Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751963Ab3FZOWs (ORCPT ); Wed, 26 Jun 2013 10:22:48 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:43229 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212Ab3FZOWq (ORCPT ); Wed, 26 Jun 2013 10:22:46 -0400 Date: Wed, 26 Jun 2013 16:22:39 +0200 From: Leif Lindholm To: Grant Likely Cc: "linux-arm-kernel@lists.infradead.org" , linux-efi@vger.kernel.org, "linux-doc@vger.kernel.org" , Linux Kernel Mailing List , "patches@linaro.org" , "H. Peter Anvin" , Thomas Gleixner , matt.fleming@intel.com Subject: Re: [PATCH 3/4] arm: Add [U]EFI runtime services support Message-ID: <20130626142239.GD9078@rocoto.smurfnet.nu> References: <1372183863-11333-1-git-send-email-leif.lindholm@linaro.org> <1372183863-11333-4-git-send-email-leif.lindholm@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 18043 Lines: 516 On Wed, Jun 26, 2013 at 02:46:09PM +0100, Grant Likely wrote: > > This patch implements basic support for UEFI runtime services in the > > ARM architecture - a requirement for using efibootmgr to read and update > > the system boot configuration. > > > > It also locates any presented SMBIOS configuration table and stores it > > for potential later use by DMI. > > > > Signed-off-by: Leif Lindholm > > --- > > arch/arm/Kconfig | 15 ++ > > arch/arm/include/asm/efi.h | 22 +++ > > arch/arm/kernel/Makefile | 2 + > > arch/arm/kernel/efi.c | 456 ++++++++++++++++++++++++++++++++++++++++++++ > > arch/arm/kernel/efi_phys.S | 59 ++++++ > > arch/arm/kernel/setup.c | 5 + > > 6 files changed, 559 insertions(+) > > create mode 100644 arch/arm/include/asm/efi.h > > create mode 100644 arch/arm/kernel/efi.c > > create mode 100644 arch/arm/kernel/efi_phys.S > > > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > > index bf8e55d..022d2eb 100644 > > --- a/arch/arm/Kconfig > > +++ b/arch/arm/Kconfig > > @@ -1763,6 +1763,19 @@ config EARLY_IOREMAP > > Provides a mechanism for kernel initialisation code to temporarily > > map, in a highmem-agnostic way, memory pages in before paging_init(). > > > > +config EFI > > +bool "UEFI runtime service support" > > + depends on OF > > + select UCS2_STRING > > + select EARLY_IOREMAP > > + ---help--- > > + This enables the kernel to use UEFI runtime services that are > > + available (such as the UEFI variable services). > > + > > + This option is only useful on systems that have UEFI firmware. > > + However, even with this option, the resultant kernel should > > Be confident! s/should/will/ :-) Ok. > > + continue to boot on existing non-UEFI platforms. > > s/existing// Ok. > > + > > config SECCOMP > > bool > > prompt "Enable seccomp to safely compute untrusted bytecode" > > @@ -2217,6 +2230,8 @@ source "net/Kconfig" > > > > source "drivers/Kconfig" > > > > +source "drivers/firmware/Kconfig" > > + > > source "fs/Kconfig" > > > > source "arch/arm/Kconfig.debug" > > diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h > > new file mode 100644 > > index 0000000..aead94c > > --- /dev/null > > +++ b/arch/arm/include/asm/efi.h > > @@ -0,0 +1,22 @@ > > +#ifndef _ASM_ARM_EFI_H > > +#define _ASM_ARM_EFI_H > > + > > +#include > > + > > +extern int efi_memblock_arm_reserve_range(void); > > + > > +typedef efi_status_t efi_phys_call_t(u32 memory_map_size, > > + u32 descriptor_size, > > + u32 descriptor_version, > > + efi_memory_desc_t *dsc, > > + efi_set_virtual_address_map_t *f); > > + > > +extern efi_status_t efi_phys_call(u32, u32, u32, efi_memory_desc_t *, > > + efi_set_virtual_address_map_t *); > > + > > +#define efi_remap(cookie, size) __arm_ioremap((cookie), (size), MT_MEMORY) > > +#define efi_ioremap(cookie, size) __arm_ioremap((cookie), (size), MT_DEVICE) > > +#define efi_unmap(cookie) __arm_iounmap((cookie)) > > +#define efi_iounmap(cookie) __arm_iounmap((cookie)) > > + > > +#endif /* _ASM_ARM_EFI_H */ > > diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile > > index 5f3338e..12b9c30 100644 > > --- a/arch/arm/kernel/Makefile > > +++ b/arch/arm/kernel/Makefile > > @@ -84,4 +84,6 @@ obj-$(CONFIG_EARLY_PRINTK) += early_printk.o > > obj-$(CONFIG_ARM_VIRT_EXT) += hyp-stub.o > > obj-$(CONFIG_ARM_PSCI) += psci.o > > > > +obj-$(CONFIG_EFI) += efi.o efi_phys.o > > + > > extra-y := $(head-y) vmlinux.lds > > diff --git a/arch/arm/kernel/efi.c b/arch/arm/kernel/efi.c > > new file mode 100644 > > index 0000000..43ecf0b > > --- /dev/null > > +++ b/arch/arm/kernel/efi.c > > @@ -0,0 +1,456 @@ > > +/* > > + * Extensible Firmware Interface > > + * > > + * Based on Extensible Firmware Interface Specification version 2.3.1 > > + * > > + * Copyright (C) 2013 Linaro Ltd. > > Was any of the above code extracted from the x86/ia64 efi code base? > If so then make sure the copyright header and license text gets > retained. Well, some of efi_config_init() was, but it looks like I will be movng it out now. > > + * > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +#include > > +#include > > +#include > > +#include > > + > > +struct efi efi; > > +EXPORT_SYMBOL(efi); > > +struct efi_memory_map memmap; > > The above symbols should be pulled out of x86 and ia64 and made part > of drivers/efi/efi.c. Although in my quick look I don't see memmap > defined for ia64. You'll need to make sure that it actually exists > before moving it. Happy to do that. Can be ifdef'd if need be. > That will also affect your earlier patch which moves > the memmap lookup function. I suspect that function won't build on > ia64. Argh, indeed. I had that ifdef'd ARM/X86, but it seems to have fallen out. > > + > > +static efi_runtime_services_t *runtime; > > + > > +static phys_addr_t efi_system_table; > > +static phys_addr_t efi_boot_mmap; > > +static u32 efi_boot_mmap_size; > > +static u32 efi_mmap_desc_size; > > +static u32 efi_mmap_desc_ver; > > + > > +/* Default memory map descriptor information */ > > +#define DESC_SIZE 48 > > +#define DESC_VER 1 > > + > > +/* If you're planning to wire up a debugger and debug the UEFI side ... */ > > +#undef KEEP_ALL_REGIONS > > +#define KEEP_BOOT_SERVICES_REGIONS > > + > > +static int __initdata uefi_debug; > > +static int __init uefi_debug_setup(char *str) > > +{ > > + uefi_debug = 1; > > + > > + return 0; > > +} > > +early_param("uefi_debug", uefi_debug_setup); > > + > > +static int __init fdt_find_efi_params(unsigned long node, const char *uname, > > + int depth, void *data) > > +{ > > + unsigned long len; > > + __be32 *prop; > > + > > + if (depth != 1 || > > + (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0)) > > + return 0; > > + > > + pr_info("Getting EFI parameters from FDT.\n"); > > + > > + prop = of_get_flat_dt_prop(node, "efi-system-table", &len); > > + if (!prop) > > + return 0; > > + efi_system_table = of_read_ulong(prop, len/4); > > + > > + prop = of_get_flat_dt_prop(node, "efi-runtime-mmap", &len); > > + if (!prop) > > + return 0; > > + efi_boot_mmap = of_read_ulong(prop, len/4); > > + > > + prop = of_get_flat_dt_prop(node, "efi-runtime-mmap-size", &len); > > + if (!prop) > > + return 0; > > + efi_boot_mmap_size = of_read_ulong(prop, len/4); > > + > > + prop = of_get_flat_dt_prop(node, "efi-mmap-desc-size", &len); > > + if (prop) > > + efi_mmap_desc_size = of_read_ulong(prop, len/4); > > + else > > + efi_mmap_desc_size = DESC_SIZE; > > + > > + prop = of_get_flat_dt_prop(node, "efi-mmap-desc-ver", &len); > > + if (prop) > > + efi_mmap_desc_ver = of_read_ulong(prop, len/4); > > + else > > + efi_mmap_desc_ver = DESC_VER; > > As discussed in the binding patch, if the memmap is being passed in > from GRUB, then it can be embedded directly into the device tree which > will change the above code. Yes. > > + > > + if (uefi_debug) { > > + pr_info(" EFI system table @ 0x%08x\n", > > + (unsigned int) efi_system_table); > > + pr_info(" EFI mmap @ 0x%08x\n", > > + (unsigned int) efi_boot_mmap); > > + pr_info(" EFI mmap size = 0x%08x\n", > > + (unsigned int) efi_boot_mmap_size); > > + pr_info(" EFI mmap descriptor size = 0x%08x\n", > > + (unsigned int) efi_mmap_desc_size); > > + pr_info(" EFI mmap descriptor version = 0x%08x\n", > > + (unsigned int) efi_mmap_desc_ver); > > + } > > + > > + return 1; > > +} > > + > > +static int __init uefi_config_init(void) > > +{ > > + efi_char16_t *c16; > > + char vendor[100] = "unknown"; > > + efi_config_table_t *config_tables; > > + u32 nr_tables; > > + int i; > > + > > + efi.systab = early_ioremap(efi_system_table, > > + sizeof(efi_system_table_t)); > > + > > + /* > > + * Verify the EFI Table > > + */ > > + if (efi.systab == NULL) > > + panic("Whoa! Can't find EFI system table.