Re: [Qemu-devel] [PATCH v4] hw/pc: Support system flash memory with -pflash parameter

[Anthony Liguori <anthony@codemonkey.ws>]

On 07/08/2011 02:37 PM, Jordan Justen wrote:
> If -pflash is specified and -bios is specified then pflash will
> be mapped just below the system rom using hw/pflash_cfi01.c.
>
> If -pflash is specified on the command line, but -bios is
> not specified, then 'bios.bin' will NOT be loaded, and
> instead the -pflash flash image will be mapped just below
> 4GB in place of the normal rom image.

This is way too tied to the pc platform to be this generic.

I think a better approach would be to default to having unit=0 of 
IF_PFLASH default to a read-only BDS that points to bios.bin.  -bios 
would just be a short cut to use a different file name but you should be 
able to override with -drive too.

And to really simplify things, you could add a readonly flag to -bios 
such that you could do:

-bios foo.img,readonly=off

Which is what I think you're looking for semantically.

Regards,

Anthony Liguori

>
> Signed-off-by: Jordan Justen<jordan.l.justen@intel.com>
> Reviewed-by: Aurelien Jarno<aurelien@aurel32.net>



> ---
>   default-configs/i386-softmmu.mak   |    1 +
>   default-configs/x86_64-softmmu.mak |    1 +
>   hw/pc.c                            |  161 +++++++++++++++++++++++++++---------
>   3 files changed, 125 insertions(+), 38 deletions(-)
>
> diff --git a/default-configs/i386-softmmu.mak b/default-configs/i386-softmmu.mak
> index 55589fa..8697cd4 100644
> --- a/default-configs/i386-softmmu.mak
> +++ b/default-configs/i386-softmmu.mak
> @@ -21,3 +21,4 @@ CONFIG_PIIX_PCI=y
>   CONFIG_SOUND=y
>   CONFIG_HPET=y
>   CONFIG_APPLESMC=y
> +CONFIG_PFLASH_CFI01=y
> diff --git a/default-configs/x86_64-softmmu.mak b/default-configs/x86_64-softmmu.mak
> index 8895028..eca9284 100644
> --- a/default-configs/x86_64-softmmu.mak
> +++ b/default-configs/x86_64-softmmu.mak
> @@ -21,3 +21,4 @@ CONFIG_PIIX_PCI=y
>   CONFIG_SOUND=y
>   CONFIG_HPET=y
>   CONFIG_APPLESMC=y
> +CONFIG_PFLASH_CFI01=y
> diff --git a/hw/pc.c b/hw/pc.c
> index a3e8539..e25354f 100644
> --- a/hw/pc.c
> +++ b/hw/pc.c
> @@ -41,6 +41,7 @@
>   #include "sysemu.h"
>   #include "blockdev.h"
>   #include "ui/qemu-spice.h"
> +#include "flash.h"
>
>   /* output Bochs bios info messages */
>   //#define DEBUG_BIOS
> @@ -957,70 +958,154 @@ void pc_cpus_init(const char *cpu_model)
>       }
>   }
>
> -void pc_memory_init(const char *kernel_filename,
> -                    const char *kernel_cmdline,
> -                    const char *initrd_filename,
> -                    ram_addr_t below_4g_mem_size,
> -                    ram_addr_t above_4g_mem_size)
> +static void pc_isa_bios_init(ram_addr_t ram_offset, int ram_size)
>   {
> -    char *filename;
> -    int ret, linux_boot, i;
> -    ram_addr_t ram_addr, bios_offset, option_rom_offset;
> -    int bios_size, isa_bios_size;
> -    void *fw_cfg;
> -
> -    linux_boot = (kernel_filename != NULL);
> +    int isa_bios_size;
>
> -    /* allocate RAM */
> -    ram_addr = qemu_ram_alloc(NULL, "pc.ram",
> -                              below_4g_mem_size + above_4g_mem_size);
> -    cpu_register_physical_memory(0, 0xa0000, ram_addr);
> -    cpu_register_physical_memory(0x100000,
> -                 below_4g_mem_size - 0x100000,
> -                 ram_addr + 0x100000);
> -    if (above_4g_mem_size>  0) {
> -        cpu_register_physical_memory(0x100000000ULL, above_4g_mem_size,
> -                                     ram_addr + below_4g_mem_size);
> +    /* map the last 128KB of the BIOS in ISA space */
> +    isa_bios_size = ram_size;
> +    if (isa_bios_size>  (128 * 1024)) {
> +        isa_bios_size = 128 * 1024;
>       }
> +    ram_offset = ram_offset + ram_size - isa_bios_size;
> +    cpu_register_physical_memory(0x100000 - isa_bios_size,
> +                                 isa_bios_size,
> +                                 ram_offset | IO_MEM_ROM);
> +}
> +
> +static int pc_system_rom_init(void)
> +{
> +    int ret;
> +    int bios_size;
> +    ram_addr_t bios_offset;
> +    char *filename;
>
>       /* BIOS load */
> -    if (bios_name == NULL)
> +    if (bios_name == NULL) {
>           bios_name = BIOS_FILENAME;
> +    }
>       filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
>       if (filename) {
>           bios_size = get_image_size(filename);
>       } else {
>           bios_size = -1;
>       }
> -    if (bios_size<= 0 ||
> -        (bios_size % 65536) != 0) {
> -        goto bios_error;
