From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/firmware/efi/libstub/riscv-stub.c | 137 ++++++++++++++++++++++++++++++ 1 file changed, 137 insertions(+) create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c (limited to 'drivers/firmware/efi/libstub/riscv-stub.c') diff --git a/drivers/firmware/efi/libstub/riscv-stub.c b/drivers/firmware/efi/libstub/riscv-stub.c new file mode 100644 index 000000000..b450ebf95 --- /dev/null +++ b/drivers/firmware/efi/libstub/riscv-stub.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + */ + +#include +#include + +#include +#include +#include + +#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 long, unsigned long); + +static unsigned long hartid; + +static int get_boot_hartid_from_fdt(void) +{ + const void *fdt; + int chosen_node, len; + const void *prop; + + fdt = get_efi_config_table(DEVICE_TREE_GUID); + if (!fdt) + return -EINVAL; + + chosen_node = fdt_path_offset(fdt, "/chosen"); + if (chosen_node < 0) + return -EINVAL; + + prop = fdt_getprop((void *)fdt, chosen_node, "boot-hartid", &len); + if (!prop) + return -EINVAL; + + if (len == sizeof(u32)) + hartid = (unsigned long) fdt32_to_cpu(*(fdt32_t *)prop); + else if (len == sizeof(u64)) + hartid = (unsigned long) fdt64_to_cpu(__get_unaligned_t(fdt64_t, prop)); + else + return -EINVAL; + + return 0; +} + +static efi_status_t get_boot_hartid_from_efi(void) +{ + efi_guid_t boot_protocol_guid = RISCV_EFI_BOOT_PROTOCOL_GUID; + struct riscv_efi_boot_protocol *boot_protocol; + efi_status_t status; + + status = efi_bs_call(locate_protocol, &boot_protocol_guid, NULL, + (void **)&boot_protocol); + if (status != EFI_SUCCESS) + return status; + return efi_call_proto(boot_protocol, get_boot_hartid, &hartid); +} + +efi_status_t check_platform_features(void) +{ + efi_status_t status; + int ret; + + status = get_boot_hartid_from_efi(); + if (status != EFI_SUCCESS) { + ret = get_boot_hartid_from_fdt(); + if (ret) { + efi_err("Failed to get boot hartid!\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, + efi_handle_t image_handle) +{ + 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; +} -- cgit v1.2.3