From 493250d616464e06d3100d6c89f72ac34814719c Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 20 Mar 2023 08:30:08 +1300 Subject: [PATCH] x86: Support booting a 64-bit kernel from 64-bit U-Boot Add the missing code to handle this. For a 64-bit kernel the entry address is 0x200 bytes after the normal entry. Rename the parameter to boot_linux_kernel() accordingly. Update the comments to indicate that these are addresses, not pointers. Signed-off-by: Simon Glass --- arch/x86/include/asm/bootm.h | 12 ++++++------ arch/x86/lib/bootm.c | 25 +++++++++++++++++-------- arch/x86/lib/zimage.c | 15 +++++++++++++-- 3 files changed, 36 insertions(+), 16 deletions(-) diff --git a/arch/x86/include/asm/bootm.h b/arch/x86/include/asm/bootm.h index 109f686f74..3b641783b9 100644 --- a/arch/x86/include/asm/bootm.h +++ b/arch/x86/include/asm/bootm.h @@ -14,14 +14,14 @@ void bootm_announce_and_cleanup(void); * This boots a kernel image, either 32-bit or 64-bit. It will also work with * a self-extracting kernel, if you set @image_64bit to false. * - * @setup_base: Pointer to the setup.bin information for the kernel - * @load_address: Pointer to the start of the kernel image - * @image_64bit: true if the image is a raw 64-bit kernel, false if it - * is raw 32-bit or any type of self-extracting kernel - * such as a bzImage. + * @setup_base: Address of the setup.bin information for the kernel + * @entry: Address of the kernel entry point + * @image_64bit: true if the image is a raw 64-bit kernel, or a kernel + * which supports booting in 64-bit mode; false if it is raw 32-bit or any type + * of self-extracting kernel such as a bzImage. * Return: -ve error code. This function does not return if the kernel was * booted successfully. */ -int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit); +int boot_linux_kernel(ulong setup_base, ulong entry, bool image_64bit); #endif diff --git a/arch/x86/lib/bootm.c b/arch/x86/lib/bootm.c index 873e2bc176..9beb376bb9 100644 --- a/arch/x86/lib/bootm.c +++ b/arch/x86/lib/bootm.c @@ -149,7 +149,7 @@ error: return 1; } -int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit) +int boot_linux_kernel(ulong setup_base, ulong entry, bool image_64bit) { bootm_announce_and_cleanup(); @@ -161,14 +161,23 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit) puts("Cannot boot 64-bit kernel on 32-bit machine\n"); return -EFAULT; } - /* At present 64-bit U-Boot does not support booting a + /* + * At present 64-bit U-Boot only supports booting a 64-bit * kernel. - * TODO(sjg@chromium.org): Support booting both 32-bit and - * 64-bit kernels from 64-bit U-Boot. + * + * TODO(sjg@chromium.org): Support booting 32-bit kernels from + * 64-bit U-Boot */ -#if !CONFIG_IS_ENABLED(X86_64) - return cpu_jump_to_64bit(setup_base, load_address); -#endif + if (CONFIG_IS_ENABLED(X86_64)) { + typedef void (*h_func)(ulong zero, ulong setup); + h_func func; + + /* jump to Linux with rdi=0, rsi=setup_base */ + func = (h_func)entry; + func(0, setup_base); + } else { + return cpu_jump_to_64bit(setup_base, entry); + } } else { /* * Set %ebx, %ebp, and %edi to 0, %esi to point to the @@ -190,7 +199,7 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit) "movl $0, %%ebp\n" "cli\n" "jmp *%[kernel_entry]\n" - :: [kernel_entry]"a"(load_address), + :: [kernel_entry]"a"(entry), [boot_params] "S"(setup_base), "b"(0), "D"(0) ); diff --git a/arch/x86/lib/zimage.c b/arch/x86/lib/zimage.c index a6d9151c32..e5ea5129c1 100644 --- a/arch/x86/lib/zimage.c +++ b/arch/x86/lib/zimage.c @@ -504,13 +504,24 @@ static int do_zboot_info(struct cmd_tbl *cmdtp, int flag, int argc, static int do_zboot_go(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { + struct boot_params *params = state.base_ptr; + struct setup_header *hdr = ¶ms->hdr; + bool image_64bit; + ulong entry; int ret; disable_interrupts(); + entry = state.load_address; + image_64bit = false; + if (IS_ENABLED(CONFIG_X86_RUN_64BIT) && + (hdr->xloadflags & XLF_KERNEL_64)) { + entry += 0x200; + image_64bit = true; + } + /* we assume that the kernel is in place */ - ret = boot_linux_kernel((ulong)state.base_ptr, state.load_address, - false); + ret = boot_linux_kernel((ulong)state.base_ptr, entry, image_64bit); printf("Kernel returned! (err=%d)\n", ret); return CMD_RET_FAILURE; -- 2.39.5