[PATCH v2 12/15] mach-snapdragon: move memory parsing to its own file
Sumit Garg
sumit.garg at kernel.org
Mon May 18 14:54:26 CEST 2026
On Mon, May 04, 2026 at 08:57:40PM +0200, Casey Connolly wrote:
> This code is getting a bit complicated, split it out to try and keep
> things a bit better organised as we're going to be supporting populating
> the memory layout from various other sources.
>
> Signed-off-by: Casey Connolly <casey.connolly at linaro.org>
> ---
> arch/arm/mach-snapdragon/Makefile | 2 +-
> arch/arm/mach-snapdragon/board.c | 115 -------------------------------
> arch/arm/mach-snapdragon/dram.c | 127 +++++++++++++++++++++++++++++++++++
> arch/arm/mach-snapdragon/qcom-priv.h | 2 +
> 4 files changed, 130 insertions(+), 116 deletions(-)
Reviewed-by: Sumit Garg <sumit.garg at oss.qualcomm.com>
-Sumit
>
> diff --git a/arch/arm/mach-snapdragon/Makefile b/arch/arm/mach-snapdragon/Makefile
> index 343e825c6fdd..e481e4f26e5c 100644
> --- a/arch/arm/mach-snapdragon/Makefile
> +++ b/arch/arm/mach-snapdragon/Makefile
> @@ -1,7 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0+
> #
> # (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski at gmail.com>
>
> -obj-y += board.o
> +obj-y += board.o dram.o
> obj-$(CONFIG_EFI_HAVE_CAPSULE_SUPPORT) += capsule_update.o
> obj-$(CONFIG_OF_LIVE) += of_fixup.o
> diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c
> index e12d3d00caa4..a2d97ad77910 100644
> --- a/arch/arm/mach-snapdragon/board.c
> +++ b/arch/arm/mach-snapdragon/board.c
> @@ -42,123 +42,8 @@ enum qcom_boot_source qcom_boot_source __section(".data") = 0;
> static struct mm_region rbx_mem_map[CONFIG_NR_DRAM_BANKS + 2] = { { 0 } };
>
> struct mm_region *mem_map = rbx_mem_map;
>
> -static struct {
> - phys_addr_t start;
> - phys_size_t size;
> -} prevbl_ddr_banks[CONFIG_NR_DRAM_BANKS] __section(".data") = { 0 };
> -
> -int dram_init(void)
> -{
> - /*
> - * gd->ram_base / ram_size have been setup already
> - * in qcom_parse_memory().
> - */
> - return 0;
> -}
> -
> -static int ddr_bank_cmp(const void *v1, const void *v2)
> -{
> - const struct {
> - phys_addr_t start;
> - phys_size_t size;
> - } *res1 = v1, *res2 = v2;
> -
> - if (!res1->size)
> - return 1;
> - if (!res2->size)
> - return -1;
> -
> - return (res1->start >> 24) - (res2->start >> 24);
> -}
> -
> -/* This has to be done post-relocation since gd->bd isn't preserved */
> -static void qcom_configure_bi_dram(void)
> -{
> - int i;
> -
> - for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
> - gd->bd->bi_dram[i].start = prevbl_ddr_banks[i].start;
> - gd->bd->bi_dram[i].size = prevbl_ddr_banks[i].size;
> - }
> -}
> -
> -int dram_init_banksize(void)
> -{
> - qcom_configure_bi_dram();
> -
> - return 0;
> -}
> -
> -/**
> - * The generic memory parsing code in U-Boot lacks a few things that we
> - * need on Qualcomm:
> - *
> - * 1. It sets gd->ram_size and gd->ram_base to represent a single memory block
> - * 2. setup_dest_addr() later relocates U-Boot to ram_base + ram_size, the end
> - * of that first memory block.
> - *
> - * This results in all memory beyond U-Boot being unusable in Linux when booting
> - * with EFI.
