource->flags = IORESOURCE_MEM | IORESOURCE_PCI_BRIDGE;
 	compute_allocate_resource(&dev->link[0], resource,
-		IORESOURCE_MEM | IORESOURCE_PREFETCH,
+				  IORESOURCE_MEM | IORESOURCE_PREFETCH,
-		IORESOURCE_MEM);
+				  IORESOURCE_MEM);
 
 	compact_resources(dev);
 }
 
-
 void pci_dev_read_resources(struct device *dev)
 {
 	uint32_t addr;
+
 	pci_read_bases(dev, 6);
+
 	addr = pci_read_config32(dev, PCI_ROM_ADDRESS);
 	dev->rom_address = (addr == 0xffffffff)? 0 : addr;
 }
@@ -214,14 +214,29 @@ void pci_dev_read_resources(struct device *dev)
 void pci_bus_read_resources(struct device *dev)
 {
 	uint32_t addr;
+
 	pci_bridge_read_bases(dev);
 	pci_read_bases(dev, 2);
 	
 	addr = pci_read_config32(dev, PCI_ROM_ADDRESS1);
 	dev->rom_address = (addr == 0xffffffff)? 0 : addr;
-
 }
 
+/**
+ * @brief round a number up to an alignment. 
+ * @param val the starting value
+ * @param roundup Alignment as a power of two
+ * @returns rounded up number
+ */
+static unsigned long round(unsigned long val, unsigned long roundup)
+{
+	/* ROUNDUP MUST BE A POWER OF TWO. */
+	unsigned long inverse;
+	inverse = ~(roundup - 1);
+	val += (roundup - 1);
+	val &= inverse;
+	return val;
+}
 
 static void pci_set_resource(struct device *dev, struct resource *resource)
 {
@@ -230,11 +245,10 @@ static void pci_set_resource(struct device *dev, struct resource *resource)
 	unsigned long gran;
 
 	/* Make certain the resource has actually been set */
+
 	if (!(resource->flags & IORESOURCE_ASSIGNED)) {
-#if 1
 		printk_err("ERROR: %s %02x not allocated\n",
-			dev_path(dev), resource->index);
+			   dev_path(dev), resource->index);
-#endif
 		return;
 	}
 
@@ -256,8 +270,10 @@ static void pci_set_resource(struct device *dev, struct resource *resource)
 	if (resource->flags & IORESOURCE_PCI_BRIDGE) {
 		dev->command |= PCI_COMMAND_MASTER;
 	}
+
 	/* Get the base address */
 	base = resource->base;
+
 	/* Get the resource granularity */
 	gran = 1UL << resource->gran;
 
@@ -268,15 +284,13 @@ static void pci_set_resource(struct device *dev, struct resource *resource)
 	 */
 	
 	/* Get the limit (rounded up) */
-	limit = base + ((resource->size + gran - 1UL) & ~(gran - 1UL)) -1UL;
+	limit = base + round(resource->size, gran) - 1UL;
 	
