Add patches for M53EVK which make the DRAM access in U-Boot much faster. Please see u-boot/m53evk/0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch commit message for complete explanation of the issue and it's resolution.
Signed-off-by: Marek Vasut <[email protected]> Cc: Wolfgang Denk <[email protected]> --- ...004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch | 63 ++++++++++++ ...5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch | 111 +++++++++++++++++++++ meta-eldk/recipes-bsp/uboot/u-boot_2014.01.bb | 2 + 3 files changed, 176 insertions(+) create mode 100644 meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch create mode 100644 meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0005-arm-mx5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch diff --git a/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch b/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch new file mode 100644 index 0000000..94e9cfe --- /dev/null +++ b/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch @@ -0,0 +1,63 @@ +From 07469fd3ae3c64dbc9d014c92a3ca74cd97aa297 Mon Sep 17 00:00:00 2001 +From: Marek Vasut <[email protected]> +Date: Fri, 28 Mar 2014 04:45:16 +0100 +Subject: [PATCH 1/2] arm: mx5: Fix memory slowness on M53EVK + +Fix memory access slowness on i.MX53 M53EVK board. Let us inspect the +issue: First of all, the i.MX53 CPU has two memory banks mapped at +0x7000_0000 and 0xb000_0000 and each of those can hold up to 1GiB of +DRAM memory. Notice that the memory area is not continuous. On M53EVK, +each of the banks contain 512MiB of DRAM, which makes a total of 1GiB +of memory available to the system. + +The problem is how the relocation of U-Boot is treated on i.MX53 . The +U-Boot is placed at the ((start of first DRAM partition) + (gd->ram_size)) . +This in turn poses a problem, since in our case, the gd->ram_size is 1GiB, +the first DRAM bank starts at 0x7000_0000 and contains 512MiB of memory. +Thus, with this algorithm, U-Boot is placed at offset: + + 0x7000_0000 + 1GiB - sizeof(u-boot and some small margin) + +This is past the DRAM available in the first bank on M53EVK, but is still +within the address range of the first DRAM bank. Because of the memory +wrap-around, the data can still be read and written to this area, but the +access is much slower. + +There were two ideas how to solve this problem, first was to map both of +the available DRAM chunks next to one another by using MMU, second was to +define CONFIG_VERY_BIG_RAM and CONFIG_MAX_MEM_MAPPED to size of the memory +in the first DRAM bank. We choose the later because it turns out the former +is not applicable afterall. The former cannot be used in case Linux kernel +was loaded into the second DRAM bank area, which would be remapped and one +would try booting the kernel, since at some point before the kernel is started, +the MMU would be turned off, which would destroy the mapping and hang the +system. + +Signed-off-by: Marek Vasut <[email protected]> +Cc: Fabio Estevam <[email protected]> +Cc: Stefano Babic <[email protected]> +Cc: Wolfgang Denk <[email protected]> + +V2: Reword the commit message +--- + include/configs/m53evk.h | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +diff --git a/include/configs/m53evk.h b/include/configs/m53evk.h +index 9d41e75..d592318 100644 +--- a/include/configs/m53evk.h ++++ b/include/configs/m53evk.h +@@ -62,7 +62,9 @@ + #define PHYS_SDRAM_SIZE (PHYS_SDRAM_1_SIZE + PHYS_SDRAM_2_SIZE) + #define CONFIG_SYS_MALLOC_LEN (10 * 1024 * 1024) + #define CONFIG_SYS_MEMTEST_START 0x70000000 +-#define CONFIG_SYS_MEMTEST_END 0xaff00000 ++#define CONFIG_SYS_MEMTEST_END 0x8ff00000 ++#define CONFIG_VERY_BIG_RAM ++#define CONFIG_MAX_MEM_MAPPED PHYS_SDRAM_1_SIZE + + #define CONFIG_SYS_SDRAM_BASE (PHYS_SDRAM_1) + #define CONFIG_SYS_INIT_RAM_ADDR (IRAM_BASE_ADDR) +-- +1.9.0 + diff --git a/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0005-arm-mx5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch b/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0005-arm-mx5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch new file mode 100644 index 0000000..c6a7806 --- /dev/null +++ b/meta-eldk/recipes-bsp/uboot/u-boot/m53evk/0005-arm-mx5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch @@ -0,0 +1,111 @@ +From 62bb0c9ef2772474d741f88c85f29e666f955e63 Mon Sep 17 00:00:00 2001 +From: Marek Vasut <[email protected]> +Date: Fri, 28 Mar 2014 05:09:23 +0100 +Subject: [PATCH 2/2] arm: mx5: Avoid hardcoding memory sizes on M53EVK + +The DRAM size can be easily detected at runtime on i.MX53. Implement +such detection on M53EVK and adjust the