Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753818AbaBERMN (ORCPT ); Wed, 5 Feb 2014 12:12:13 -0500 Received: from mail-wg0-f53.google.com ([74.125.82.53]:49802 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753086AbaBERFO (ORCPT ); Wed, 5 Feb 2014 12:05:14 -0500 From: Leif Lindholm To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-efi@vger.kernel.org Cc: patches@linaro.org, Mark Salter , Leif Lindholm Subject: [PATCH 03/22] efi: add helper function to get UEFI params from FDT Date: Wed, 5 Feb 2014 17:03:54 +0000 Message-Id: <1391619853-10601-4-git-send-email-leif.lindholm@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1391619853-10601-1-git-send-email-leif.lindholm@linaro.org> References: <1391619853-10601-1-git-send-email-leif.lindholm@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mark Salter ARM and ARM64 architectures use the device tree to pass UEFI parameters from stub to kernel. These parameters are things known to the stub but not discoverable by the kernel after the stub calls ExitBootSerives(). There is a helper function in: drivers/firmware/efi/fdt.c which the stub uses to add the UEFI parameters to the device tree. This patch adds a complimentary helper function which UEFI runtime support may use to retrieve the parameters from the device tree. If an architecture wants to use this helper, it should select CONFIG_UEFI_PARAMS_FROM_FDT. Signed-off-by: Mark Salter Signed-off-by: Leif Lindholm --- drivers/firmware/efi/Kconfig | 7 ++++ drivers/firmware/efi/efi.c | 79 ++++++++++++++++++++++++++++++++++++++++++ include/linux/efi.h | 9 +++++ 3 files changed, 95 insertions(+) diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 1e75f48..d3fe28d 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -47,6 +47,13 @@ config EFI_RUNTIME_MAP See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map. +config UEFI_PARAMS_FROM_FDT + bool + help + Select this config option from the architecture Kconfig if + the EFI runtime support gets system table address, memory + map address, and other parameters from the device tree. + endmenu config UEFI_CPER diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index b25b36b..7f6e977 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -20,6 +20,8 @@ #include #include #include +#include +#include #include struct efi __read_mostly efi = { @@ -318,3 +320,80 @@ int __init efi_config_init(efi_config_table_type_t *arch_tables) return 0; } + +#ifdef CONFIG_UEFI_PARAMS_FROM_FDT + +#define UEFI_PARAM(name, prop, field) \ + { \ + { name }, \ + { prop }, \ + offsetof(struct efi_fdt_params, field), \ + FIELD_SIZEOF(struct efi_fdt_params, field) \ + } + +static __initdata struct { + const char name[32]; + const char propname[32]; + int offset; + int size; +} dt_params[] = { + UEFI_PARAM("System Table", "linux,uefi-system-table", system_table), + UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap), + UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size), + UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size), + UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver) +}; + +struct param_info { + int verbose; + void *params; +}; + +static int __init fdt_find_uefi_params(unsigned long node, const char *uname, + int depth, void *data) +{ + struct param_info *info = data; + void *prop, *dest; + unsigned long len; + u64 val; + int i; + + if (depth != 1 || + (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0)) + return 0; + + pr_info("Getting parameters from FDT:\n"); + + for (i = 0; i < ARRAY_SIZE(dt_params); i++) { + prop = of_get_flat_dt_prop(node, dt_params[i].propname, &len); + if (!prop) { + pr_err("Can't find %s in device tree!\n", + dt_params[i].name); + return 0; + } + dest = info->params + dt_params[i].offset; + + val = of_read_number(prop, len / sizeof(u32)); + + if (dt_params[i].size == sizeof(u32)) + *(u32 *)dest = val; + else + *(u64 *)dest = val; + + if (info->verbose) + pr_info(" %s: 0x%0*llx\n", dt_params[i].name, + dt_params[i].size * 2, val); + } + return 1; +} + +int __init efi_get_fdt_params(struct efi_fdt_params *params, int verbose) +{ + struct param_info info; + + info.verbose = verbose; + info.params = params; + + return of_scan_flat_dt(fdt_find_uefi_params, &info); +} +#endif /* CONFIG_UEFI_PARAMS_FROM_FDT */ diff --git a/include/linux/efi.h b/include/linux/efi.h index a3276da..d450673 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -483,6 +483,14 @@ struct efi_memory_map { unsigned long desc_size; }; +struct efi_fdt_params { + u64 system_table; + u64 mmap; + u32 mmap_size; + u32 desc_size; + u32 desc_ver; +}; + typedef struct { u32 revision; void *parent_handle; @@ -620,6 +628,7 @@ extern void efi_initialize_iomem_resources(struct resource *code_resource, extern void efi_get_time(struct timespec *now); extern int efi_set_rtc_mmss(const struct timespec *now); extern void efi_reserve_boot_services(void); +extern int efi_get_fdt_params(struct efi_fdt_params *params, int verbose); extern struct efi_memory_map memmap; /* Iterate through an efi_memory_map */ -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/