 	/* Now store the resource */
 	resource->flags |= IORESOURCE_STORED;
 	if (!(resource->flags & IORESOURCE_PCI_BRIDGE)) {
-		/*
+		/* some chipsets allow us to set/clear the IO bit. 
-		 * some chipsets allow us to set/clear the IO bit. 
+		 * (e.g. VIA 82c686a.) So set it to be safe) */
-		 * (e.g. VIA 82c686a.) So set it to be safe)
-		 */
 		limit = base + resource->size -1;
 		if (resource->flags & IORESOURCE_IO) {
 			base |= PCI_BASE_ADDRESS_SPACE_IO;
@@ -286,58 +300,50 @@ static void pci_set_resource(struct device *dev, struct resource *resource)
 			/* FIXME handle real 64bit base addresses */
 			pci_write_config32(dev, resource->index + 4, 0);
 		}
-	}
+	} else if (resource->index == PCI_IO_BASE) {
-	else if (resource->index == PCI_IO_BASE) {
 		/* set the IO ranges
 		 * WARNING: we don't really do 32-bit addressing for IO yet! 
 		 */
 		compute_allocate_resource(&dev->link[0], resource, 
-			IORESOURCE_IO, IORESOURCE_IO);
+					  IORESOURCE_IO, IORESOURCE_IO);
 		pci_write_config8(dev, PCI_IO_BASE,  base >> 8);
 		pci_write_config8(dev, PCI_IO_LIMIT, limit >> 8);
 		pci_write_config16(dev, PCI_IO_BASE_UPPER16, 0);
 		pci_write_config16(dev, PCI_IO_LIMIT_UPPER16, 0);
-	}
+	} else if (resource->index == PCI_MEMORY_BASE) {
-	else if (resource->index == PCI_MEMORY_BASE) {
+		/* set the memory range */
-		/* set the memory range
-		 */
 		compute_allocate_resource(&dev->link[0], resource,
-			IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+					  IORESOURCE_MEM | IORESOURCE_PREFETCH, 
-			IORESOURCE_MEM);
+					  IORESOURCE_MEM);
 		pci_write_config16(dev, PCI_MEMORY_BASE, base >> 16);
 		pci_write_config16(dev, PCI_MEMORY_LIMIT, limit >> 16);
-	}
+	} else if (resource->index == PCI_PREF_MEMORY_BASE) {
-	else if (resource->index == PCI_PREF_MEMORY_BASE) {
 		/* set the prefetchable memory range
-		 * WARNING: we don't really do 64-bit addressing for prefetchable memory yet!
+		 * WARNING: we don't really do 64-bit addressing for
-		 */
+		 * prefetchable memory yet! */
 		compute_allocate_resource(&dev->link[0], resource,
-			IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+					  IORESOURCE_MEM | IORESOURCE_PREFETCH, 
-			IORESOURCE_MEM | IORESOURCE_PREFETCH);
+					  IORESOURCE_MEM | IORESOURCE_PREFETCH);
 		pci_write_config16(dev, PCI_PREF_MEMORY_BASE,  base >> 16);
 		pci_write_config16(dev, PCI_PREF_MEMORY_LIMIT, limit >> 16);
 		pci_write_config32(dev, PCI_PREF_BASE_UPPER32, 0);
 		pci_write_config32(dev, PCI_PREF_LIMIT_UPPER32, 0);
-	}
+	} else {
-	else {
 		/* Don't let me think I stored the resource */
 		resource->flags &= ~IORESOURCE_STORED;
 		printk_err("ERROR: invalid resource->index %x\n",
-			resource->index);
+			   resource->index);
 	}
+
 	buf[0] = '\0';
 	if (resource->flags & IORESOURCE_PCI_BRIDGE) {
 		sprintf(buf, "bus %d ", dev->link[0].secondary);
 	}
-	
+	printk_debug("%s %02x <- [0x%08lx - 0x%08lx] %s%s\n",
-	printk_debug(
+		     dev_path(dev), resource->index, resource->base,
-		"%s %02x <- [0x%08lx - 0x%08lx] %s%s\n",
+		     limit, buf,
-		dev_path(dev),
+		     (resource->flags & IORESOURCE_IO)? "io":
-		resource->index, 
+		     (resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem");
-		resource->base, limit,
-		buf,
-		(resource->flags & IORESOURCE_IO)? "io":
-		(resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem");
 	return;
 }
 
@@ -348,11 +354,11 @@ void pci_dev_set_resources(struct device *dev)
 	uint8_t line;
 
 	last = &dev->resource[dev->resources];
-
+	for (resource = &dev->resource[0]; resource < last; resource++) {
-	for(resource = &dev->resource[0]; resource < last; resource++) {
 		pci_set_resource(dev, resource);
 	}
-	for(link = 0; link < dev->links; link++) {
+
+	for (link = 0; link < dev->links; link++) {
 		struct bus *bus;
 		bus = &dev->link[link];
 		if (bus->children) {
@@ -401,43 +407,55 @@ void pci_bus_enable_resources(struct device *dev)
 	pci_dev_enable_resources(dev);
 }
 
+/** Default device operation for PCI devices */
 struct device_operations default_pci_ops_dev = {
 	.read_resources   = pci_dev_read_resources,
 	.set_resources    = pci_dev_set_resources,
 	.enable_resources = pci_dev_enable_resources,
-	.init = 0,
+	.init		  = 0,
-	.scan_bus = 0,
+	.scan_bus	  = 0,
 };
+
+/** Default device operations for PCI bridges */
 struct device_operations default_pci_ops_bus = {
 	.read_resources   = pci_bus_read_resources,
 	.set_resources    = pci_dev_set_resources,
 	.enable_resources = pci_bus_enable_resources,
-	.init = 0,
+	.init		  = 0,
-	.scan_bus = pci_scan_bridge,
+	.scan_bus	  = pci_scan_bridge,
 };
+
+/**
+ * @brief Set up PCI device operation
+ *
+ *
+ * @param dev 
+ *
+ * @see pci_drivers
+ */
 static void set_pci_ops(struct device *dev)
 {
 	struct pci_driver *driver;
+
 	if (dev->ops) {
 		return;
 	}
+
 	/* Look through the list of setup drivers and find one for
-	 * this pci device 
+	 * this pci device */
-	 */
+	for (driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) {
-	for(driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) {
 		if ((driver->vendor == dev->vendor) &&
-			(driver->device == dev->device)) {
+		    (driver->device == dev->device)) {
 			dev->ops = driver->ops;
-#if 1
+
-			printk_debug("%s [%04x/%04x] %sops\n", 
+			printk_debug("%s [%04x/%04x] %sops\n", dev_path(dev),
-				dev_path(dev),
+				     driver->vendor, driver->device,
-				driver->vendor, driver->device,
+				     (driver->ops->scan_bus?"bus ":""));
-				(driver->ops->scan_bus?"bus ":"")
+
-				);
-#endif
 			return;
 		}
 	}
+
 	/* If I don't have a specific driver use the default operations */
 	switch(dev->hdr_type & 0x7f) {	/* header type */
 	case PCI_HEADER_TYPE_NORMAL:	/* standard header */
@@ -454,27 +472,35 @@ static void set_pci_ops(struct device *dev)
 	bad:
 		if (dev->enable) {
 			printk_err("%s [%04x/%04x/%06x] has unknown header "
-				"type %02x, ignoring.\n",
+				   "type %02x, ignoring.\n",
-				dev_path(dev),
+				   dev_path(dev),
-				dev->vendor, dev->device, 
+				   dev->vendor, dev->device, 
-				dev->class >> 8, dev->hdr_type);
+				   dev->class >> 8, dev->hdr_type);
 		}
 	}
 	return;
 }
 
