[U-Boot] [PATCH v4 1/8] x86: qemu: add fw_cfg support
Simon Glass
sjg at chromium.org
Thu Dec 31 06:07:51 CET 2015
Hi Miao,
On 30 December 2015 at 19:55, Miao Yan <yanmiaobest at gmail.com> wrote:
> 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 at gmail.com>
> ---
> Changes in v4:
> - cleanups
> - change 'fw load' to take second parameter for initrd load address
>
> arch/x86/cpu/qemu/Makefile | 2 +-
> arch/x86/cpu/qemu/fw_cfg.c | 268 +++++++++++++++++++++++++++++++++++++++++++++
> arch/x86/cpu/qemu/fw_cfg.h | 97 ++++++++++++++++
> arch/x86/cpu/qemu/qemu.c | 3 +
> 4 files changed, 369 insertions(+), 1 deletion(-)
> create mode 100644 arch/x86/cpu/qemu/fw_cfg.c
> create mode 100644 arch/x86/cpu/qemu/fw_cfg.h
Reviewed-by: Simon Glass <sjg at chromium.org>
But a few nits...
>
> 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
Can you put the new file first, so that the list is in alphabetical order?
> 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..9de8680
> --- /dev/null
> +++ b/arch/x86/cpu/qemu/fw_cfg.c
> @@ -0,0 +1,268 @@
> +/*
> + * (C) Copyright 2015 Miao Yan <yanmiaoebst at gmail.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <command.h>
> +#include <errno.h>
> +#include <malloc.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)
Function comment - what does this do?
> +{
> + uint32_t i = 0;
> + uint8_t *data = address;
> +
> + /*
> + * writting FW_CFG_INVALID will cause
> + * read operation to resume at
> + * last offset, otherwise read will
> + * start at offset 0
Please can you format comments to 75 columns or thereabout?
> + */
> +
> + 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 size, void *address)
> +{
> + struct fw_cfg_dma_access dma;
> +
> + dma.length = cpu_to_be32(size);
> + dma.address = cpu_to_be64((uintptr_t)address);
> + dma.control = cpu_to_be32(FW_CFG_DMA_READ);
> +
> + /*
> + * writting FW_CFG_INVALID will cause
> + * read operation to resume at
> + * last offset, otherwise read will
> + * start at offset 0
> + */
> +
> + if (entry != FW_CFG_INVALID)
> + dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
> +
> + barrier();
> +
> + debug("qemu_fwcfg_dma_read_entry: addr %p, length %u control 0x%x\n",
> + address, size, be32_to_cpu(dma.control));
> +
> + outl(cpu_to_be32((uint32_t)&dma), FW_DMA_PORT_HIGH);
> +
> + while (be32_to_cpu(dma.control) & ~FW_CFG_DMA_ERROR)
> + __asm__ __volatile__ ("pause");
> +}
> +
> +static bool 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 bool qemu_fwcfg_dma_present(void)
> +{
> + uint8_t dma_enabled;
> +
> + qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
> + if (dma_enabled & FW_CFG_DMA_ENABLED)
> + return true;
> +
> + return false;
> +}
> +
> +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);
> +}
> +
> +int qemu_fwcfg_online_cpus(void)
> +{
> + uint16_t nb_cpus;
> +
> + if (!fwcfg_present)
> + return 1;
-ENODEV
> +
> + qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
> +
> + return le16_to_cpu(nb_cpus);
> +}
> +
> +static int qemu_fwcfg_setup_kernel(void *load_addr, void *initrd_addr)
Function comment
> +{
> + char *data_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;
> + }
> +
> + data_addr = load_addr;
> + qemu_fwcfg_read_entry(FW_CFG_SETUP_DATA,
> + le32_to_cpu(setup_size), data_addr);
> + data_addr += le32_to_cpu(setup_size);
> +
> + qemu_fwcfg_read_entry(FW_CFG_KERNEL_DATA,
> + le32_to_cpu(kernel_size), data_addr);
> + data_addr += le32_to_cpu(kernel_size);
> +
> + data_addr = initrd_addr;
> + 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,
> + le32_to_cpu(initrd_size), data_addr);
> + data_addr += le32_to_cpu(initrd_size);
> + }
> +
> + qemu_fwcfg_read_entry(FW_CFG_CMDLINE_SIZE, 4, &cmdline_size);
> + if (cmdline_size) {
> + qemu_fwcfg_read_entry(FW_CFG_CMDLINE_DATA,
> + le32_to_cpu(cmdline_size), data_addr);
> + if (setenv("bootargs", data_addr) < 0)
> + printf("warning: unable to change bootargs\n");
> + }
> +
> + printf("loading kernel to address %p", load_addr);
> + if (initrd_size)
> + printf(" initrd %p, size 0x%x\n",
> + initrd_addr,
> + le32_to_cpu(initrd_size));
> + else
> + printf("\n");
> +
> + return 0;
> +}
> +
> +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 = qemu_fwcfg_present();
> + if (fwcfg_present)
> + fwcfg_dma_present = qemu_fwcfg_dma_present();
> +}
> +
> +static int qemu_fwcfg_do_list(cmd_tbl_t *cmdtp, int flag,
> + int argc, char * const argv[])
> +{
> + qemu_fwcfg_list_firmware();
Check return value and return CMD_RET_FAILURE if non-zero.
