Fixes to the smbus code. Now for the fun.

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1165 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

src/southbridge/via/vt8231/vt8231_early_smbus.c

@@ -1,17 +1,31 @@
 #define SMBUS_IO_BASE 0x5000
 
-#define SMBGSTATUS 0xe0
+#define SMBHSTSTAT 0x0
-#define SMBGCTL    0xe2
+#define SMBSLVSTAT 0x1
-#define SMBHSTADDR 0xe4
+#define SMBHSTCTL  0x2
-#define SMBHSTDAT  0xe6
+#define SMBHSTCMD  0x3
-#define SMBHSTCMD  0xe8
+#define SMBXMITADD 0x4
-#define SMBHSTFIFO 0xe9
+#define SMBHSTDAT0 0x5
+#define SMBHSTDAT1 0x6
+#define SMBBLKDAT  0x7
+#define SMBSLVCTL  0x8
+#define SMBTRNSADD 0x9
+#define SMBSLVDATA 0xa
+#define SMLINK_PIN_CTL 0xe
+#define SMBUS_PIN_CTL  0xf 
+
+/* Define register settings */
+#define HOST_RESET 0xff
+#define DIMM_BASE 0xa0        // 1010000 is base for DIMM in SMBus
+#define READ_CMD  0x01        // 1 in the 0 bit of SMBHSTADD states to READ
+
 
 #define SMBUS_TIMEOUT (100*1000*10)
 
 static void enable_smbus(void)
 {
   device_t dev;
+  unsigned char c;
   /* Power management controller */
   dev = pci_locate_device(PCI_ID(0x1106,0x8235), 0);
 
@@ -23,7 +37,13 @@ static void enable_smbus(void)
   pci_write_config32(dev, 0x90, SMBUS_IO_BASE|1);
 
   // Enable SMBus 
-	pci_write_config8(dev, 0xd2, 0x01);
+  c = pci_read_config8(dev, 0xd2);
+  c |= 5;
+  pci_write_config8(dev, 0xd2, c);
+
+  c = pci_read_config8(dev, 0x54);
+  c &= ~0x80;
+  pci_write_config8(dev, 0xd2, c);
 
 
   print_debug("SMBus controller enabled\r\n");
@@ -40,75 +60,163 @@ static int smbus_wait_until_ready(void)
   unsigned long loops;
   loops = SMBUS_TIMEOUT;
   do {
-		unsigned short val;
+    unsigned char val;
     smbus_delay();
-		val = inw(SMBUS_IO_BASE + SMBGSTATUS);
+    c = my_inb(smbus_io_base + SMBHSTSTAT);
-		if ((val & 0x800) == 0) {
+    while((c & 1) == 1) {
-			break;
+      printk_err("c is 0x%x\n", c);
+      c = my_inb(smbus_io_base + SMBHSTSTAT);
+      /* nop */ 
     }
+
   } while(--loops);
   return loops?0:-1;
 }
 
+void smbus_reset(void)
+{
+  my_outb(HOST_RESET, smbus_io_base + SMBHSTSTAT);
+  my_outb(HOST_RESET, smbus_io_base + SMBHSTSTAT);
+  my_outb(HOST_RESET, smbus_io_base + SMBHSTSTAT);
+  my_outb(HOST_RESET, smbus_io_base + SMBHSTSTAT);
+
+  smbus_wait_until_ready();
+  printk_err("After reset status %#x\n", my_inb(smbus_io_base + SMBHSTSTAT));
+}
+  
+
+
 static int smbus_wait_until_done(void)
 {
   unsigned long loops;
   loops = SMBUS_TIMEOUT;
   do {
-		unsigned short val;
+    unsigned char val;
     smbus_delay();
 		
-		val = inw(SMBUS_IO_BASE + SMBGSTATUS);
+    byte = my_inb(smbus_io_base + SMBHSTSTAT);
-		if (((val & 0x8) == 0) | ((val & 0x437) != 0)) {
+    if (byte & 1)
       break;
-		}
+
   } while(--loops);
   return loops?0:-1;
 }
 