 /**
- * Given a bus and a devfn number, find the device structure
+ * @brief Find a specific device structure on a list of device structures
- * @param bus The bus structure
+ *
+ * Given a linked list of PCI device structures and a devfn number, find the
+ * device structure correspond to the devfn.
+ *
+ * @param list the device structure list
  * @param devfn a device/function number
- * @return pointer to the device structure
+ *
+ * @return pointer to the device structure found
  */
-static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn)
+static struct device *pci_scan_get_dev(struct device **list,
+				       unsigned int devfn)
 {
 	struct device *dev = 0;
-	for(; *list; list = &(*list)->sibling) {
+
+	for (; *list; list = &(*list)->sibling) {
 		if ((*list)->path.type != DEVICE_PATH_PCI) {
-			printk_err("child %s not a pci device\n", dev_path(*list));
+			printk_err("child %s not a pci device\n",
+				   dev_path(*list));
 			continue;
 		}
 		if ((*list)->path.u.pci.devfn == devfn) {
@@ -485,10 +511,13 @@ static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn)
 			break;
 		}
 	}
+
+	/* FIXME: why are we doing this ? Isn't there some order between the
+	 * structures before ? */
 	if (dev) {
 		device_t child;
 		/* Find the last child of our parent */
-		for(child = dev->bus->children; child && child->sibling; ) {
+		for (child = dev->bus->children; child && child->sibling; ) {
 			child = child->sibling;
 		}
 		/* Place the device on the list of children of it's parent. */
@@ -502,16 +531,24 @@ static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn)
 	return dev;
 }
 
-/** Scan the pci bus devices and bridges.
+/**
+ * @brief Scan a PCI bus
+ *
+ * Determine the existence of devices and bridges on a PCI bus. If there are
+ * bridges on the bus, recursively scan the buses behind the bridges.
+ *
+ * This function is the default scan_bus() method for the root device
+ * 'dev_root'.
+ *
  * @param bus pointer to the bus structure
  * @param min_devfn minimum devfn to look at in the scan usually 0x00
  * @param max_devfn maximum devfn to look at in the scan usually 0xff
  * @param max current bus number
+ *
  * @return The maximum bus number found, after scanning all subordinate busses
  */
-unsigned int pci_scan_bus(struct bus *bus,
+unsigned int pci_scan_bus(struct bus *bus, unsigned min_devfn,
-	unsigned min_devfn, unsigned max_devfn,
+			  unsigned max_devfn, unsigned int max)
-	unsigned int max)
 {
 	unsigned int devfn;
 	device_t dev;
@@ -524,42 +561,50 @@ unsigned int pci_scan_bus(struct bus *bus,
 	bus->children = 0;
 
 	post_code(0x24);
-	
 
-	/* probe all devices on this bus with some optimization for non-existance and 
+	/* probe all devices on this bus with some optimization for
-	   single funcion devices */
+	 * non-existence and single funcion devices */
 	for (devfn = min_devfn; devfn <= max_devfn; devfn++) {
 		uint32_t id, class;
 		uint8_t hdr_type;
 