> +
> + return 0;
> +}
> +
> +static int qemu_fwcfg_do_cpus(cmd_tbl_t *cmdtp, int flag,
> + int argc, char * const argv[])
> +{
> + printf("%d cpu(s) online\n", qemu_fwcfg_online_cpus());
But qemu_fwcfg_online_cpus() can fail.
> +
> + return 0;
> +}
> +
> +static int qemu_fwcfg_do_load(cmd_tbl_t *cmdtp, int flag,
> + int argc, char * const argv[])
> +{
> + char *env;
> + void *load_addr;
> + void *initrd_addr;
> +
> + env = getenv("loadaddr");
> + load_addr = env ?
> + (void *)simple_strtoul(env, NULL, 16) :
> + (void *)CONFIG_LOADADDR;
> +
> + env = getenv("ramdiskaddr");
> + initrd_addr = env ?
> + (void *)simple_strtoul(env, NULL, 16) :
> + (void *)CONFIG_RAMDISK_ADDR;
> +
> + if (argc == 2) {
> + load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
> + initrd_addr = (void *)simple_strtoul(argv[1], NULL, 16);
> + } else if (argc == 1) {
> + load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
> + }
> +
> + return qemu_fwcfg_setup_kernel(load_addr, initrd_addr);
> +}
> +
> +static cmd_tbl_t fwcfg_commands[] = {
> + U_BOOT_CMD_MKENT(list, 0, 1, qemu_fwcfg_do_list, "", ""),
> + U_BOOT_CMD_MKENT(cpus, 0, 1, qemu_fwcfg_do_cpus, "", ""),
> + U_BOOT_CMD_MKENT(load, 2, 1, qemu_fwcfg_do_load, "", ""),
> +};
> +
> +static int do_qemu_fw(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> +{
> + int ret;
> + cmd_tbl_t *fwcfg_cmd;
> +
> + if (!fwcfg_present) {
> + printf("QEMU fw_cfg interface not found\n");
> + return CMD_RET_USAGE;
> + }
> +
> + fwcfg_cmd = find_cmd_tbl(argv[1], fwcfg_commands,
> + ARRAY_SIZE(fwcfg_commands));
> + argc -= 2;
> + argv += 2;
> + if (!fwcfg_cmd || argc > fwcfg_cmd->maxargs)
> + return CMD_RET_USAGE;
> +
> + ret = fwcfg_cmd->cmd(fwcfg_cmd, flag, argc, argv);
> +
> + return cmd_process_error(fwcfg_cmd, ret);
> +}
> +
> +U_BOOT_CMD(
> + fw, 4, 1, do_qemu_fw,
I worry that 'fw' is too generic. Perhaps qfw would be better?
