summaryrefslogtreecommitdiffstats
path: root/drivers/firmware
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2020-10-20 03:18:30 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2020-10-20 03:18:30 +0200
commit270315b8235e3d10c2e360cff56c2f9e0915a252 (patch)
tree17a178c0f6c08026579c6c9f510a3dc0a01785da /drivers/firmware
parentMerge tag 'm68knommu-for-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/... (diff)
parentRISC-V: Add page table dump support for uefi (diff)
downloadlinux-270315b8235e3d10c2e360cff56c2f9e0915a252.tar.xz
linux-270315b8235e3d10c2e360cff56c2f9e0915a252.zip
Merge tag 'riscv-for-linus-5.10-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt: "A handful of cleanups and new features: - A handful of cleanups for our page fault handling - Improvements to how we fill out cacheinfo - Support for EFI-based systems" * tag 'riscv-for-linus-5.10-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (22 commits) RISC-V: Add page table dump support for uefi RISC-V: Add EFI runtime services RISC-V: Add EFI stub support. RISC-V: Add PE/COFF header for EFI stub RISC-V: Implement late mapping page table allocation functions RISC-V: Add early ioremap support RISC-V: Move DT mapping outof fixmap RISC-V: Fix duplicate included thread_info.h riscv/mm/fault: Set FAULT_FLAG_INSTRUCTION flag in do_page_fault() riscv/mm/fault: Fix inline placement in vmalloc_fault() declaration riscv: Add cache information in AUX vector riscv: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO riscv: Set more data to cacheinfo riscv/mm/fault: Move access error check to function riscv/mm/fault: Move FAULT_FLAG_WRITE handling in do_page_fault() riscv/mm/fault: Simplify mm_fault_error() riscv/mm/fault: Move fault error handling to mm_fault_error() riscv/mm/fault: Simplify fault error handling riscv/mm/fault: Move vmalloc fault handling to vmalloc_fault() riscv/mm/fault: Move bad area handling to bad_area() ...
Diffstat (limited to 'drivers/firmware')
-rw-r--r--drivers/firmware/efi/Kconfig3
-rw-r--r--drivers/firmware/efi/Makefile2
-rw-r--r--drivers/firmware/efi/libstub/Makefile10
-rw-r--r--drivers/firmware/efi/libstub/efi-stub.c11
-rw-r--r--drivers/firmware/efi/libstub/riscv-stub.c109
-rw-r--r--drivers/firmware/efi/riscv-runtime.c143
6 files changed, 276 insertions, 2 deletions
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index da1887f72a51..36ec1f718893 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -106,7 +106,7 @@ config EFI_GENERIC_STUB
config EFI_ARMSTUB_DTB_LOADER
bool "Enable the DTB loader"
- depends on EFI_GENERIC_STUB
+ depends on EFI_GENERIC_STUB && !RISCV
default y
help
Select this config option to add support for the dtb= command
@@ -123,6 +123,7 @@ config EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER
bool "Enable the command line initrd loader" if !X86
depends on EFI_STUB && (EFI_GENERIC_STUB || X86)
default y
+ depends on !RISCV
help
Select this config option to add support for the initrd= command
line parameter, allowing an initrd that resides on the same volume
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index e8da782280b6..d6ca2da19339 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -36,6 +36,8 @@ fake_map-$(CONFIG_X86) += x86_fake_mem.o
arm-obj-$(CONFIG_EFI) := efi-init.o arm-runtime.o
obj-$(CONFIG_ARM) += $(arm-obj-y)
obj-$(CONFIG_ARM64) += $(arm-obj-y)
+riscv-obj-$(CONFIG_EFI) := efi-init.o riscv-runtime.o
+obj-$(CONFIG_RISCV) += $(riscv-obj-y)
obj-$(CONFIG_EFI_CAPSULE_LOADER) += capsule-loader.o
obj-$(CONFIG_EFI_EARLYCON) += earlycon.o
obj-$(CONFIG_UEFI_CPER_ARM) += cper-arm.o
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 039a9acab817..8a94388e38b3 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -23,6 +23,8 @@ cflags-$(CONFIG_ARM64) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
cflags-$(CONFIG_ARM) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
-fno-builtin -fpic \
$(call cc-option,-mno-single-pic-base)
+cflags-$(CONFIG_RISCV) := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
+ -fpic
cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt
@@ -64,6 +66,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \
lib-$(CONFIG_ARM) += arm32-stub.o
lib-$(CONFIG_ARM64) += arm64-stub.o
lib-$(CONFIG_X86) += x86-stub.o
+lib-$(CONFIG_RISCV) += riscv-stub.o
CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
# Even when -mbranch-protection=none is set, Clang will generate a
@@ -112,6 +115,13 @@ STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \
--prefix-symbols=__efistub_
STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS
+# For RISC-V, we don't need anything special other than arm64. Keep all the
+# symbols in .init section and make sure that no absolute symbols references
+# doesn't exist.