-		/* First thing setup the device structure */
+		/* device structures for PCI devices associated with static
+		 * devices are already created during the static device
+		 * enumeration, find out if it is the case for this devfn */
 		dev = pci_scan_get_dev(&old_devices, devfn);
-	
+
-		/* Detect if a device is present */
 		if (!dev) {
+			/* it's not associated with a static device, detect if
+			 * this device is present */
 			struct device dummy;
 			dummy.bus              = bus;
 			dummy.path.type        = DEVICE_PATH_PCI;
 			dummy.path.u.pci.devfn = devfn;
 			id = pci_read_config32(&dummy, PCI_VENDOR_ID);
 			/* some broken boards return 0 if a slot is empty: */
-			if (	(id == 0xffffffff) || (id == 0x00000000) || 
+			if ((id == 0xffffffff) || (id == 0x00000000) || 
-				(id == 0x0000ffff) || (id == 0xffff0000))
+			    (id == 0x0000ffff) || (id == 0xffff0000)) {
-			{
+				printk_spew("PCI: devfn 0x%x, bad id 0x%x\n",
-				printk_spew("PCI: devfn 0x%x, bad id 0x%x\n", devfn, id);
+					    devfn, id);
 				if (PCI_FUNC(devfn) == 0x00) {
-					/* if this is a function 0 device and it is not present,
+					/* if this is a function 0 device and
-					   skip to next device */
+					 * it is not present, skip to next
+					 * device */
 					devfn += 0x07;
 				}
-				/* multi function device, skip to next function */
+				/* this function in a multi function device is
+				 * not present, skip to next function */
 				continue;
 			}
 			dev = alloc_dev(bus, &dummy.path);
-		}
+		} else {
-		else {
+			/* Run the magic enable/disable sequence for the
-			/* Run the magic enable sequence for the device */
+			 * device */
-			if (dev->chip && dev->chip->control && dev->chip->control->enable_dev) {
+			/* FIXME: What happen if this PCI device listed as
+			 * static device but does not exist ? This calls
+			 * some arbitray code without any justification */
+			if (dev->chip && dev->chip->control &&
+			    dev->chip->control->enable_dev) {
 				int enable  = dev->enable;
 				dev->enable = 1;
 				dev->chip->control->enable_dev(dev);
@@ -580,14 +625,15 @@ unsigned int pci_scan_bus(struct bus *bus,
 		dev->class = class >> 8;
 
 		/* Look at the vendor and device id, or at least the 
-		 * header type and class and figure out which set of configuration
+		 * header type and class and figure out which set of
-		 * methods to use.  Unless we already have some pci ops.
+		 * configuration methods to use.  Unless we already
+		 * have some pci ops.
 		 */
 		set_pci_ops(dev);
 		/* Error if we don't have some pci operations for it */
 		if (!dev->ops) {
 			printk_err("%s No device operations\n",
-				dev_path(dev));
+				   dev_path(dev));
 			continue;
 		}
 
@@ -600,24 +646,28 @@ unsigned int pci_scan_bus(struct bus *bus,
 		}
 
 		printk_debug("%s [%04x/%04x] %s\n", 
-			dev_path(dev),
+			     dev_path(dev),
-			dev->vendor, dev->device, 
+			     dev->vendor, dev->device, 
-			dev->enable?"enabled": "disabled");
+			     dev->enable?"enabled": "disabled");
 
 		if (PCI_FUNC(devfn) == 0x00 && (hdr_type & 0x80) != 0x80) {
-			/* if this is not a multi function device, don't waste time probe
+			/* if this is not a multi function device, don't
-			   another function. Skip to next device. */
+			 * waste time probe another function.
+			 * Skip to next device. */
 			devfn += 0x07;
 		}
 	}
 	post_code(0x25);
 
-	for(child = bus->children; child; child = child->sibling) {
+	/* if the child provides scan_bus(), for example a bridge, scan the
+	 * bus behind that child */
+	for (child = bus->children; child; child = child->sibling) {
 		if (!child->ops->scan_bus) {
 			continue;
 		}
 		max = child->ops->scan_bus(child, max);
 	}
+
 	/*
 	 * We've scanned the bus and so we know all about what's on
 	 * the other side of any bridges that may be on this bus plus
@@ -630,8 +680,17 @@ unsigned int pci_scan_bus(struct bus *bus,
 	return max;
 }
 
-/** Scan the bus, first for bridges and next for devices. 
+/**
- * @param pci_bus pointer to the bus structure
+ * @brief Scan a PCI bridge and the buses behind the bridge.
+ *
+ * Determine the existence of buses behind the bridge. Set up the bridge
+ * according to the result of the scan.
+ *
+ * This function is the default scan_bus() method for PCI bridge devices.
+ *
+ * @param dev pointer to the bridge device
+ * @param max the highest bus number assgined up to now
+ *
  * @return The maximum bus number found, after scanning all subordinate busses
  */
 unsigned int pci_scan_bridge(struct device *dev, unsigned int max)
@@ -645,47 +704,44 @@ unsigned int pci_scan_bridge(struct device *dev, unsigned int max)
 
