[U-Boot] [PATCH v2 1/8] x86: qemu: add fw_cfg support
Miao Yan
yanmiaobest at gmail.com
Tue Dec 29 10:45:32 CET 2015
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 v2:
- rewrite command handling logic
- various cleanups
arch/x86/cpu/qemu/Makefile | 2 +-
arch/x86/cpu/qemu/fw_cfg.c | 241 +++++++++++++++++++++++++++++++++++++++++++++
arch/x86/cpu/qemu/fw_cfg.h | 97 ++++++++++++++++++
arch/x86/cpu/qemu/qemu.c | 3 +
4 files changed, 342 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..5f5cc68
--- /dev/null
+++ b/arch/x86/cpu/qemu/fw_cfg.c
@@ -0,0 +1,241 @@
+/*
+ * (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)
+{
+ 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 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);
+ 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 (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 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);
+}
+
+int 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 le16_to_cpu(nb_cpus);
+}
+
+static int qemu_fwcfg_setup_kernel(void *load_addr)
+{
+ 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);
+
+ 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);
+ qemu_fwcfg_read_entry(FW_CFG_CMDLINE_DATA,
+ le32_to_cpu(cmdline_size), data_addr);
+
+ printf("loading kernel to address %p", load_addr);
+ if (initrd_size)
+ printf(" initrd %p\n",
+ (char *)load_addr +
+ le32_to_cpu(setup_size) +
+ le32_to_cpu(kernel_size));
+ else
+ printf("\n");
+
+ return setenv("bootargs", data_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 = 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();
+
+ return 0;
+}
+
+static int qemu_fwcfg_do_cpus(cmd_tbl_t *cmdtp, int flag,
+ int argc, char * const argv[])
+{
+ printf("%u cpu(s) online\n", qemu_fwcfg_online_cpus());
+
+ return 0;
+}
+
+static int qemu_fwcfg_do_load(cmd_tbl_t *cmdtp, int flag,
+ int argc, char * const argv[])
+{
+ void *load_addr;
+
+ 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);
+}
+
+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, 1, 1, qemu_fwcfg_do_load, "", ""),
+};
+
+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 -= 3;
+ argv += 3;
+ 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, 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..f3d06d1
--- /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_FILE_SLOTS = 0x10,
+ FW_CFG_WRITE_CHANNEL = 0x4000,
+ FW_CFG_ARCH_LOCAL = 0x8000,
+ FW_CFG_INVALID = 0xffff,
+};
+
+#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 (0x1 << 0)
+#define FW_CFG_DMA_READ (0x1 << 1)
+#define FW_CFG_DMA_SKIP (0x1 << 2)
+#define FW_CFG_DMA_SELECT (0x1 << 3)
+
+#define FW_CFG_DMA_ENABLED 0x1
+
+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
+ *
+ * @retval: None
+ */
+
+void qemu_fwcfg_init(void);
+
+/**
+ * Get system cpu number
+ *
+ * @retval: 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
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