rest of the macros accordingly +to use the detected values. + +An important thing to note here is that we had to override the function +for trimming the effective DRAM address, get_effective_memsize(). That +is because the function uses CONFIG_MAX_MEM_MAPPED as the upper bound of +the available DRAM and we don't have gd->bd->bi_dram[0].size set up at +the time the function is called, thus we cannot put this into the macro +CONFIG_MAX_MEM_MAPPED . Instead, we use custom override where we use the +size of the first DRAM block which we just detected. + +Signed-off-by: Marek Vasut <[email protected]> +Cc: Fabio Estevam <[email protected]> +Cc: Stefano Babic <[email protected]> +Cc: Wolfgang Denk <[email protected]> + +V2: Use linux/sizes.h instead of asm/sizes.h +V3: - Drop use of sizes.h completely + - Add beefy comment as to why we override get_effective_memsize() + - Drop CONFIG_VERY_BIG_RAM and CONFIG_MAX_MEM_MAPPED as we no longer + need it if we override get_effective_memsize() +--- + board/denx/m53evk/m53evk.c | 31 ++++++++++++++++++++++++------- + include/configs/m53evk.h | 8 +++----- + 2 files changed, 27 insertions(+), 12 deletions(-) + +diff --git a/board/denx/m53evk/m53evk.c b/board/denx/m53evk/m53evk.c +index 0f71a16..74f9501 100644 +--- a/board/denx/m53evk/m53evk.c ++++ b/board/denx/m53evk/m53evk.c +@@ -31,24 +31,41 @@ + + DECLARE_GLOBAL_DATA_PTR; + +-int dram_init(void) ++static uint32_t mx53_dram_size[2]; ++ ++phys_size_t get_effective_memsize(void) + { +- u32 size1, size2; ++ /* ++ * WARNING: We must override get_effective_memsize() function here ++ * to report only the size of the first DRAM bank. This is to make ++ * U-Boot relocator place U-Boot into valid memory, that is, at the ++ * end of the first DRAM bank. If we did not override this function ++ * like so, U-Boot would be placed at the address of the first DRAM ++ * bank + total DRAM size - sizeof(uboot), which in the setup where ++ * each DRAM bank contains 512MiB of DRAM would result in placing ++ * U-Boot into invalid memory area close to the end of the first ++ * DRAM bank. ++ */ ++ return mx53_dram_size[0]; ++} + +- size1 = get_ram_size((void *)PHYS_SDRAM_1, PHYS_SDRAM_1_SIZE); +- size2 = get_ram_size((void *)PHYS_SDRAM_2, PHYS_SDRAM_2_SIZE); ++int dram_init(void) ++{ ++ mx53_dram_size[0] = get_ram_size((void *)PHYS_SDRAM_1, 1 << 30); ++ mx53_dram_size[1] = get_ram_size((void *)PHYS_SDRAM_2, 1 << 30); + +- gd->ram_size = size1 + size2; ++ gd->ram_size = mx53_dram_size[0] + mx53_dram_size[1]; + + return 0; + } ++ + void dram_init_banksize(void) + { + gd->bd->bi_dram[0].start = PHYS_SDRAM_1; +- gd->bd->bi_dram[0].size = PHYS_SDRAM_1_SIZE; ++ gd->bd->bi_dram[0].size = mx53_dram_size[0]; + + gd->bd->bi_dram[1].start = PHYS_SDRAM_2; +- gd->bd->bi_dram[1].size = PHYS_SDRAM_2_SIZE; ++ gd->bd->bi_dram[1].size = mx53_dram_size[1]; + } + + static void setup_iomux_uart(void) +diff --git a/include/configs/m53evk.h b/include/configs/m53evk.h +index d592318..1324877 100644 +--- a/include/configs/m53evk.h ++++ b/include/configs/m53evk.h +@@ -56,15 +56,13 @@ + */ + #define CONFIG_NR_DRAM_BANKS 2 + #define PHYS_SDRAM_1 CSD0_BASE_ADDR +-#define PHYS_SDRAM_1_SIZE (512 * 1024 * 1024) ++#define PHYS_SDRAM_1_SIZE (gd->bd->bi_dram[0].size) + #define PHYS_SDRAM_2 CSD1_BASE_ADDR +-#define PHYS_SDRAM_2_SIZE (512 * 1024 * 1024) +-#define PHYS_SDRAM_SIZE (PHYS_SDRAM_1_SIZE + PHYS_SDRAM_2_SIZE) ++#define PHYS_SDRAM_2_SIZE (gd->bd->bi_dram[1].size) ++#define PHYS_SDRAM_SIZE (gd->ram_size) + #define CONFIG_SYS_MALLOC_LEN (10 * 1024 * 1024) + #define CONFIG_SYS_MEMTEST_START 0x70000000 + #define CONFIG_SYS_MEMTEST_END 0x8ff00000 +-#define CONFIG_VERY_BIG_RAM +-#define CONFIG_MAX_MEM_MAPPED PHYS_SDRAM_1_SIZE + + #define CONFIG_SYS_SDRAM_BASE (PHYS_SDRAM_1) + #define CONFIG_SYS_INIT_RAM_ADDR (IRAM_BASE_ADDR) +-- +1.9.0 + diff --git a/meta-eldk/recipes-bsp/uboot/u-boot_2014.01.bb b/meta-eldk/recipes-bsp/uboot/u-boot_2014.01.bb index 7010cd3..e521dec 100644 --- a/meta-eldk/recipes-bsp/uboot/u-boot_2014.01.bb +++ b/meta-eldk/recipes-bsp/uboot/u-boot_2014.01.bb @@ -26,6 +26,8 @@ SRC_URI_append_m53evk = " \ file://0001-ARM-m53evk-add-needed-commands-and-options.patch \ file://0002-ARM-m53evk-Adjust-mtdparts-settings.patch \ file://0003-ARM-m53evk-Update-default-environment.patch \ + file://0004-arm-mx5-Fix-memory-slowness-on-M53EVK.patch \ + file://0005-arm-mx5-Avoid-hardcoding-memory-sizes-on-M53EVK.patch \ " # Build u-boot-with-nand-spl.imx for the M53EVK so we can place it in the image -- 1.9.0 _______________________________________________ eldk mailing list [email protected] http://lists.denx.de/mailman/listinfo/eldk
