Tilapila supports both dual slot and single slot. The difference should be

detected by the existence of dev3. Some other RS780 mainboard has 
the same function. The patch added the function to make these boards work
smoothly.

Signed-off-by: Wang Qing Pei <wangqingpei@gmail.com>
Acked-by: Zheng Bao <zheng.bao@amd.com>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@5714 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

src/mainboard/amd/mahogany/mainboard.c

@@ -34,7 +34,7 @@ uint64_t uma_memory_base, uma_memory_size;
 
 void set_pcie_dereset(void);
 void set_pcie_reset(void);
-
+u8 is_dev3_present(void);
 /*
  * Mahogany uses GPIO 6 as PCIe slot reset, GPIO4 as GFX slot reset. We need to
  * pull it up before training the slot.
@@ -94,6 +94,10 @@ static void get_ide_dma66(void)
 }
 #endif	/* get_ide_dma66 */
 
+u8 is_dev3_present(void)
+{
+	return 0;
+}
 /*************************************************
 * enable the dedicated function in mahogany board.
 * This function called early than rs780_enable.

src/mainboard/amd/mahogany_fam10/mainboard.c

@@ -34,7 +34,7 @@ uint64_t uma_memory_base, uma_memory_size;
 
 void set_pcie_dereset(void);
 void set_pcie_reset(void);
-
+u8 is_dev3_present(void);
 /*
  * Mahogany uses GPIO 6 as PCIe slot reset, GPIO4 as GFX slot reset. We need to
  * pull it up before training the slot.
@@ -94,6 +94,11 @@ static void get_ide_dma66(void)
 }
 #endif	/* get_ide_dma66() */
 
+u8 is_dev3_present(void)
+{
+	return 0;
+}
+
 /*************************************************
 * enable the dedicated function in mahogany board.
 * This function called early than rs780_enable.

src/mainboard/amd/tilapia_fam10/mainboard.c

@@ -48,6 +48,7 @@ uint64_t uma_memory_base, uma_memory_size;
 
 void set_pcie_dereset(void);
 void set_pcie_reset(void);
+u8 is_dev3_present(void);
 
 void set_pcie_dereset()
 {
@@ -129,6 +130,90 @@ static void get_ide_dma66(void)
 }
 #endif
 
+/*
+ * justify the dev3 is exist or not
+ */
+u8 is_dev3_present(void)
+{
+	u16 word;
+	device_t sm_dev;
+
+	/* access the smbus extended register */
+	sm_dev = dev_find_slot(0, PCI_DEVFN(0x14, 0));
+
+	/* put the GPIO68 output to tristate */
+	word = pci_read_config16(sm_dev, 0x7e);
+	word |= 1 << 6;
+	pci_write_config16(sm_dev, 0x7e,word);
+
+	/* read the GPIO68 input status */
+	word = pci_read_config16(sm_dev, 0x7e);
+
+	if(word & (1 << 10)){
+		/*not exist*/
+		return 0;
+	}else{
+		/*exist*/
+		return 1;
+	}
+}
+
+
+/*
+ * set gpio40 gfx
+ */
+static void set_gpio40_gfx(void)
+{
+	u8 byte;
+	u32 dword;
+	device_t sm_dev;
+	/* disable the GPIO40 as CLKREQ2# function */
+	byte = pm_ioread(0xd3);
+	byte &= ~(1 << 7);
+	pm_iowrite(0xd3, byte);
+
+	/* disable the GPIO40 as CLKREQ3# function */
+	byte = pm_ioread(0xd4);
+	byte &= ~(1 << 0);
+	pm_iowrite(0xd4, byte);
+
+	/* enable pull up for GPIO68 */
+	byte = pm2_ioread(0xf1);
+	byte &=	~(1 << 4);
+	pm2_iowrite(0xf1, byte);
+
+	/* access the smbus extended register */
+	sm_dev = dev_find_slot(0, PCI_DEVFN(0x14, 0));
+
+	/*if the dev3 is present, set the gfx to 2x8 lanes*/
+	/*otherwise set the gfx to 1x16 lanes*/
+	if(is_dev3_present()){
+
+		printk(BIOS_INFO, "Dev3 is present. GFX Configuration is Two x8 slots\n");
+		/* when the gpio40 is configured as GPIO, this will enable the output */
+		pci_write_config32(sm_dev, 0xf8, 0x4);
+		dword = pci_read_config32(sm_dev, 0xfc);
+		dword &= ~(1 << 10);
+
+	        /* When the gpio40 is configured as GPIO, this will represent the output value*/
+		/* 1 :enable two x8  , 0 : master slot enable only */
+		dword |= (1 << 26);
+		pci_write_config32(sm_dev, 0xfc, dword);
+
+	}else{
+		printk(BIOS_INFO, "Dev3 is not present. GFX Configuration is One x16 slot\n");
+		/* when the gpio40 is configured as GPIO, this will enable the output */
+		pci_write_config32(sm_dev, 0xf8, 0x4);
+		dword = pci_read_config32(sm_dev, 0xfc);
+		dword &= ~(1 << 10);
+
+        	/* When the gpio40 is configured as GPIO, this will represent the output value*/
+		/* 1 :enable two x8  , 0 : master slot enable only */
+		dword &=  ~(1 << 26);
+		pci_write_config32(sm_dev, 0xfc, dword);
+	}
+}
+
 /*
  * set thermal config
  */
@@ -247,6 +332,7 @@ static void tilapia_enable(device_t dev)
 	set_pcie_dereset();
 	/* get_ide_dma66(); */
 	set_thermal_config();
+	set_gpio40_gfx();
 }
 