> + "QEMU firmware interface",
> + "<command>\n"
> + " - list : print firmware(s) currently loaded\n"
> + " - cpus : print online cpu number\n"
print number of online CPUs
> + " - load <kernel addr> <initrd addr> : load kernel and initrd (if any), 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..03ac27d
> --- /dev/null
> +++ b/arch/x86/cpu/qemu/fw_cfg.h
> @@ -0,0 +1,97 @@
> +/*
> + * (C) Copyright 2015 Miao Yan <yanmiaobest at gmail.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#ifndef __FW_CFG__
> +#define __FW_CFG__
> +
> +#define FW_CONTROL_PORT 0x510
> +#define FW_DATA_PORT 0x511
> +#define FW_DMA_PORT_LOW 0x514
> +#define FW_DMA_PORT_HIGH 0x518
> +
> +enum qemu_fwcfg_items {
> + FW_CFG_SIGNATURE = 0x00,
> + FW_CFG_ID = 0x01,
> + FW_CFG_UUID = 0x02,
> + FW_CFG_RAM_SIZE = 0x03,
> + FW_CFG_NOGRAPHIC = 0x04,
> + FW_CFG_NB_CPUS = 0x05,
> + FW_CFG_MACHINE_ID = 0x06,
> + FW_CFG_KERNEL_ADDR = 0x07,
> + FW_CFG_KERNEL_SIZE = 0x08,
> + FW_CFG_KERNEL_CMDLINE = 0x09,
> + FW_CFG_INITRD_ADDR = 0x0a,
> + FW_CFG_INITRD_SIZE = 0x0b,
> + FW_CFG_BOOT_DEVICE = 0x0c,
> + FW_CFG_NUMA = 0x0d,
> + FW_CFG_BOOT_MENU = 0x0e,
> + FW_CFG_MAX_CPUS = 0x0f,
> + FW_CFG_KERNEL_ENTRY = 0x10,
> + FW_CFG_KERNEL_DATA = 0x11,
> + FW_CFG_INITRD_DATA = 0x12,
> + FW_CFG_CMDLINE_ADDR = 0x13,
> + FW_CFG_CMDLINE_SIZE = 0x14,
> + FW_CFG_CMDLINE_DATA = 0x15,
> + FW_CFG_SETUP_ADDR = 0x16,
> + FW_CFG_SETUP_SIZE = 0x17,
> + FW_CFG_SETUP_DATA = 0x18,
> + FW_CFG_FILE_DIR = 0x19,
> + FW_CFG_FILE_FIRST = 0x20,
> + FW_CFG_WRITE_CHANNEL = 0x4000,
> + FW_CFG_ARCH_LOCAL = 0x8000,
> + FW_CFG_INVALID = 0xffff,
> +};
> +
> +#define FW_CFG_FILE_SLOTS 0x10
> +#define FW_CFG_MAX_ENTRY (FW_CFG_FILE_FIRST+FW_CFG_FILE_SLOTS)
> +#define FW_CFG_ENTRY_MASK ~(FW_CFG_WRITE_CHANNEL | FW_CFG_ARCH_LOCAL)
> +
> +#define FW_CFG_MAX_FILE_PATH 56
> +
> +#define QEMU_FW_CFG_SIGNATURE (('Q' << 24) | ('E' << 16) | ('M' << 8) | 'U')
> +
> +#define FW_CFG_DMA_ERROR (1 << 0)
> +#define FW_CFG_DMA_READ (1 << 1)
> +#define FW_CFG_DMA_SKIP (1 << 2)
> +#define FW_CFG_DMA_SELECT (1 << 3)
> +
> +#define FW_CFG_DMA_ENABLED (1 << 1)
> +
> +struct fw_cfg_file {
> + __be32 size;
> + __be16 select;
> + __be16 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;
> +};
> +
> +/**
> + * Initialize QEMU fw_cfg interface
> + *
> + * @return: None
You can drop this line
> + */
> +
> +void qemu_fwcfg_init(void);
> +
> +/**
> + * Get system cpu number
> + *
> + * @return: cpu number in system
> + */
> +
> +int qemu_fwcfg_online_cpus(void);
> +
> +#endif
> diff --git a/arch/x86/cpu/qemu/qemu.c b/arch/x86/cpu/qemu/qemu.c
> index 1f93f72..d9ae066 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)
> --
> 1.9.1
>
Regards,
Simon
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