Re: [Qemu-devel] [PATCH] isapc: Shadow ISA BIOS by default

[Anthony Liguori <aliguori@us.ibm.com>]

Jan Kiszka <jan.kiszka@siemens.com> writes:

> On 2012-09-11 17:53, Jan Kiszka wrote:
>> Our one and only BIOS depends on a writable shadowed BIOS in the ISA
>> range. As we have no interface to control the write property, make that
>> region writable by default.
>> 
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>> ---
>> 
>> This unbreaks isapc for TCG, and keep it working for KVM once it starts
>> supporting read-only memslots.
>> 
>>  hw/pc_sysfw.c |   13 +++++++++----
>>  1 files changed, 9 insertions(+), 4 deletions(-)
>> 
>> diff --git a/hw/pc_sysfw.c b/hw/pc_sysfw.c
>> index b45f0ac..027d98a 100644
>> --- a/hw/pc_sysfw.c
>> +++ b/hw/pc_sysfw.c
>> @@ -136,6 +136,7 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory)
>>  {
>>      char *filename;
>>      MemoryRegion *bios, *isa_bios;
>> +    void *isa_bios_ptr;
>>      int bios_size, isa_bios_size;
>>      int ret;
>>  
>> @@ -167,19 +168,23 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory)
>>          g_free(filename);
>>      }
>>  
>> -    /* map the last 128KB of the BIOS in ISA space */
>> +    /* Shadow the last 128KB of the BIOS in ISA space as RAM -
>> +     * Seabios depends on this */
>>      isa_bios_size = bios_size;
>>      if (isa_bios_size > (128 * 1024)) {
>>          isa_bios_size = 128 * 1024;
>>      }
>>      isa_bios = g_malloc(sizeof(*isa_bios));
>> -    memory_region_init_alias(isa_bios, "isa-bios", bios,
>> -                             bios_size - isa_bios_size, isa_bios_size);
>> +    memory_region_init_ram(isa_bios, "isa-bios", isa_bios_size);
>> +    vmstate_register_ram_global(isa_bios);
>>      memory_region_add_subregion_overlap(rom_memory,
>>                                          0x100000 - isa_bios_size,
>>                                          isa_bios,
>>                                          1);
>> -    memory_region_set_readonly(isa_bios, true);
>> +
>> +    /* copy ISA rom image from top of the ROM */
>> +    isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
>> +    rom_copy(isa_bios_ptr, (uint32_t)(-isa_bios_size), isa_bios_size);
>>  
>>      /* map all the bios at the top of memory */
>>      memory_region_add_subregion(rom_memory,
>> 
>
> Ping. Or already queued?

I've got it queued now.  Thanks.

Regards,

Anthony Liguori

>
> Jan
>
> -- 
> Siemens AG, Corporate Technology, CT RTC ITP SDP-DE
> Corporate Competence Center Embedded Linux