diff options
-rw-r--r-- | target/linux/ramips/patches-4.14/105-mt7621-memory-detect.patch | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-4.14/105-mt7621-memory-detect.patch b/target/linux/ramips/patches-4.14/105-mt7621-memory-detect.patch new file mode 100644 index 0000000000..b19b57fd66 --- /dev/null +++ b/target/linux/ramips/patches-4.14/105-mt7621-memory-detect.patch @@ -0,0 +1,125 @@ +From b5a52351a66f3c2a7a207548aa87d78ff2d336c0 Mon Sep 17 00:00:00 2001 +From: Chuanhong Guo <gch981213@gmail.com> +Date: Wed, 10 Jul 2019 00:24:48 +0800 +Subject: [PATCH] MIPS: ralink: mt7621: add memory detection support + +mt7621 has the following memory map: +0x0-0x1c000000: lower 448m memory +0x1c000000-0x2000000: peripheral registers +0x20000000-0x2400000: higher 64m memory + +detect_memory_region in arch/mips/kernel/setup.c only add the first +memory region and isn't suitable for 512m memory detection because +it may accidentally read the memory area for peripheral registers. + +This commit adds memory detection capability for mt7621: +1. add the highmem area when 512m is detected. +2. guard memcmp from accessing peripheral registers: + This only happens when some weird user decided to change + kernel load address to 256m or higher address. Since this + is a quite unusual case, we just skip 512m testing and return + 256m as memory size. + +Signed-off-by: Chuanhong Guo <gch981213@gmail.com> +--- + arch/mips/include/asm/mach-ralink/mt7621.h | 7 ++--- + arch/mips/ralink/mt7621.c | 30 +++++++++++++++++++--- + 2 files changed, 30 insertions(+), 7 deletions(-) + +--- a/arch/mips/include/asm/mach-ralink/mt7621.h ++++ b/arch/mips/include/asm/mach-ralink/mt7621.h +@@ -46,9 +46,10 @@ + #define CPU_PLL_FBDIV_MASK 0x7f + #define CPU_PLL_FBDIV_SHIFT 4 + +-#define MT7621_DRAM_BASE 0x0 +-#define MT7621_DDR2_SIZE_MIN 32 +-#define MT7621_DDR2_SIZE_MAX 256 ++#define MT7621_LOWMEM_BASE 0x0 ++#define MT7621_LOWMEM_MAX_SIZE 0x1C000000 ++#define MT7621_HIGHMEM_BASE 0x20000000 ++#define MT7621_HIGHMEM_SIZE 0x4000000 + + #define MT7621_CHIP_NAME0 0x3637544D + #define MT7621_CHIP_NAME1 0x20203132 +--- a/arch/mips/ralink/mt7621.c ++++ b/arch/mips/ralink/mt7621.c +@@ -15,6 +15,7 @@ + #include <linux/clk-provider.h> + #include <dt-bindings/clock/mt7621-clk.h> + ++#include <asm/bootinfo.h> + #include <asm/mipsregs.h> + #include <asm/smp-ops.h> + #include <asm/mips-cps.h> +@@ -57,6 +58,8 @@ + #define MT7621_GPIO_MODE_SDHCI_SHIFT 18 + #define MT7621_GPIO_MODE_SDHCI_GPIO 1 + ++static void *detect_magic __initdata = detect_memory_region; ++ + static struct rt2880_pmx_func uart1_grp[] = { FUNC("uart1", 0, 1, 2) }; + static struct rt2880_pmx_func i2c_grp[] = { FUNC("i2c", 0, 3, 2) }; + static struct rt2880_pmx_func uart3_grp[] = { +@@ -141,6 +144,28 @@ static struct clk *__init mt7621_add_sys + return clk; + } + ++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 (!memcmp(dm, dm + size, sizeof(detect_magic))) ++ break; ++ } ++ ++ if ((size == 256 * SZ_1M) && ++ (CPHYSADDR(dm + size) < MT7621_LOWMEM_MAX_SIZE) && ++ 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); ++ } ++} ++ + void __init ralink_clk_init(void) + { + u32 syscfg, xtal_sel, clkcfg, clk_sel, curclk, ffiv, ffrac; +@@ -319,10 +344,7 @@ void prom_soc_init(struct ralink_soc_inf + (rev >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK, + (rev & CHIP_REV_ECO_MASK)); + +- soc_info->mem_size_min = MT7621_DDR2_SIZE_MIN; +- soc_info->mem_size_max = MT7621_DDR2_SIZE_MAX; +- soc_info->mem_base = MT7621_DRAM_BASE; +- ++ soc_info->mem_detect = mt7621_memory_detect; + rt2880_pinmux_data = mt7621_pinmux_data; + + +--- a/arch/mips/ralink/common.h ++++ b/arch/mips/ralink/common.h +@@ -19,6 +19,7 @@ struct ralink_soc_info { + unsigned long mem_size; + unsigned long mem_size_min; + unsigned long mem_size_max; ++ void (*mem_detect)(void); + }; + extern struct ralink_soc_info soc_info; + +--- a/arch/mips/ralink/of.c ++++ b/arch/mips/ralink/of.c +@@ -89,6 +89,8 @@ void __init plat_mem_setup(void) + of_scan_flat_dt(early_init_dt_find_memory, NULL); + if (memory_dtb) + of_scan_flat_dt(early_init_dt_scan_memory, NULL); ++ else if (soc_info.mem_detect) ++ soc_info.mem_detect(); + else if (soc_info.mem_size) + add_memory_region(soc_info.mem_base, soc_info.mem_size * SZ_1M, + BOOT_MEM_RAM); |