\n"); > > + if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) > > + panic("Whoa! EFI system table signature incorrect\n"); > > + if ((efi.systab->hdr.revision >> 16) == 0) > > + pr_warn("Warning: EFI system table version %d.%02d, expected 1.00 or greater\n", > > + efi.systab->hdr.revision >> 16, > > + efi.systab->hdr.revision & 0xffff); > > + > > + /* Show what we know for posterity */ > > + c16 = (efi_char16_t *)early_ioremap(efi.systab->fw_vendor, > > + sizeof(vendor)); > > + if (c16) { > > + for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i) > > + vendor[i] = c16[i]; > > + vendor[i] = '\0'; > > + } > > + > > + pr_info("EFI v%u.%.02u by %s\n", > > + efi.systab->hdr.revision >> 16, > > + efi.systab->hdr.revision & 0xffff, vendor); > > + > > + > > + nr_tables = efi.systab->nr_tables; > > + > > + config_tables = early_ioremap(efi.systab->tables, > > + sizeof(efi_config_table_t) * nr_tables); > > + > > + for (i = 0; i < nr_tables; i++) { > > + efi_guid_t guid; > > + unsigned long table; > > + u8 str[38]; > > + > > + guid = config_tables[i].guid; > > + table = config_tables[i].table; > > + > > + efi_guid_unparse(&guid, str); > > + if (uefi_debug) > > + pr_info(" Config Table: UUID=%s @ 0x%08x\n", > > + str, (u32)table); > > + if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) > > + efi.smbios = table; > > + } > > + > > + early_iounmap(config_tables, sizeof(efi_config_table_t) * nr_tables); > > + early_iounmap(c16, sizeof(vendor)); > > + early_iounmap(efi.systab, sizeof(efi_system_table_t)); > > + > > + return 0; > > +} > > + > > +static __init int is_discardable_region(efi_memory_desc_t *md) > > +{ > > +#ifdef KEEP_ALL_REGIONS > > + return 0; > > +#endif > > + > > + if (md->attribute & EFI_MEMORY_RUNTIME) > > + return 0; > > + > > + switch (md->type) { > > +#ifdef KEEP_BOOT_SERVICES_REGIONS > > + case EFI_BOOT_SERVICES_CODE: > > + case EFI_BOOT_SERVICES_DATA: > > +#endif > > + /* Keep tables around for any future kexec operations */ > > + case EFI_ACPI_RECLAIM_MEMORY: > > + return 0; > > + } > > + > > + return 1; > > +} > > + > > +static __initdata struct { > > + u32 type; > > + const char *name; > > +} memory_type_name_map[] = { > > + {EFI_RESERVED_TYPE, "EFI reserved"}, > > + {EFI_LOADER_CODE, "EFI loader code"}, > > + {EFI_LOADER_DATA, "EFI loader data"}, > > + {EFI_BOOT_SERVICES_CODE, "EFI boot services code"}, > > + {EFI_BOOT_SERVICES_DATA, "EFI boot services data"}, > > + {EFI_RUNTIME_SERVICES_CODE, "EFI runtime services code"}, > > + {EFI_RUNTIME_SERVICES_DATA, "EFI runtime services data"}, > > + {EFI_CONVENTIONAL_MEMORY, "EFI conventional memory"}, > > + {EFI_UNUSABLE_MEMORY, "EFI unusable memory"}, > > + {EFI_ACPI_RECLAIM_MEMORY, "EFI ACPI reclaim memory"}, > > + {EFI_ACPI_MEMORY_NVS, "EFI ACPI memory nvs"}, > > + {EFI_MEMORY_MAPPED_IO, "EFI memory mapped I/O"}, > > + {EFI_MEMORY_MAPPED_IO_PORT_SPACE, "EFI memory mapped I/O port space"}, > > + {EFI_PAL_CODE, "EFI pal code"}, > > + {EFI_MAX_MEMORY_TYPE, NULL}, > > +}; > > The above *definitely* belongs in common code! :-) > > > + > > +static __init void remove_sections(phys_addr_t addr, unsigned long size) > > +{ > > + unsigned long section_offset; > > + unsigned long num_sections; > > + > > + section_offset = addr - (addr & SECTION_MASK); > > + num_sections = size / SECTION_SIZE; > > + if (size % SECTION_SIZE) > > + num_sections++; > > + > > + memblock_remove(addr - section_offset, num_sections * SECTION_SIZE); > > +} > > + > > +static __init int remove_regions(void) > > +{ > > + efi_memory_desc_t *md; > > + int count = 0; > > + > > + void *p; > > + > > + memmap.phys_map = early_ioremap(efi_boot_mmap, efi_boot_mmap_size); > > + > > + memmap.desc_size = efi_mmap_desc_size; > > + memmap.desc_version = efi_mmap_desc_ver; > > + memmap.map_end = (void *) memmap.phys_map + efi_boot_mmap_size; > > + memmap.nr_map = 0; > > + > > + if (uefi_debug) > > + pr_info("Processing EFI memory map:\n"); > > + > > + for (p = memmap.phys_map; p < memmap.map_end; p += memmap.desc_size) { > > + md = p; > > + if (is_discardable_region(md)) > > + continue; > > + > > + if (uefi_debug) > > + pr_info(" %8llu pages @ %016llx (%s)\n", > > + md->num_pages, md->phys_addr, > > + memory_type_name_map[md->type].name); > > + > > + if (md->type != EFI_MEMORY_MAPPED_IO) { > > + remove_sections(md->phys_addr, > > + md->num_pages * PAGE_SIZE); > > + count++; > > + } > > + memmap.nr_map++; > > + } > > + > > + if (uefi_debug) > > + pr_info("%d regions preserved.\n", memmap.nr_map); > > + > > + early_iounmap(memmap.phys_map, efi_boot_mmap_size); > > + > > + return 0; > > +} > > + > > +int __init efi_memblock_arm_reserve_range(void) > > +{ > > + /* Grab system table location out of FDT (or ACPI) */ > > + of_scan_flat_dt(fdt_find_efi_params, NULL); > > + > > + if (!efi_system_table || !efi_boot_mmap || !efi_boot_mmap_size) > > + return 0; > > + > > + remove_regions(); > > + > > + uefi_config_init(); > > + > > + return 0; > > +} > > + > > +/* > > + * Disable instrrupts, enable idmap and disable caches. > > + */ > > +static void __init phys_call_prologue(void) > > +{ > > + local_irq_disable(); > > + > > + /* Take out a flat memory mapping. */ > > + setup_mm_for_reboot(); > > + > > + /* Clean and invalidate caches */ > > + flush_cache_all(); > > + > > + /* Turn off caching */ > > + cpu_proc_fin(); > > + > > + /* Push out any further dirty data, and ensure cache is empty */ > > + flush_cache_all(); > > +} > > + > > +/* > > + * Restore original memory map and re-enable interrupts. > > + */ > > +static void __init phys_call_epilogue(void) > > +{ > > + static struct mm_struct *mm = &init_mm; > > + > > + /* Restore original memory mapping */ > > + cpu_switch_mm(mm->pgd, mm); > > + > > + /* Flush branch predictor and TLBs */ > > + local_flush_bp_all(); > > +#ifdef CONFIG_CPU_HAS_ASID > > + local_flush_tlb_all(); > > +#endif > > + > > + local_irq_enable(); > > +} > > + > > +/* > > + * This function switches the EFI runtime services to virtual mode. > > + * This operation must be performed only once in the system's lifetime, > > + * including any kecec calls. > > + * > > + * This must be done with a 1:1 mapping. The current implementation > > + * resolves this by disabling the MMU. > > + */ > > +efi_status_t __init phys_set_virtual_address_map(u32 memory_map_size, > > + u32 descriptor_size, > > + u32 descriptor_version, > > + efi_memory_desc_t *dsc) > > +{ > > + efi_phys_call_t *phys_set_map; > > + efi_status_t status; > > + > > + phys_call_prologue(); > > + > > + phys_set_map = (void *)(unsigned long)virt_to_phys(efi_phys_call); > > + > > + /* Called with caches disabled, returns with caches enabled */ > > + status = phys_set_map(memory_map_size, descriptor_size, > > + descriptor_version, dsc, > > + efi.set_virtual_address_map); > > + > > + phys_call_epilogue(); > > + > > + return status; > > +} > > Eventually we'll need to look at how this interacts with kexec. A > kexec'd kernel will need to use the mapping already chosen by a > previous kernel, but that's an issue for another patch series. Yes please :] > The patch needs some rework, but otherwise looks good, although I'm > concerned about duplicate code. However, I've not dug deep into the > mmu handling code. Others more cluefull that I on the MMU details will > need to weigh in on that. Thanks. / Leif -- 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/