 	/* Set up the primary, secondary and subordinate bus numbers. We have
 	 * no idea how many buses are behind this bridge yet, so we set the
-	 * subordinate bus number to 0xff for the moment 
+	 * subordinate bus number to 0xff for the moment. */
-	 */
 	bus->secondary = ++max;
 	bus->subordinate = 0xff;
-	
+
 	/* Clear all status bits and turn off memory, I/O and master enables. */
 	cr = pci_read_config16(dev, PCI_COMMAND);
 	pci_write_config16(dev, PCI_COMMAND, 0x0000);
 	pci_write_config16(dev, PCI_STATUS, 0xffff);
 
-	/*
+	/* Read the existing primary/secondary/subordinate bus
-	 * Read the existing primary/secondary/subordinate bus
+	 * number configuration. */
-	 * number configuration.
-	 */
 	buses = pci_read_config32(dev, PCI_PRIMARY_BUS);
 
 	/* Configure the bus numbers for this bridge: the configuration
 	 * transactions will not be propagated by the bridge if it is not
-	 * correctly configured 
+	 * correctly configured */
-	 */
 	buses &= 0xff000000;
 	buses |= (((unsigned int) (dev->bus->secondary) << 0) |
-		((unsigned int) (bus->secondary) << 8) |
+		  ((unsigned int) (bus->secondary) << 8) |
-		((unsigned int) (bus->subordinate) << 16));
+		  ((unsigned int) (bus->subordinate) << 16));
 	pci_write_config32(dev, PCI_PRIMARY_BUS, buses);
 	
-	/* Now we can scan all subordinate buses i.e. the bus hehind the bridge */
+	/* Now we can scan all subordinate buses i.e. the buses behind the
+	 * bridge */
 	max = pci_scan_bus(bus, 0x00, 0xff, max);
 	
 	/* We know the number of buses behind this bridge. Set the subordinate
-	 *  bus number to its real value 
+	 * bus number to its real value */
-	 */
 	bus->subordinate = max;
 	buses = (buses & 0xff00ffff) |
 		((unsigned int) (bus->subordinate) << 16);
 	pci_write_config32(dev, PCI_PRIMARY_BUS, buses);
 	pci_write_config16(dev, PCI_COMMAND, cr);
-		
+
 	printk_spew("%s returns max %d\n", __FUNCTION__, max);
 	return max;
 }
+
 /*
     Tell the EISA int controller this int must be level triggered
     THIS IS A KLUDGE -- sorry, this needs to get cleaned up.

src/devices/root_device.c

@@ -21,9 +21,9 @@ void root_dev_read_resources(device_t root)
 	root->resource[res].flags = IORESOURCE_IO;
 	root->resource[res].index = 0;
 	printk_spew("%s . link %p, resource %p\n", __FUNCTION__, 
-					&root->link[0], &root->resource[res]);
+		    &root->link[0], &root->resource[res]);
 	compute_allocate_resource(&root->link[0], &root->resource[res], 
-		IORESOURCE_IO, IORESOURCE_IO);
+				  IORESOURCE_IO, IORESOURCE_IO);
 	res++;
 
 	/* Initialize the system wide memory resources constraints */
@@ -35,9 +35,9 @@ void root_dev_read_resources(device_t root)
 	root->resource[res].flags = IORESOURCE_MEM;
 	root->resource[res].index = 1;
 	printk_spew("%s . link %p, resource %p\n", __FUNCTION__, 
-				&root->link[0], &root->resource[res]);
+		    &root->link[0], &root->resource[res]);
 	compute_allocate_resource(&root->link[0], &root->resource[res], 
-		IORESOURCE_MEM, IORESOURCE_MEM);
+				  IORESOURCE_MEM, IORESOURCE_MEM);
 	res++;
 
 	root->resources = res;
@@ -51,12 +51,12 @@ void root_dev_read_resources(device_t root)
  */
 void root_dev_set_resources(device_t root)
 {
-	struct bus *bus;
+	struct bus *bus = &root->link[0];
-	bus = &root->link[0];
+
-	compute_allocate_resource(bus,
+	compute_allocate_resource(bus, &root->resource[0],
-		&root->resource[0], IORESOURCE_IO, IORESOURCE_IO);
+				  IORESOURCE_IO, IORESOURCE_IO);
-	compute_allocate_resource(bus, 
+	compute_allocate_resource(bus, &root->resource[1],
-		&root->resource[1], IORESOURCE_MEM, IORESOURCE_MEM);
+				  IORESOURCE_MEM, IORESOURCE_MEM);
 	assign_resources(bus);
 }
 