 int add_mainboard_resources(struct lb_memory *mem)

src/mainboard/asrock/939a785gmh/mainboard.c

@@ -34,7 +34,7 @@ uint64_t uma_memory_base, uma_memory_size;
 
 void set_pcie_dereset(void);
 void set_pcie_reset(void);
-
+u8 is_dev3_present(void);
 /*
  * Mahogany uses GPIO 6 as PCIe slot reset, GPIO4 as GFX slot reset. We need to
  * pull it up before training the slot.
@@ -94,6 +94,11 @@ static void get_ide_dma66(void)
 }
 #endif	/* get_ide_dma66 */
 
+u8 is_dev3_present(void)
+{
+	return 0;
+}
+
 /*************************************************
 * enable the dedicated function in mahogany board.
 * This function called early than rs780_enable.

src/southbridge/amd/rs780/rs780_gfx.c

@@ -35,7 +35,7 @@
 #include <delay.h>
 #include <cpu/x86/msr.h>
 #include "rs780.h"
-
+extern int is_dev3_present(void);
 void set_pcie_reset(void);
 void set_pcie_dereset(void);
 
@@ -1214,6 +1214,40 @@ void rs780_gfx_init(device_t nb_dev, device_t dev, u32 port)
 		printk(BIOS_DEBUG, "device = %x\n", dev->path.pci.devfn >> 3);
 		dual_port_configuration(nb_dev, dev);
 		break;
+
+	case 2:
+
+		if(is_dev3_present()){
+			/* step 1, lane reversal (only need if CMOS option is enabled) */
+			if (cfg->gfx_lane_reversal) {
+				set_nbmisc_enable_bits(nb_dev, 0x33, 1 << 2, 1 << 2);
+				set_nbmisc_enable_bits(nb_dev, 0x33, 1 << 3, 1 << 3);
+			}
+			printk(BIOS_DEBUG, "rs780_gfx_init step1.\n");
+			/* step 1.1, dual-slot gfx configuration (only need if CMOS option is enabled) */
+			/* AMD calls the configuration CrossFire */
+			set_nbmisc_enable_bits(nb_dev, 0x0, 0xf << 8, 5 << 8);
+			printk(BIOS_DEBUG, "rs780_gfx_init step2.\n");
+
+
+			printk(BIOS_DEBUG, "device = %x\n", dev->path.pci.devfn >> 3);
+			dual_port_configuration(nb_dev, dev);
+
+		}else{
+			if (cfg->gfx_lane_reversal) {
+				set_nbmisc_enable_bits(nb_dev, 0x33, 1 << 2, 1 << 2);
+			}
+			printk(BIOS_DEBUG, "rs780_gfx_init step1.\n");
+			printk(BIOS_DEBUG, "rs780_gfx_init step2.\n");
+
+			if((dev->path.pci.devfn >> 3) == 2)
+				single_port_configuration(nb_dev, dev);
+			else{
+				set_nbmisc_enable_bits(nb_dev, 0xc, 0, 0x2 << 2); /* hide the GFX bridge. */
+				printk(BIOS_DEBUG, "If dev3.., single port. Do nothing.\n");
+			    }
+		}
+
 	default:
 		printk(BIOS_INFO, "Incorrect configuration of external GFX slot.\n");
 		break;