diff --git a/arch/arm/include/asm/arch-sunxi/dram.h b/arch/arm/include/asm/arch-sunxi/dram.h index 0eccb1e6c28..59e2e980bfa 100644 --- a/arch/arm/include/asm/arch-sunxi/dram.h +++ b/arch/arm/include/asm/arch-sunxi/dram.h @@ -45,5 +45,6 @@ unsigned long sunxi_dram_init(void); void mctl_await_completion(u32 *reg, u32 mask, u32 val); bool mctl_mem_matches(u32 offset); bool mctl_mem_matches_base(u32 offset, ulong base); +bool mctl_check_memory(phys_addr_t addr); #endif /* _SUNXI_DRAM_H */ diff --git a/arch/arm/mach-sunxi/dram_dw_helpers.c b/arch/arm/mach-sunxi/dram_dw_helpers.c index 24767354935..d2af2d57fde 100644 --- a/arch/arm/mach-sunxi/dram_dw_helpers.c +++ b/arch/arm/mach-sunxi/dram_dw_helpers.c @@ -143,8 +143,28 @@ void mctl_auto_detect_dram_size(const struct dram_para *para, unsigned long mctl_calc_size(const struct dram_config *config) { + unsigned long size; u8 width = config->bus_full_width ? 4 : 2; /* 8 banks */ - return (1ULL << (config->cols + config->rows + 3)) * width * config->ranks; + size = (1ULL << (config->cols + config->rows + 3)) * width * + config->ranks; + + /* + * There are boards with non-power-of-2 sized DRAM chips, like 1.5GB + * or 3GB. They are detected as the larger power-of-2 (2GB and 4GB), + * so test the last quarter for being able to store values. + */ + if (!mctl_check_memory(CFG_SYS_SDRAM_BASE + size / 4 * 3)) { + if (mctl_check_memory(CFG_SYS_SDRAM_BASE + size / 4 * 3 - 64)) { + size = (size / 4) * 3; + debug("capping memory at %ld MB\n", size >> 20); + } else { + printf("DRAM test failure at address 0x%lx\n", + CFG_SYS_SDRAM_BASE + size / 4 * 3 - 64); + return 0; + } + } + + return size; } diff --git a/arch/arm/mach-sunxi/dram_helpers.c b/arch/arm/mach-sunxi/dram_helpers.c index 83dbe4ca98f..376b7d14f86 100644 --- a/arch/arm/mach-sunxi/dram_helpers.c +++ b/arch/arm/mach-sunxi/dram_helpers.c @@ -62,3 +62,15 @@ bool mctl_mem_matches(u32 offset) return mctl_mem_matches_base(offset, CFG_SYS_SDRAM_BASE); } #endif + +bool mctl_check_memory(phys_addr_t addr) +{ + uint32_t orig, val; + + orig = readl(addr); + writel(~orig, addr); + val = readl(addr); + writel(orig, addr); + + return ~orig == val; +}