@@ -71,18 +71,18 @@ unsigned int walk_static_devices(device_t bus, unsigned int max)
 {
 	device_t child;
 	unsigned link;
-	for(link = 0; link < bus->links; link++) {
+
-		for(child = bus->link[link].children; child; child = child->sibling) {
+	for (link = 0; link < bus->links; link++) {
+		for (child = bus->link[link].children; child; child = child->sibling) {
 			if (child->ops && child->ops->enable) {
 				child->ops->enable(child);
 			}
-			printk_debug("%s %s\n",
+			printk_debug("%s %s\n", dev_path(child),
-				dev_path(child),
+				     child->enable?"enabled": "disabled");
-				child->enable?"enabled": "disabled");
 		}
 	}
-	for(link = 0; link < bus->links; link++) {
+	for (link = 0; link < bus->links; link++) {
-		for(child = bus->link[link].children; child; child = child->sibling) {
+		for (child = bus->link[link].children; child; child = child->sibling) {
 			if (!child->ops || !child->ops->scan_bus)
 				continue;
 			printk_debug("%s scanning...\n", dev_path(child));
@@ -95,9 +95,9 @@ unsigned int walk_static_devices(device_t bus, unsigned int max)
 void enable_childrens_resources(device_t dev)
 {
 	unsigned link;
-	for(link = 0; link < dev->links; link++) {
+	for (link = 0; link < dev->links; link++) {
 		device_t child;
-		for(child = dev->link[link].children; child; child = child->sibling) {
+		for (child = dev->link[link].children; child; child = child->sibling) {
 			enable_resources(child);
 		}
 	}

src/include/device/device.h

@@ -46,6 +46,7 @@ struct device {
 	unsigned short	device;
 	unsigned int	class;		/* 3 bytes: (base,sub,prog-if) */
 	unsigned int	hdr_type;	/* PCI header type */
+	/* @todo rename this to 'enabled' */
 	unsigned int    enable : 1;	/* set if we should enable the device */
 
 	uint8_t command;

src/include/device/pci.h

@@ -28,7 +28,9 @@ struct pci_driver {
 };
 
 #define __pci_driver __attribute__ ((unused,__section__(".rodata.pci_driver")))
+/** start of compile time generated pci driver array */
 extern struct pci_driver pci_drivers[];
+/** end of compile time generated pci driver array */
 extern struct pci_driver epci_drivers[];
 
 

src/mainboard/tyan/s2885/Config.lb

@@ -6,17 +6,19 @@ uses LB_CKS_RANGE_END
 uses LB_CKS_LOC
 uses MAINBOARD
 uses ARCH
+
 #
 #
 ###
 ### Set all of the defaults for an x86 architecture
 ###
+
 #
 #
 ###
 ### Build the objects we have code for in this directory.
 ###
-##object mainboard.o
+
 config chip.h
 register "fixup_scsi" = "1"
 register "fixup_vga" = "1"
@@ -38,9 +40,10 @@ driver mainboard.o
 object reset.o
 if HAVE_MP_TABLE object mptable.o end
 if HAVE_PIRQ_TABLE object irq_tables.o end
+
 #
 arch i386 end
-#cpu k8 end
+
 #
 ###
 ### Build our 16 bit and 32 bit linuxBIOS entry code
@@ -50,6 +53,7 @@ mainboardinit cpu/i386/entry32.inc
 mainboardinit cpu/i386/bist32.inc
 ldscript /cpu/i386/entry16.lds
 ldscript /cpu/i386/entry32.lds
+
 #
 ###
 ### Build our reset vector (This is where linuxBIOS is entered)
@@ -120,24 +124,30 @@ end
 
 makerule ./failover.inc
 	depends "./romcc ./failover.E"
-	action "./romcc -O -o failover.inc --label-prefix=failover ./failover.E"end
+	action "./romcc -O -o failover.inc --label-prefix=failover ./failover.E"
+end
 
 makerule ./auto.E 
         depends "$(MAINBOARD)/auto.c option_table.h"
         action  "$(CPP) -I$(TOP)/src -I. $(ROMCCPPFLAGS) $(CPPFLAGS) $(MAINBOARD)/auto.c > ./auto.E"
 end
+
 makerule ./auto.inc 
 	depends "./romcc ./auto.E"
 	action "./romcc -O -mcpu=k8 -o auto.inc --label-prefix=auto ./auto.E" 
 #	action	"./romcc -mcpu=k8  -O ./auto.E > auto.inc"
 end
+
 mainboardinit cpu/k8/enable_mmx_sse.inc
 mainboardinit ./auto.inc
 mainboardinit cpu/k8/disable_mmx_sse.inc
+
 #
 ###
 ### Include the secondary Configuration files 
 ###
+dir /pc80
+
 northbridge amd/amdk8 "mc0"
         pci 0:18.0
         pci 0:18.0
@@ -203,7 +213,7 @@ northbridge amd/amdk8 "mc1"
         pci 0:19.2
         pci 0:19.3
 end
-  
+
 dir /pc80
 #dir /bioscall
 

src/mainboard/via/epia/Config.lb

@@ -78,7 +78,8 @@ default HEAP_SIZE=0x4000
 ##
 ## Only use the option table in a normal image
 ##
-default USE_OPTION_TABLE = !USE_FALLBACK_IMAGE
+#default USE_OPTION_TABLE = !USE_FALLBACK_IMAGE
+default USE_OPTION_TABLE = 0
 
