diff options
Diffstat (limited to 'arch/arm/mach-omap/emif4.c')
| -rw-r--r-- | arch/arm/mach-omap/emif4.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/arm/mach-omap/emif4.c b/arch/arm/mach-omap/emif4.c index e61cf00c57..b5a53e8c63 100644 --- a/arch/arm/mach-omap/emif4.c +++ b/arch/arm/mach-omap/emif4.c @@ -65,6 +65,56 @@ #define EMIF4_DDR1_PWRDN_EN (0x1 << 6) #define EMIF4_DDR1_READ_LAT (0x6 << 0) +/** + * emif4_sdram_size - read back SDRAM size from sdram_config register + * + * @return: The SDRAM size + */ +unsigned long emif4_sdram_size(const void __iomem *emif4) +{ + uint32_t sdram_config = readl(emif4 + EMIF4_SDRAM_CONFIG); + int rows, cols, width, banks; + unsigned long size; + + rows = ((sdram_config >> 7) & 0x7) + 9; + cols = (sdram_config & 0x7) + 8; + + switch ((sdram_config >> 14) & 0x3) { + case 0: + width = 4; + break; + case 1: + width = 2; + break; + default: + return 0; + } + + switch ((sdram_config >> 4) & 0x7) { + case 0: + banks = 1; + break; + case 1: + banks = 2; + break; + case 2: + banks = 4; + break; + case 3: + banks = 8; + break; + default: + return 0; + } + + size = (1 << rows) * (1 << cols) * banks * width; + + debug("SDRAM_CONFIG: 0x%08x, cols: %2d, rows: %2d, width: %2d, banks: %2d, size: 0x%08lx\n", + sdram_config, cols, rows, width, banks, size); + + return size; +} + /* * - Init the emif4 module for DDR access * - Early init routines, called from flash or SRAM. |