-static int smbus_read_byte(unsigned device, unsigned address)
+static void smbus_print_error(unsigned char host_status_register)
 {
-	unsigned char global_control_register;
+
-	unsigned char global_status_register;
+  printk_err("smbus_error: 0x%02x\n", host_status_register);
+  if (host_status_register & (1 << 4)) {
+    printk_err("Interrup/SMI# was Failed Bus Transaction\n");
+  }
+  if (host_status_register & (1 << 3)) {
+    printk_err("Bus Error\n");
+  }
+  if (host_status_register & (1 << 2)) {
+    printk_err("Device Error\n");
+  }
+  if (host_status_register & (1 << 1)) {
+    printk_err("Interrupt/SMI# was Successful Completion\n");
+  }
+  if (host_status_register & (1 << 0)) {
+    printk_err("Host Busy\n");
+  }
+}
+
+
+/* SMBus routines borrowed from VIA's Trident Driver */
+/* this works, so I am not going to touch it for now -- rgm */
+static unsigned char smbus_read(unsigned char devAdr, unsigned char bIndex, 
+				unsigned char *result)
+{
+  unsigned short i;
+  unsigned char  bData;
+  unsigned char  sts;
+		        
+  /* clear host status */
+  my_outb(0xff, smbus_io_base);
+			    
+  /* check SMBUS ready */
+  for ( i = 0; i < 0xFFFF; i++ )
+    if ( (my_inb(smbus_io_base) & 0x01) == 0 )
+      break;
+
+  /* set host command */
+  my_outb(bIndex, smbus_io_base+3);
+
+  /* set slave address */
+  my_outb(devAdr | 0x01, smbus_io_base+4);
+
+  /* start */
+  my_outb(0x48, smbus_io_base+2);
+
+  /* SMBUS Wait Ready */
+  for ( i = 0; i < 0xFFFF; i++ )
+    if ( ((sts = my_inb(smbus_io_base)) & 0x01) == 0 )
+      break;
+  if ((sts & ~3) != 0) {
+    smbus_print_error(sts);
+    return 0;
+  }
+  bData=my_inb(smbus_io_base+5);
+
+  *result = bData;
+
+  /* return 1 if ok */
+  return 1;
+
+}
+
+/* for reference, here is the fancier version which we will use at some 
+ * point
+ */
+# if 0
+int smbus_read_byte(unsigned device, unsigned address, unsigned char *result)
+{
+  unsigned char host_status_register;
   unsigned char byte;
 
-	if (smbus_wait_until_ready() < 0) {
+  reset();
-		return -1;
+
-	}
+  smbus_wait_until_ready();
 
   /* setup transaction */
   /* disable interrupts */
-	outw(inw(SMBUS_IO_BASE + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)), SMBUS_IO_BASE + SMBGCTL);
+  my_outb(my_inb(smbus_io_base + SMBHSTCTL) & (~1), smbus_io_base + SMBHSTCTL);
   /* set the device I'm talking too */
-	outw(((device & 0x7f) << 1) | 1, SMBUS_IO_BASE + SMBHSTADDR);
+  my_outb(((device & 0x7f) << 1) | 1, smbus_io_base + SMBXMITADD);
   /* set the command/address... */
-	outb(address & 0xFF, SMBUS_IO_BASE + SMBHSTCMD);
+  my_outb(address & 0xFF, smbus_io_base + SMBHSTCMD);
   /* set up for a byte data read */
-	outw((inw(SMBUS_IO_BASE + SMBGCTL) & ~7) | (0x2), SMBUS_IO_BASE + SMBGCTL);
+  my_outb((my_inb(smbus_io_base + SMBHSTCTL) & 0xE3) | (0x2 << 2),
+	  smbus_io_base + SMBHSTCTL);
 
   /* clear any lingering errors, so the transaction will run */
-	/* Do I need to write the bits to a 1 to clear an error? */
+  my_outb(my_inb(smbus_io_base + SMBHSTSTAT), smbus_io_base + SMBHSTSTAT);
-	outw(inw(SMBUS_IO_BASE + SMBGSTATUS), SMBUS_IO_BASE + SMBGSTATUS);
 
-	/* clear the data word...*/
+  /* clear the data byte...*/
-	outw(0, SMBUS_IO_BASE + SMBHSTDAT);
+  my_outb(0, smbus_io_base + SMBHSTDAT0);
 
   /* start the command */
-	outw((inw(SMBUS_IO_BASE + SMBGCTL) | (1 << 3)), SMBUS_IO_BASE + SMBGCTL);
+  my_outb((my_inb(smbus_io_base + SMBHSTCTL) | 0x40),
-
+	  smbus_io_base + SMBHSTCTL);
 
   /* poll for transaction completion */
-	if (smbus_wait_until_done() < 0) {
+  smbus_wait_until_done();
-		return -1;
-	}
 
-	global_status_register = inw(SMBUS_IO_BASE + SMBGSTATUS);
+  host_status_register = my_inb(smbus_io_base + SMBHSTSTAT);
+
+  /* Ignore the In Use Status... */
+  host_status_register &= ~(1 << 6);
 
   /* read results of transaction */
-	byte = inw(SMBUS_IO_BASE + SMBHSTDAT) & 0xff;
+  byte = my_inb(smbus_io_base + SMBHSTDAT0);
+  smbus_print_error(byte);
 
-	if (global_status_register != (1 << 4)) {
+  *result = byte;
-		return -1;
+  return host_status_register != 0x02;
-	}
-	return byte;
 }
+
+
+#endif
+