+STUBCOPY_FLAGS-$(CONFIG_RISCV) += --prefix-alloc-sections=.init \
+ --prefix-symbols=__efistub_
+STUBCOPY_RELOC-$(CONFIG_RISCV) := R_RISCV_HI20
+
$(obj)/%.stub.o: $(obj)/%.o FORCE
$(call if_changed,stubcopy)
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index 311a16802dd6..914a343c7785 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -17,7 +17,10 @@
/*
* This is the base address at which to start allocating virtual memory ranges
- * for UEFI Runtime Services. This is in the low TTBR0 range so that we can use
+ * for UEFI Runtime Services.
+ *
+ * For ARM/ARM64:
+ * This is in the low TTBR0 range so that we can use
* any allocation we choose, and eliminate the risk of a conflict after kexec.
* The value chosen is the largest non-zero power of 2 suitable for this purpose
* both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can
@@ -25,6 +28,12 @@
* Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split,
* map everything below 1 GB. (512 MB is a reasonable upper bound for the
* entire footprint of the UEFI runtime services memory regions)
+ *
+ * For RISC-V:
+ * There is no specific reason for which, this address (512MB) can't be used
+ * EFI runtime virtual address for RISC-V. It also helps to use EFI runtime
+ * services on both RV32/RV64. Keep the same runtime virtual address for RISC-V
+ * as well to minimize the code churn.
*/
#define EFI_RT_VIRTUAL_BASE SZ_512M
#define EFI_RT_VIRTUAL_SIZE SZ_512M
diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c
new file mode 100644
index 000000000000..380e4e251399
--- /dev/null
+++ b/drivers/firmware/efi/libstub/riscv-stub.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Western Digital Corporation or its affiliates.
+ */
+
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+
+#include <asm/efi.h>
+#include <asm/sections.h>
+
+#include "efistub.h"
+
+/*
+ * RISC-V requires the kernel image to placed 2 MB aligned base for 64 bit and
+ * 4MB for 32 bit.
+ */
+#ifdef CONFIG_64BIT
+#define MIN_KIMG_ALIGN SZ_2M
+#else
+#define MIN_KIMG_ALIGN SZ_4M
+#endif
+
+typedef void __noreturn (*jump_kernel_func)(unsigned int, unsigned long);
+
+static u32 hartid;
+
+static u32 get_boot_hartid_from_fdt(void)
+{
+ const void *fdt;
+ int chosen_node, len;
+ const fdt32_t *prop;
+
+ fdt = get_efi_config_table(DEVICE_TREE_GUID);
+ if (!fdt)
+ return U32_MAX;
+
+ chosen_node = fdt_path_offset(fdt, "/chosen");
+ if (chosen_node < 0)
+ return U32_MAX;
+
+ prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len);
+ if (!prop || len != sizeof(u32))
+ return U32_MAX;
+
+ return fdt32_to_cpu(*prop);
+}
+
+efi_status_t check_platform_features(void)
+{
+ hartid = get_boot_hartid_from_fdt();
+ if (hartid == U32_MAX) {
+ efi_err("/chosen/boot-hartid missing or invalid!\n");
+ return EFI_UNSUPPORTED;
+ }
+ return EFI_SUCCESS;
+}
+
+void __noreturn efi_enter_kernel(unsigned long entrypoint, unsigned long fdt,
+ unsigned long fdt_size)
+{
+ unsigned long stext_offset = _start_kernel - _start;
+ unsigned long kernel_entry = entrypoint + stext_offset;
+ jump_kernel_func jump_kernel = (jump_kernel_func)kernel_entry;
+
+ /*
+ * Jump to real kernel here with following constraints.
+ * 1. MMU should be disabled.
+ * 2. a0 should contain hartid
+ * 3. a1 should DT address
+ */
+ csr_write(CSR_SATP, 0);
+ jump_kernel(hartid, fdt);
+}
+
+efi_status_t handle_kernel_image(unsigned long *image_addr,
+ unsigned long *image_size,
+ unsigned long *reserve_addr,
+ unsigned long *reserve_size,
+ efi_loaded_image_t *image)
+{
+ unsigned long kernel_size = 0;
+ unsigned long preferred_addr;
+ efi_status_t status;
+
+ kernel_size = _edata - _start;
+ *image_addr = (unsigned long)_start;
+ *image_size = kernel_size + (_end - _edata);
+
+ /*
+ * RISC-V kernel maps PAGE_OFFSET virtual address to the same physical
+ * address where kernel is booted. That's why kernel should boot from
+ * as low as possible to avoid wastage of memory. Currently, dram_base
+ * is occupied by the firmware. So the preferred address for kernel to
+ * boot is next aligned address. If preferred address is not available,
+ * relocate_kernel will fall back to efi_low_alloc_above to allocate
+ * lowest possible memory region as long as the address and size meets
+ * the alignment constraints.
