diff options
Diffstat (limited to 'target/linux/ramips')
| -rw-r--r-- | target/linux/ramips/patches-5.4/325-mt7621-fix-memory-detect.patch | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-5.4/325-mt7621-fix-memory-detect.patch b/target/linux/ramips/patches-5.4/325-mt7621-fix-memory-detect.patch new file mode 100644 index 0000000000..f8616c31fc --- /dev/null +++ b/target/linux/ramips/patches-5.4/325-mt7621-fix-memory-detect.patch @@ -0,0 +1,62 @@ +--- a/arch/mips/ralink/mt7621.c ++++ b/arch/mips/ralink/mt7621.c +@@ -58,7 +58,9 @@ + #define MT7621_GPIO_MODE_SDHCI_SHIFT 18 + #define MT7621_GPIO_MODE_SDHCI_GPIO 1 + +-static void *detect_magic __initdata = detect_memory_region; ++#define MT7621_MEM_TEST_PATTERN 0xaa5555aa ++ ++static u32 detect_magic __initdata; + + static struct rt2880_pmx_func uart1_grp[] = { FUNC("uart1", 0, 1, 2) }; + static struct rt2880_pmx_func i2c_grp[] = { FUNC("i2c", 0, 3, 2) }; +@@ -144,26 +146,34 @@ static struct clk *__init mt7621_add_sys + return clk; + } + ++static bool __init mt7621_addr_wraparound_test(phys_addr_t size) ++{ ++ void *dm = (void *)KSEG1ADDR(&detect_magic); ++ if (CPHYSADDR(dm + size) >= MT7621_LOWMEM_MAX_SIZE) ++ return true; ++ __raw_writel(MT7621_MEM_TEST_PATTERN, dm); ++ if (__raw_readl(dm) != __raw_readl(dm + size)) ++ return false; ++ __raw_writel(!MT7621_MEM_TEST_PATTERN, dm); ++ return __raw_readl(dm) == __raw_readl(dm + size); ++} ++ + void __init mt7621_memory_detect(void) + { +- void *dm = &detect_magic; + phys_addr_t size; + +- for (size = 32 * SZ_1M; size < 256 * SZ_1M; size <<= 1) { +- if (!__builtin_memcmp(dm, dm + size, sizeof(detect_magic))) +- break; ++ for (size = 32 * SZ_1M; size <= 256 * SZ_1M; size <<= 1) { ++ if (mt7621_addr_wraparound_test(size)) { ++ add_memory_region(MT7621_LOWMEM_BASE, size, BOOT_MEM_RAM); ++ return; ++ } + } + +- if ((size == 256 * SZ_1M) && +- (CPHYSADDR(dm + size) < MT7621_LOWMEM_MAX_SIZE) && +- __builtin_memcmp(dm, dm + size, sizeof(detect_magic))) { +- add_memory_region(MT7621_LOWMEM_BASE, MT7621_LOWMEM_MAX_SIZE, +- BOOT_MEM_RAM); +- add_memory_region(MT7621_HIGHMEM_BASE, MT7621_HIGHMEM_SIZE, +- BOOT_MEM_RAM); +- } else { +- add_memory_region(MT7621_LOWMEM_BASE, size, BOOT_MEM_RAM); +- } ++ /* addr doesn't wrap around at dm + 256M, assume 512M memory. */ ++ add_memory_region(MT7621_LOWMEM_BASE, MT7621_LOWMEM_MAX_SIZE, ++ BOOT_MEM_RAM); ++ add_memory_region(MT7621_HIGHMEM_BASE, MT7621_HIGHMEM_SIZE, ++ BOOT_MEM_RAM); + } + + void __init ralink_clk_init(void) |