> +
> +    if (bios_size<= 0 || (bios_size % 65536) != 0) {
> +        ret = -1;
> +    } else {
> +        bios_offset = qemu_ram_alloc(NULL, "pc.bios", bios_size);
> +        ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
>       }
> -    bios_offset = qemu_ram_alloc(NULL, "pc.bios", bios_size);
> -    ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
> +
>       if (ret != 0) {
> -    bios_error:
>           fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
>           exit(1);
>       }
> +
>       if (filename) {
>           qemu_free(filename);
>       }
> -    /* map the last 128KB of the BIOS in ISA space */
> -    isa_bios_size = bios_size;
> -    if (isa_bios_size>  (128 * 1024))
> -        isa_bios_size = 128 * 1024;
> -    cpu_register_physical_memory(0x100000 - isa_bios_size,
> -                                 isa_bios_size,
> -                                 (bios_offset + bios_size - isa_bios_size) | IO_MEM_ROM);
>
> -    option_rom_offset = qemu_ram_alloc(NULL, "pc.rom", PC_ROM_SIZE);
> -    cpu_register_physical_memory(PC_ROM_MIN_VGA, PC_ROM_SIZE, option_rom_offset);
> +    pc_isa_bios_init(bios_offset, bios_size);
>
>       /* map all the bios at the top of memory */
>       cpu_register_physical_memory((uint32_t)(-bios_size),
>                                    bios_size, bios_offset | IO_MEM_ROM);
>
> +    return bios_size;
> +}
> +
> +static void pc_system_flash_init(DriveInfo *pflash_drv, int rom_size)
> +{
> +    BlockDriverState *bdrv;
> +    int64_t size;
> +    target_phys_addr_t phys_addr;
> +    ram_addr_t addr;
> +    int sector_bits, sector_size;
> +
> +    bdrv = NULL;
> +
> +    bdrv = pflash_drv->bdrv;
> +    size = bdrv_getlength(pflash_drv->bdrv);
> +    sector_bits = 12;
> +    sector_size = 1<<  sector_bits;
> +
> +    if ((size % sector_size) != 0) {
> +        fprintf(stderr,
> +                "qemu: -pflash size must be a multiple of 0x%x\n",
> +                sector_size);
> +        exit(1);
> +    }
> +
> +    phys_addr = 0x100000000ULL - rom_size - size;
> +    addr = qemu_ram_alloc(NULL, "system.flash", size);
> +    DPRINTF("flash addr: 0x%lx\n", (int64_t)phys_addr);
> +    pflash_cfi01_register(phys_addr, addr, bdrv,
> +                          sector_size, size>>  sector_bits,
> +                          4, 0x0000, 0x0000, 0x0000, 0x0000, 0);
> +
> +    if (rom_size == 0) {
> +        pc_isa_bios_init(addr, size);
> +    }
> +}
> +
> +static void pc_system_firmware_init(void)
> +{
> +    int flash_present, rom_present;
> +    int rom_size;
> +    DriveInfo *pflash_drv;
> +
> +    pflash_drv = drive_get(IF_PFLASH, 0, 0);
> +    flash_present = (pflash_drv != NULL);
> +
> +    /* Load rom if -bios is used or if -pflash is not used */
> +    rom_present = ((bios_name != NULL) || !flash_present);
> +
> +    /* If rom is present, then it is mapped just below 4GB */
> +    if (rom_present) {
> +        rom_size = pc_system_rom_init();
> +    } else {
> +        rom_size = 0;
> +    }
> +
> +    /* If flash is present, then it is mapped just below the rom, or
> +     * just below 4GB when rom is not present. */
> +    if (flash_present) {
> +        pc_system_flash_init(pflash_drv, rom_size);
> +    }
> +}
> +
> +void pc_memory_init(const char *kernel_filename,
> +                    const char *kernel_cmdline,
> +                    const char *initrd_filename,
> +                    ram_addr_t below_4g_mem_size,
> +                    ram_addr_t above_4g_mem_size)
> +{
> +    int linux_boot, i;
> +    ram_addr_t ram_addr, option_rom_offset;
> +    void *fw_cfg;
> +
> +    linux_boot = (kernel_filename != NULL);
> +
> +    /* allocate RAM */
> +    ram_addr = qemu_ram_alloc(NULL, "pc.ram",
> +                              below_4g_mem_size + above_4g_mem_size);
> +    cpu_register_physical_memory(0, 0xa0000, ram_addr);
> +    cpu_register_physical_memory(0x100000,
> +                 below_4g_mem_size - 0x100000,
> +                 ram_addr + 0x100000);
> +    if (above_4g_mem_size>  0) {
> +        cpu_register_physical_memory(0x100000000ULL, above_4g_mem_size,
> +                                     ram_addr + below_4g_mem_size);
> +    }
> +
> +    /* Initialize ROM or flash ranges for PC firmware */
> +    pc_system_firmware_init();
> +
> +    option_rom_offset = qemu_ram_alloc(NULL, "pc.rom", PC_ROM_SIZE);
> +    cpu_register_physical_memory(PC_ROM_MIN_VGA, PC_ROM_SIZE, option_rom_offset);
> +
>       fw_cfg = bochs_bios_init();
>       rom_set_fw(fw_cfg);
>