tegra: Add tegra_get_chip_type() to detect SKU

We want to know which type of chip we are running on - the Tegra
family has several SKUs. This can be determined by reading a
fuse register, so add this function to ap20.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>

arch/arm/cpu/armv7/tegra2/ap20.c

@@ -26,11 +26,47 @@
 #include <asm/arch/ap20.h>
 #include <asm/arch/clk_rst.h>
 #include <asm/arch/clock.h>
+#include <asm/arch/fuse.h>
+#include <asm/arch/gp_padctrl.h>
 #include <asm/arch/pmc.h>
 #include <asm/arch/pinmux.h>
 #include <asm/arch/scu.h>
 #include <common.h>
 
+int tegra_get_chip_type(void)
+{
+	struct apb_misc_gp_ctlr *gp;
+	struct fuse_regs *fuse = (struct fuse_regs *)TEGRA2_FUSE_BASE;
+	uint tegra_sku_id, rev;
+
+	/*
+	 * This is undocumented, Chip ID is bits 15:8 of the register
+	 * APB_MISC + 0x804, and has value 0x20 for Tegra20, 0x30 for
+	 * Tegra30
+	 */
+	gp = (struct apb_misc_gp_ctlr *)TEGRA2_APB_MISC_GP_BASE;
+	rev = (readl(&gp->hidrev) & HIDREV_CHIPID_MASK) >> HIDREV_CHIPID_SHIFT;
+
+	tegra_sku_id = readl(&fuse->sku_info) & 0xff;
+
+	switch (rev) {
+	case CHIPID_TEGRA2:
+		switch (tegra_sku_id) {
+		case SKU_ID_T20:
+			return TEGRA_SOC_T20;
+		case SKU_ID_T25SE:
+		case SKU_ID_AP25:
+		case SKU_ID_T25:
+		case SKU_ID_AP25E:
+		case SKU_ID_T25E:
+			return TEGRA_SOC_T25;
+		}
+		break;
+	}
+	/* unknown sku id */
+	return TEGRA_SOC_UNKNOWN;
+}
+
 /* Returns 1 if the current CPU executing is a Cortex-A9, else 0 */
 static int ap20_cpu_is_cortexa9(void)
 {

arch/arm/include/asm/arch-tegra2/ap20.h

@@ -100,3 +100,10 @@ void tegra2_start(void);
 
 /* This is the main entry into U-Boot, used by the Cortex-A9 */
 extern void _start(void);
+
+/**
+ * Works out the SOC type used for clocks settings
+ *
+ * @return	SOC type - see TEGRA_SOC...
+ */
+int tegra_get_chip_type(void);

arch/arm/include/asm/arch-tegra2/gp_padctrl.h

@@ -61,4 +61,13 @@ struct apb_misc_gp_ctlr {
 	u32	memcomp;	/* 0xD4: APB_MISC_GP_MEMCOMPPADCTRL */
 };
 
+/* bit fields definitions for APB_MISC_GP_HIDREV register */
+#define HIDREV_CHIPID_SHIFT		8
+#define HIDREV_CHIPID_MASK		(0xff << HIDREV_CHIPID_SHIFT)
+#define HIDREV_MAJORPREV_SHIFT		4
+#define HIDREV_MAJORPREV_MASK		(0xf << HIDREV_MAJORPREV_SHIFT)
+
+/* CHIPID field returned from APB_MISC_GP_HIDREV register */
+#define CHIPID_TEGRA2				0x20
+
 #endif

arch/arm/include/asm/arch-tegra2/tegra2.h

@@ -33,6 +33,7 @@
 #define NV_PA_GPIO_BASE		0x6000D000
 #define NV_PA_EVP_BASE		0x6000F000
 #define NV_PA_APB_MISC_BASE	0x70000000
+#define TEGRA2_APB_MISC_GP_BASE	(NV_PA_APB_MISC_BASE + 0x0800)
 #define NV_PA_APB_UARTA_BASE	(NV_PA_APB_MISC_BASE + 0x6000)
 #define NV_PA_APB_UARTB_BASE	(NV_PA_APB_MISC_BASE + 0x6040)
 #define NV_PA_APB_UARTC_BASE	(NV_PA_APB_MISC_BASE + 0x6200)
@@ -55,6 +56,29 @@
 struct timerus {
 	unsigned int cntr_1us;
 };
+
+/* Address at which WB code runs, it must not overlap Bootrom's IRAM usage */
+#define AP20_WB_RUN_ADDRESS	0x40020000
+
+/* These are the available SKUs (product types) for Tegra */
+enum {
+	SKU_ID_T20		= 0x8,
+	SKU_ID_T25SE		= 0x14,
+	SKU_ID_AP25		= 0x17,
+	SKU_ID_T25		= 0x18,
+	SKU_ID_AP25E		= 0x1b,
+	SKU_ID_T25E		= 0x1c,
+};
+
+/* These are the SOC categories that affect clocking */
+enum {
+	TEGRA_SOC_T20,
+	TEGRA_SOC_T25,
+
+	TEGRA_SOC_COUNT,
+	TEGRA_SOC_UNKNOWN	= -1,
+};
+
 #else  /* __ASSEMBLY__ */
 #define PRM_RSTCTRL		TEGRA2_PMC_BASE
 #endif