+ */
+ preferred_addr = MIN_KIMG_ALIGN;
+ status = efi_relocate_kernel(image_addr, kernel_size, *image_size,
+ preferred_addr, MIN_KIMG_ALIGN, 0x0);
+
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to relocate kernel\n");
+ *image_size = 0;
+ }
+ return status;
+}
diff --git a/drivers/firmware/efi/riscv-runtime.c b/drivers/firmware/efi/riscv-runtime.c
new file mode 100644
index 000000000000..d28e715d2bcc
--- /dev/null
+++ b/drivers/firmware/efi/riscv-runtime.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Extensible Firmware Interface
+ *
+ * Copyright (C) 2020 Western Digital Corporation or its affiliates.
+ *
+ * Based on Extensible Firmware Interface Specification version 2.4
+ * Adapted from drivers/firmware/efi/arm-runtime.c
+ *
+ */
+
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <linux/memblock.h>
+#include <linux/mm_types.h>
+#include <linux/preempt.h>
+#include <linux/rbtree.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/pgtable.h>
+
+#include <asm/cacheflush.h>
+#include <asm/efi.h>
+#include <asm/mmu.h>
+#include <asm/pgalloc.h>
+
+static bool __init efi_virtmap_init(void)
+{
+ efi_memory_desc_t *md;
+
+ efi_mm.pgd = pgd_alloc(&efi_mm);
+ mm_init_cpumask(&efi_mm);
+ init_new_context(NULL, &efi_mm);
+
+ for_each_efi_memory_desc(md) {
+ phys_addr_t phys = md->phys_addr;
+ int ret;
+
+ if (!(md->attribute & EFI_MEMORY_RUNTIME))
+ continue;
+ if (md->virt_addr == 0)
+ return false;
+
+ ret = efi_create_mapping(&efi_mm, md);
+ if (ret) {
+ pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
+ &phys, ret);
+ return false;
+ }
+ }
+
+ if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
+ return false;
+
+ return true;
+}
+
+/*
+ * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
+ * non-early mapping of the UEFI system table and virtual mappings for all
+ * EFI_MEMORY_RUNTIME regions.
+ */
+static int __init riscv_enable_runtime_services(void)
+{
+ u64 mapsize;
+
+ if (!efi_enabled(EFI_BOOT)) {
+ pr_info("EFI services will not be available.\n");
+ return 0;
+ }
+
+ efi_memmap_unmap();
+
+ mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
+
+ if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
+ pr_err("Failed to remap EFI memory map\n");
+ return 0;
+ }
+
+ if (efi_soft_reserve_enabled()) {
+ efi_memory_desc_t *md;
+
+ for_each_efi_memory_desc(md) {
+ int md_size = md->num_pages << EFI_PAGE_SHIFT;
+ struct resource *res;
+
+ if (!(md->attribute & EFI_MEMORY_SP))
+ continue;
+
+ res = kzalloc(sizeof(*res), GFP_KERNEL);
+ if (WARN_ON(!res))
+ break;
+
+ res->start = md->phys_addr;
+ res->end = md->phys_addr + md_size - 1;
+ res->name = "Soft Reserved";
+ res->flags = IORESOURCE_MEM;
+ res->desc = IORES_DESC_SOFT_RESERVED;
+
+ insert_resource(&iomem_resource, res);
+ }
+ }
+
+ if (efi_runtime_disabled()) {
+ pr_info("EFI runtime services will be disabled.\n");
+ return 0;
+ }
+
+ if (efi_enabled(EFI_RUNTIME_SERVICES)) {
+ pr_info("EFI runtime services access via paravirt.\n");
+ return 0;
+ }
+
+ pr_info("Remapping and enabling EFI services.\n");
+
+ if (!efi_virtmap_init()) {
+ pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
+ return -ENOMEM;
+ }
+
+ /* Set up runtime services function pointers */
+ efi_native_runtime_setup();
+ set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+
+ return 0;
+}
+early_initcall(riscv_enable_runtime_services);
+
+void efi_virtmap_load(void)
+{
+ preempt_disable();
+ switch_mm(current->active_mm, &efi_mm, NULL);
+}
+
+void efi_virtmap_unload(void)
+{
+ switch_mm(&efi_mm, current->active_mm, NULL);
+ preempt_enable();
+}