apalis/colibri_t30: implement memory size auto detection

In preparation for the new Apalis T30 SKUs implement memory size auto
detection based on reading the aperture register set by boot ROM from
BCT and a simple mirroring detection.

Tested on initial samples of Apalis T30 1GB V1.0A,
Apalis T30 2GB V1.0B, Apalis T30 2GB V1.0C and Colibri T30 V1.1C.

1 files changed, 32 insertions, 2 deletions

diff --git a/arch/arm/cpu/armv7/tegra-common/board.c b/arch/arm/cpu/armv7/tegra-common/board.c
index 4dbd139838..c2c8be3b9f 100644
--- a/arch/arm/cpu/armv7/tegra-common/board.c
+++ b/arch/arm/cpu/armv7/tegra-common/board.c
@@ -39,7 +39,7 @@ DECLARE_GLOBAL_DATA_PTR;
 
 unsigned int board_query_sdram_size(void)
 {
-#ifndef CONFIG_COLIBRI_T20
+#if !defined(CONFIG_APALIS_T30) && !defined(CONFIG_COLIBRI_T20) && !defined(CONFIG_COLIBRI_T30)
 	struct pmc_ctlr *const pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
 	u32 reg;
 
@@ -63,7 +63,8 @@ unsigned int board_query_sdram_size(void)
 	default:
 		return 0x40000000;	/* 1GB */
 	}
-#else /* CONFIG_COLIBRI_T20 */
+#else /* !CONFIG_APALIS_T30 & !CONFIG_COLIBRI_T20 & !CONFIG_COLIBRI_T30 */
+#ifdef CONFIG_COLIBRI_T20
 	/* Colibri T20 does not use OdmData but rather relies on memory controller
 	   configuration done by boot ROM based on BCT information */
 
@@ -88,7 +89,36 @@ unsigned int board_query_sdram_size(void)
 	}

 
 	return memsize;
+#else /* CONFIG_COLIBRI_T20 */
+	u32 *mc_emem_cfg = (void *)NV_PA_MC_EMEM_CFG_0;
+
+	u32 reg = readl(mc_emem_cfg);
+
+	/* Aperture in MB */
+	u32 memsize = reg * 1024 * 1024;
+
+	/* Unfortunately it is possible to at least boot a 1 GB module with
+	   a 2 GB BCT therefore double check whether we really do have that
+	   amount of physical memory */
+	if (memsize > 1024*1024*1024) {
+		volatile u32 *pMem = (void *)((u32)2048*1024*1024);
+		u32 temp = pMem[0];
+		pMem[0] = 0xabadcafe;
+		asm volatile("" ::: "memory");
+		if (pMem[0] == pMem[1024*1024*1024/4])
+			memsize = 0x40000000;	/* 1GB */
+		else
+			/*
+			 * On tegra3, out of 2GB, 1MB(0xFFF00000 - FFFFFFFF) is used for
+			 * Bootcode(IROM) and arm specific exception vector code.
+			 */
+			memsize = 0x7ff00000;	/* 2GB - 1MB */
+		pMem[0] = temp;
+	}
+
+	return memsize;
 #endif /* CONFIG_COLIBRI_T20 */
+#endif /* !CONFIG_APALIS_T30 & !CONFIG_COLIBRI_T20 & !CONFIG_COLIBRI_T30 */
 }
 
 #if defined(CONFIG_DISPLAY_BOARDINFO) || defined(CONFIG_DISPLAY_BOARDINFO_LATE)