> - *
> - * Since the ranges in the memory node may be out of order, the only way for us
> - * to correctly determine the relocation address for U-Boot is to parse all
> - * memory regions and find the highest valid address.
> - *
> - * We can't use fdtdec_setup_memory_banksize() since it stores the result in
> - * gd->bd, which is not yet allocated.
> - *
> - * @fdt: FDT blob to parse /memory node from
> - *
> - * Return: 0 on success or -ENODATA if /memory node is missing or incomplete
> - */
> -static int qcom_parse_memory(const void *fdt)
> -{
> - int offset;
> - const fdt64_t *memory;
> - int memsize;
> - phys_addr_t ram_end = 0;
> - int i, j, banks;
> -
> - offset = fdt_path_offset(fdt, "/memory");
> - if (offset < 0)
> - return -ENODATA;
> -
> - memory = fdt_getprop(fdt, offset, "reg", &memsize);
> - if (!memory)
> - return -ENODATA;
> -
> - banks = min(memsize / (2 * sizeof(u64)), (ulong)CONFIG_NR_DRAM_BANKS);
> -
> - if (memsize / sizeof(u64) > CONFIG_NR_DRAM_BANKS * 2)
> - log_err("Provided more than the max of %d memory banks\n", CONFIG_NR_DRAM_BANKS);
> -
> - if (banks > CONFIG_NR_DRAM_BANKS)
> - log_err("Provided more memory banks than we can handle\n");
> -
> - for (i = 0, j = 0; i < banks * 2; i += 2, j++) {
> - prevbl_ddr_banks[j].start = get_unaligned_be64(&memory[i]);
> - prevbl_ddr_banks[j].size = get_unaligned_be64(&memory[i + 1]);
> - if (!prevbl_ddr_banks[j].size) {
> - j--;
> - continue;
> - }
> - ram_end = max(ram_end, prevbl_ddr_banks[j].start + prevbl_ddr_banks[j].size);
> - }
> -
> - if (!banks || !prevbl_ddr_banks[0].size)
> - return -ENODATA;
> -
> - /* Sort our RAM banks -_- */
> - qsort(prevbl_ddr_banks, banks, sizeof(prevbl_ddr_banks[0]), ddr_bank_cmp);
> -
> - gd->ram_base = prevbl_ddr_banks[0].start;
> - gd->ram_size = ram_end - gd->ram_base;
> -
> - return 0;
> -}
> -
> static void show_psci_version(void)
> {
> struct arm_smccc_res res;
>
> diff --git a/arch/arm/mach-snapdragon/dram.c b/arch/arm/mach-snapdragon/dram.c
> new file mode 100644
> index 000000000000..ad73b685a935
> --- /dev/null
> +++ b/arch/arm/mach-snapdragon/dram.c
> @@ -0,0 +1,127 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Memory layout parsing for Qualcomm.
> + */
> +
> +#define LOG_CATEGORY LOGC_BOARD
> +#define pr_fmt(fmt) "QCOM-DRAM: " fmt
> +
> +#include <asm-generic/unaligned.h>
> +#include <dm.h>
> +#include <log.h>
> +#include <sort.h>
> +
> +static struct {
> + phys_addr_t start;
> + phys_size_t size;
> +} prevbl_ddr_banks[CONFIG_NR_DRAM_BANKS] __section(".data") = { 0 };
> +
> +int dram_init(void)
> +{
> + /*
> + * gd->ram_base / ram_size have been setup already
> + * in qcom_parse_memory().