 ##
 ## Compute the location and size of where this firmware image

src/mainboard/via/epia/auto.c

@@ -1,8 +1,5 @@
 #define ASSEMBLY 1
 
-//#define MAXIMUM_CONSOLE_LOGLEVEL 6
-//#define DEFAULT_CONSOLE_LOGLEVEL 6
-
 #include <stdint.h>
 #include <device/pci_def.h>
 #include <cpu/p6/apic.h>
@@ -15,6 +12,7 @@
 #include "ram/ramtest.c"
 #include "northbridge/via/vt8601/raminit.h"
 #include "cpu/p6/earlymtrr.c"
+
 /*
  */
 void udelay(int usecs) 

src/northbridge/amd/amdk8/early_ht.c

@@ -16,8 +16,8 @@ static int enumerate_ht_chain(void)
 		id = pci_read_config32(PCI_DEV(0,0,0), PCI_VENDOR_ID);
 		/* If the chain is enumerated quit */
 		if (((id & 0xffff) == 0x0000) || ((id & 0xffff) == 0xffff) ||
-			(((id >> 16) & 0xffff) == 0xffff) ||
+		    (((id >> 16) & 0xffff) == 0xffff) ||
-			(((id >> 16) & 0xffff) == 0x0000)) {
+		    (((id >> 16) & 0xffff) == 0x0000)) {
 			break;
 		}
 		hdr_type = pci_read_config8(PCI_DEV(0,0,0), PCI_HEADER_TYPE);
@@ -25,7 +25,7 @@ static int enumerate_ht_chain(void)
 		hdr_type &= 0x7f;
 
 		if ((hdr_type == PCI_HEADER_TYPE_NORMAL) ||
-			(hdr_type == PCI_HEADER_TYPE_BRIDGE)) {
+		    (hdr_type == PCI_HEADER_TYPE_BRIDGE)) {
 			pos = pci_read_config8(PCI_DEV(0,0,0), PCI_CAPABILITY_LIST);
 		}
 		while(pos != 0) {

src/northbridge/amd/amdk8/northbridge.c

@@ -42,7 +42,7 @@ struct mem_range *sizeram(void)
 	printk_debug("mmio_base: %dKB\n", mmio_basek);
 #endif
 
-	for(idx = i = 0; i < 8; i++) {
+	for (idx = i = 0; i < 8; i++) {
 		uint32_t base, limit;
 		unsigned basek, limitk, sizek;
 		base  = pci_read_config32(dev, 0x40 + (i<<3));
@@ -54,18 +54,18 @@ struct mem_range *sizeram(void)
 		limitk = ((limit + 0x00010000) & 0xffff0000) >> 2;
 		sizek = limitk - basek;
 		if ((idx > 0) &&
-			((mem[idx -1].basek + mem[idx - 1].sizek) == basek)) {
+		    ((mem[idx - 1].basek + mem[idx - 1].sizek) == basek)) {
 			mem[idx -1].sizek += sizek;
-		}
+		} else {
-		else {
 			mem[idx].basek = basek;
 			mem[idx].sizek = sizek;
 			idx++;
 		}
 	
 		/* see if we need a hole from 0xa0000 to 0xbffff */
-		if((mem[idx-1].basek < ((8*64)+(8*16))) && 
+		if ((mem[idx-1].basek < ((8*64)+(8*16))) /* 640 */ && 
-		   (mem[idx-1].sizek > ((8*64)+(16*16)))) {
+		    (mem[idx-1].sizek > ((8*64)+(16*16))) /* 768 */ ) {
+#warning "FIXME: this left 0xA0000 to 0xBFFFF undefined"
 			mem[idx].basek = (8*64)+(16*16);
 			mem[idx].sizek = mem[idx-1].sizek - ((8*64)+(16*16));
 			mem[idx-1].sizek = ((8*64)+(8*16)) - mem[idx-1].basek;
@@ -74,7 +74,7 @@ struct mem_range *sizeram(void)
 		
