The QEMU fw_cfg interface allows the guest to retrieve various data information from QEMU. For example, APCI/SMBios tables, number of online cpus, kernel data and command line, etc.
This patch adds support for QEMU fw_cfg interface.
Signed-off-by: Miao Yan yanmiaobest@gmail.com --- arch/x86/cpu/qemu/Makefile | 2 +- arch/x86/cpu/qemu/fw_cfg.c | 215 +++++++++++++++++++++++++++++++++++++++++++++ arch/x86/cpu/qemu/fw_cfg.h | 84 ++++++++++++++++++ arch/x86/cpu/qemu/qemu.c | 3 + 4 files changed, 303 insertions(+), 1 deletion(-) create mode 100644 arch/x86/cpu/qemu/fw_cfg.c create mode 100644 arch/x86/cpu/qemu/fw_cfg.h
diff --git a/arch/x86/cpu/qemu/Makefile b/arch/x86/cpu/qemu/Makefile index 3f3958a..ad424ec 100644 --- a/arch/x86/cpu/qemu/Makefile +++ b/arch/x86/cpu/qemu/Makefile @@ -7,5 +7,5 @@ ifndef CONFIG_EFI_STUB obj-y += car.o dram.o endif -obj-y += qemu.o +obj-y += qemu.o fw_cfg.o obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi.o dsdt.o diff --git a/arch/x86/cpu/qemu/fw_cfg.c b/arch/x86/cpu/qemu/fw_cfg.c new file mode 100644 index 0000000..e7615d1 --- /dev/null +++ b/arch/x86/cpu/qemu/fw_cfg.c @@ -0,0 +1,215 @@ +/* + * (C) Copyright 2015 Miao Yan yanmiaoebst@gmail.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <command.h> +#include <environment.h> +#include <stdlib.h> +#include <malloc.h> +#include <errno.h> +#include <fs.h> +#include <asm/io.h> +#include "fw_cfg.h" + +static bool fwcfg_present; +static bool fwcfg_dma_present; + +static void qemu_fwcfg_read_entry_pio(uint16_t entry, + uint32_t size, void *address) +{ + uint32_t i = 0; + uint8_t *data = address; + + if (entry != FW_CFG_INVALID) + outw(entry, FW_CONTROL_PORT); + while (size--) + data[i++] = inb(FW_DATA_PORT); +} + +static void qemu_fwcfg_read_entry_dma(uint16_t entry, + uint32_t length, void *address) +{ + struct fw_cfg_dma_access dma; + + debug("qemu_fwcfg_dma_read_entry: addr %p, length %u control 0x%x\n", + address, length, dma.control); + + dma.length = cpu_to_be32(length); + dma.address = cpu_to_be64((uintptr_t)address); + dma.control = cpu_to_be32(FW_CFG_DMA_READ); + if (entry != FW_CFG_INVALID) + dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16)); + + barrier(); + + outl(cpu_to_be32((uint32_t)&dma), FW_DMA_PORT + 4); + + while (dma.control & ~FW_CFG_DMA_ERROR) + __asm__ __volatile__ ("rep;nop"); +} + +static int qemu_fwcfg_present(void) +{ + uint32_t qemu; + + qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu); + return be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE; +} + +static int qemu_fwcfg_dma_present(void) +{ + uint8_t dma_enabled; + uint32_t qemu; + + qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled); + if (dma_enabled & 0x1) { + qemu = inl(FW_DMA_PORT); + if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE) + return 1; + } + return 0; +} + +static void qemu_fwcfg_read_entry(uint16_t entry, + uint32_t length, void *address) +{ + if (fwcfg_dma_present) + qemu_fwcfg_read_entry_dma(entry, length, address); + else + qemu_fwcfg_read_entry_pio(entry, length, address); +} + +uint16_t qemu_fwcfg_online_cpus(void) +{ + uint16_t nb_cpus; + if (!fwcfg_present) + return 1; + + qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus); + return nb_cpus; +} + +static int qemu_fwcfg_setup_kernel(void *load_addr) +{ + char *cmd_addr; + uint32_t setup_size, kernel_size, cmdline_size, initrd_size; + + qemu_fwcfg_read_entry(FW_CFG_SETUP_SIZE, 4, &setup_size); + qemu_fwcfg_read_entry(FW_CFG_KERNEL_SIZE, 4, &kernel_size); + + if (setup_size == 0 || kernel_size == 0) { + printf("warning: no kernel available\n"); + return -1; + } + qemu_fwcfg_read_entry(FW_CFG_SETUP_DATA, setup_size, load_addr); + qemu_fwcfg_read_entry(FW_CFG_KERNEL_DATA, kernel_size, + (char *)load_addr + setup_size); + + qemu_fwcfg_read_entry(FW_CFG_INITRD_SIZE, 4, &initrd_size); + if (initrd_size == 0) { + printf("warning: no initrd available\n"); + } else { + qemu_fwcfg_read_entry(FW_CFG_INITRD_DATA, initrd_size, + (char *)load_addr + + setup_size + kernel_size); + } + + qemu_fwcfg_read_entry(FW_CFG_CMDLINE_SIZE, 4, &cmdline_size); + cmd_addr = (char *)load_addr + setup_size + kernel_size + initrd_size; + qemu_fwcfg_read_entry(FW_CFG_CMDLINE_DATA, cmdline_size, cmd_addr); + + printf("loading kernel to address %p", load_addr); + if (initrd_size) + printf(" initrd %p\n", + (char *)load_addr + setup_size + kernel_size); + else + printf("\n"); + + return setenv("bootargs", cmd_addr); +} + +static int qemu_fwcfg_list_firmware(void) +{ + int i; + uint32_t count; + struct fw_cfg_files *files; + + qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count); + if (!count) + return 0; + + count = be32_to_cpu(count); + files = malloc(count * sizeof(struct fw_cfg_file)); + if (!files) + return -ENOMEM; + + files->count = count; + qemu_fwcfg_read_entry(FW_CFG_INVALID, + count * sizeof(struct fw_cfg_file), + files->files); + + for (i = 0; i < files->count; i++) + printf("%-56s\n", files->files[i].name); + free(files); + return 0; +} + +void qemu_fwcfg_init(void) +{ + fwcfg_present = false; + fwcfg_dma_present = false; + + if (qemu_fwcfg_present()) { + fwcfg_present = true; + if (qemu_fwcfg_dma_present()) + fwcfg_dma_present = true; + } +} + +int do_qemu_fw(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + void *load_addr; + + if (!fwcfg_present) { + printf("no qemu fw_cfg found\n"); + return 0; + } + + if (!strncmp(argv[1], "list", 4)) { + qemu_fwcfg_list_firmware(); + return 0; + } else if (!strncmp(argv[1], "cpus", 4)) { + printf("%u\n", qemu_fwcfg_online_cpus()); + return 0; + } else if (!strncmp(argv[1], "load", 4)) { + if (argc == 3) { + load_addr = (void *)simple_strtoul(argv[2], NULL, 16); + } else { + load_addr = getenv("loadaddr"); + if (!load_addr) + load_addr = (void *)CONFIG_SYS_LOAD_ADDR; + else + load_addr = (void *)simple_strtoul(load_addr, + NULL, 16); + } + + return qemu_fwcfg_setup_kernel(load_addr); + + } else { + return -1; + } + + return 0; +} + +U_BOOT_CMD( + fw, 3, 1, do_qemu_fw, + "qemu firmware interface", + "<command>\n" + " - list : print firmware(s) currently loaded\n" + " - cpus : print online cpu number\n" + " - load <addr> : load kernel (if any) to address <addr>, and setup for zboot\n" +) diff --git a/arch/x86/cpu/qemu/fw_cfg.h b/arch/x86/cpu/qemu/fw_cfg.h new file mode 100644 index 0000000..66e0c8a --- /dev/null +++ b/arch/x86/cpu/qemu/fw_cfg.h @@ -0,0 +1,84 @@ +/* + * (C) Copyright 2015 Miao Yan yanmiaobest@gmail.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __FW_CFG__ +#define __FW_CFG__ + +#include <common.h> +#include <asm/io.h> + +#define FW_CONTROL_PORT 0x510 +#define FW_DATA_PORT 0x511 +#define FW_DMA_PORT 0x514 + +#define FW_CFG_SIGNATURE 0x00 +#define FW_CFG_ID 0x01 +#define FW_CFG_UUID 0x02 +#define FW_CFG_RAM_SIZE 0x03 +#define FW_CFG_NOGRAPHIC 0x04 +#define FW_CFG_NB_CPUS 0x05 +#define FW_CFG_MACHINE_ID 0x06 +#define FW_CFG_KERNEL_ADDR 0x07 +#define FW_CFG_KERNEL_SIZE 0x08 +#define FW_CFG_KERNEL_CMDLINE 0x09 +#define FW_CFG_INITRD_ADDR 0x0a +#define FW_CFG_INITRD_SIZE 0x0b +#define FW_CFG_BOOT_DEVICE 0x0c +#define FW_CFG_NUMA 0x0d +#define FW_CFG_BOOT_MENU 0x0e +#define FW_CFG_MAX_CPUS 0x0f +#define FW_CFG_KERNEL_ENTRY 0x10 +#define FW_CFG_KERNEL_DATA 0x11 +#define FW_CFG_INITRD_DATA 0x12 +#define FW_CFG_CMDLINE_ADDR 0x13 +#define FW_CFG_CMDLINE_SIZE 0x14 +#define FW_CFG_CMDLINE_DATA 0x15 +#define FW_CFG_SETUP_ADDR 0x16 +#define FW_CFG_SETUP_SIZE 0x17 +#define FW_CFG_SETUP_DATA 0x18 +#define FW_CFG_FILE_DIR 0x19 + +#define FW_CFG_FILE_FIRST 0x20 +#define FW_CFG_FILE_SLOTS 0x10 +#define FW_CFG_MAX_ENTRY (FW_CFG_FILE_FIRST+FW_CFG_FILE_SLOTS) + +#define FW_CFG_WRITE_CHANNEL 0x4000 +#define FW_CFG_ARCH_LOCAL 0x8000 +#define FW_CFG_ENTRY_MASK ~(FW_CFG_WRITE_CHANNEL | FW_CFG_ARCH_LOCAL) + +#define FW_CFG_INVALID 0xffff + +#define FW_CFG_MAX_FILE_PATH 56 + +#define QEMU_FW_CFG_SIGNATURE (('Q' << 24) | ('E' << 16) | ('M' << 8) | 'U') + +#define FW_CFG_DMA_ERROR (0x1) +#define FW_CFG_DMA_READ (0x2) +#define FW_CFG_DMA_SKIP (0x4) +#define FW_CFG_DMA_SELECT (0x8) + +struct fw_cfg_file { + uint32_t size; + uint16_t select; + uint16_t reserved; + char name[FW_CFG_MAX_FILE_PATH]; +}; + +struct fw_cfg_files { + __be32 count; + struct fw_cfg_file files[]; +}; + +struct fw_cfg_dma_access { + __be32 control; + __be32 length; + __be64 address; +}; + +void qemu_fwcfg_init(void); +uint16_t qemu_fwcfg_online_cpus(void); + +#endif diff --git a/arch/x86/cpu/qemu/qemu.c b/arch/x86/cpu/qemu/qemu.c index 84fb082..c0a79d2 100644 --- a/arch/x86/cpu/qemu/qemu.c +++ b/arch/x86/cpu/qemu/qemu.c @@ -11,6 +11,7 @@ #include <asm/processor.h> #include <asm/arch/device.h> #include <asm/arch/qemu.h> +#include "fw_cfg.h"
static bool i440fx;
@@ -57,6 +58,8 @@ static void qemu_chipset_init(void) x86_pci_write_config32(PCI_BDF(0, 0, 0), PCIEX_BAR, CONFIG_PCIE_ECAM_BASE | BAR_EN); } + + qemu_fwcfg_init(); }
int arch_cpu_init(void)