> + */
> + return 0;
> +}
> +
> +static int ddr_bank_cmp(const void *v1, const void *v2)
> +{
> + const struct {
> + phys_addr_t start;
> + phys_size_t size;
> + } *res1 = v1, *res2 = v2;
> +
> + if (!res1->size)
> + return 1;
> + if (!res2->size)
> + return -1;
> +
> + return (res1->start >> 24) - (res2->start >> 24);
> +}
> +
> +/* This has to be done post-relocation since gd->bd isn't preserved */
> +static void qcom_configure_bi_dram(void)
> +{
> + int i;
> +
> + for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
> + gd->bd->bi_dram[i].start = prevbl_ddr_banks[i].start;
> + gd->bd->bi_dram[i].size = prevbl_ddr_banks[i].size;
> + }
> +}
> +
> +int dram_init_banksize(void)
> +{
> + qcom_configure_bi_dram();
> +
> + return 0;
> +}
> +
> +/**
> + * The generic memory parsing code in U-Boot lacks a few things that we
> + * need on Qualcomm:
> + *
> + * 1. It sets gd->ram_size and gd->ram_base to represent a single memory block
> + * 2. setup_dest_addr() later relocates U-Boot to ram_base + ram_size, the end
> + * of that first memory block.
> + *
> + * This results in all memory beyond U-Boot being unusable in Linux when booting
> + * with EFI.
> + *
> + * Since the ranges in the memory node may be out of order, the only way for us
> + * to correctly determine the relocation address for U-Boot is to parse all
> + * memory regions and find the highest valid address.
> + *
> + * We can't use fdtdec_setup_memory_banksize() since it stores the result in
> + * gd->bd, which is not yet allocated.
> + *
> + * @fdt: FDT blob to parse /memory node from
> + *
> + * Return: 0 on success or -ENODATA if /memory node is missing or incomplete
> + */
> +int qcom_parse_memory(const void *fdt)
> +{
> + int offset;
> + const fdt64_t *memory;
> + int memsize;
> + phys_addr_t ram_end = 0;
> + int i, j, banks;
> +
> + offset = fdt_path_offset(fdt, "/memory");
> + if (offset < 0)
> + return -ENODATA;
> +
> + memory = fdt_getprop(fdt, offset, "reg", &memsize);
> + if (!memory)
> + return -ENODATA;
> +
> + banks = min(memsize / (2 * sizeof(u64)), (ulong)CONFIG_NR_DRAM_BANKS);
> +
> + if (memsize / sizeof(u64) > CONFIG_NR_DRAM_BANKS * 2)
> + log_err("Provided more than the max of %d memory banks\n", CONFIG_NR_DRAM_BANKS);
> +
> + if (banks > CONFIG_NR_DRAM_BANKS)
> + log_err("Provided more memory banks than we can handle\n");
> +
> + for (i = 0, j = 0; i < banks * 2; i += 2, j++) {
> + prevbl_ddr_banks[j].start = get_unaligned_be64(&memory[i]);
> + prevbl_ddr_banks[j].size = get_unaligned_be64(&memory[i + 1]);
> + if (!prevbl_ddr_banks[j].size) {
> + j--;
> + continue;
> + }
> + ram_end = max(ram_end, prevbl_ddr_banks[j].start + prevbl_ddr_banks[j].size);
> + }
> +
> + if (!banks || !prevbl_ddr_banks[0].size)
> + return -ENODATA;
> +
> + /* Sort our RAM banks -_- */
> + qsort(prevbl_ddr_banks, banks, sizeof(prevbl_ddr_banks[0]), ddr_bank_cmp);
> +
> + gd->ram_base = prevbl_ddr_banks[0].start;
> + gd->ram_size = ram_end - gd->ram_base;
> +
> + return 0;
> +}
> diff --git a/arch/arm/mach-snapdragon/qcom-priv.h b/arch/arm/mach-snapdragon/qcom-priv.h
> index b8bf574e8bbb..ce409314a98b 100644
> --- a/arch/arm/mach-snapdragon/qcom-priv.h
> +++ b/arch/arm/mach-snapdragon/qcom-priv.h
> @@ -22,5 +22,7 @@ void qcom_configure_capsule_updates(void);
> #else
> void qcom_configure_capsule_updates(void) {}
> #endif /* EFI_HAVE_CAPSULE_SUPPORT */
>
> +int qcom_parse_memory(const void *fdt);
> +
> #endif /* __QCOM_PRIV_H__ */
>
> --
> 2.53.0
>
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