 		/* See if I need to split the region to accomodate pci memory space */
 		if ((mem[idx - 1].basek <= mmio_basek) &&
-			((mem[idx - 1].basek + mem[idx - 1].sizek) >  mmio_basek)) {
+		    ((mem[idx - 1].basek + mem[idx - 1].sizek) >  mmio_basek)) {
 			if (mem[idx - 1].basek < mmio_basek) {
 				unsigned pre_sizek;
 				pre_sizek = mmio_basek - mem[idx - 1].basek;
@@ -92,10 +92,10 @@ struct mem_range *sizeram(void)
 			}
 		}
 	}
-#if 0
+#if 1
-	for(i = 0; i < idx; i++) {
+	for (i = 0; i < idx; i++) {
 		printk_debug("mem[%d].basek = %08x mem[%d].sizek = %08x\n",
-			i, mem[i].basek, i, mem[i].sizek);
+			     i, mem[i].basek, i, mem[i].sizek);
 	}
 #endif
 	while(idx < sizeof(mem)/sizeof(mem[0])) {
@@ -514,6 +514,40 @@ static void mcf0_control_init(struct device *dev)
 	printk_debug("done.\n");
 }
 
+
+static void amdk8_enable_resources(struct device *dev)
+{
+	uint16_t ctrl;
+	unsigned link;
+	unsigned int vgalink = -1;
+
+	ctrl = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
+	ctrl |= dev->link[0].bridge_ctrl;
+	printk_debug("%s bridge ctrl <- %04x\n", dev_path(dev), ctrl);
+	printk_err("%s bridge ctrl <- %04x\n", dev_path(dev), ctrl);
+	pci_write_config16(dev, PCI_BRIDGE_CONTROL, ctrl);
+
+#if 0
+	/* let's see what link VGA is on */
+	for(link = 0; link < dev->links; link++) {
+		device_t child;
+		printk_err("Kid %d of k8: bridge ctrl says: 0x%x\n",
+			   link, dev->link[link].bridge_ctrl);
+		if (dev->link[link].bridge_ctrl & PCI_BRIDGE_CTL_VGA)
+			vgalink = link;
+	}
+
+	if (vgalink != 1) {
+		/* now find the IOPAIR that goes to vgalink and set the  vga enable in the base part (0x30) */
+		/* now allocate an MMIOPAIR and point it to the CPU0, LINK=vgalink */
+		/* now set IORR1 so it has a hole for the 0xa0000-0xcffff region */
+	}
+#endif
+
+	pci_dev_enable_resources(dev);
+	//enable_childrens_resources(dev);
+}
+
 static struct device_operations northbridge_operations = {
 	.read_resources   = amdk8_read_resources,
 	.set_resources    = amdk8_set_resources,

src/northbridge/amd/amdk8/raminit.c

@@ -5,10 +5,12 @@
 #if (CONFIG_LB_MEM_TOPK & (CONFIG_LB_MEM_TOPK -1)) != 0
 # error "CONFIG_LB_MEM_TOPK must be a power of 2"
 #endif
+
 static void setup_resource_map(const unsigned int *register_values, int max)
 {
 	int i;
 	print_debug("setting up resource map....");
+
 #if 0
 	print_debug("\r\n");
 #endif

src/southbridge/amd/amd8111/amd8111.c

@@ -15,7 +15,7 @@ void amd8111_enable(device_t dev)
 	/* See if we are on the behind the amd8111 pci bridge */
 	bus_dev = dev->bus->dev;
 	if ((bus_dev->vendor == PCI_VENDOR_ID_AMD) && 
-		(bus_dev->device == PCI_DEVICE_ID_AMD_8111_PCI)) {
+	    (bus_dev->device == PCI_DEVICE_ID_AMD_8111_PCI)) {
 		unsigned devfn;
 		devfn = bus_dev->path.u.pci.devfn + (1 << 3);
 		lpc_dev = dev_find_slot(bus_dev->bus->secondary, devfn);
@@ -26,11 +26,12 @@ void amd8111_enable(device_t dev)
 		lpc_dev = dev_find_slot(dev->bus->secondary, devfn);
 		index = dev->path.u.pci.devfn & 7;
 	}
+
 	if ((!lpc_dev) || (index >= 16)) {
 		return;
 	}
 	if ((lpc_dev->vendor != PCI_VENDOR_ID_AMD) ||
-		(lpc_dev->device != PCI_DEVICE_ID_AMD_8111_ISA)) {
+	    (lpc_dev->device != PCI_DEVICE_ID_AMD_8111_ISA)) {
 		uint32_t id;
 		id = pci_read_config32(lpc_dev, PCI_VENDOR_ID);
 		if (id != (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_AMD_8111_ISA << 16))) {
@@ -48,6 +49,6 @@ void amd8111_enable(device_t dev)
 }
 
 struct chip_control southbridge_amd_amd8111_control = {
-	.name       = "AMD 8111",
+	.name       = "AMD 8111 Southbridge",
 	.enable_dev = amd8111_enable,
 };