Re: [Qemu-devel] [PATCH v3 4/5] Enable fw_cfg DMA interface for ARM

[Laszlo Ersek <lersek@redhat.com>]

On 09/18/15 10:58, Marc Marí wrote:
> Enable the fw_cfg DMA interface for the ARM virt machine.
> 
> Based on Gerd Hoffman's initial implementation.
> 
> Signed-off-by: Marc Marí <markmb@redhat.com>
> ---
>  hw/arm/virt.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 3568107..47f4ad3 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -113,7 +113,7 @@ static const MemMapEntry a15memmap[] = {
>      [VIRT_GIC_V2M] =            { 0x08020000, 0x00001000 },
>      [VIRT_UART] =               { 0x09000000, 0x00001000 },
>      [VIRT_RTC] =                { 0x09010000, 0x00001000 },
> -    [VIRT_FW_CFG] =             { 0x09020000, 0x0000000a },
> +    [VIRT_FW_CFG] =             { 0x09020000, 0x00000014 },

Okay, Laszlo is the hateful reviewer. Sorry about that. I'm late, yes.

But: this says 0x00000014, ie 20 bytes in decimal. I don't think that's
correct; it should be 0x18 -- 24 bytes in decimal. From patch #2:
"DMA Address address:       Base + 16 (8 bytes)".

Thanks (and I'm sorry about being late!)
Laszlo

>      [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
>      /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */
>      [VIRT_PLATFORM_BUS] =       { 0x0c000000, 0x02000000 },
> @@ -651,13 +651,13 @@ static void create_flash(const VirtBoardInfo *vbi)
>      g_free(nodename);
>  }
>  
> -static void create_fw_cfg(const VirtBoardInfo *vbi)
> +static void create_fw_cfg(const VirtBoardInfo *vbi, AddressSpace *as)
>  {
>      hwaddr base = vbi->memmap[VIRT_FW_CFG].base;
>      hwaddr size = vbi->memmap[VIRT_FW_CFG].size;
>      char *nodename;
>  
> -    fw_cfg_init_mem_wide(base + 8, base, 8, 0, NULL);
> +    fw_cfg_init_mem_wide(base + 8, base, 8, base + 16, as);
>  
>      nodename = g_strdup_printf("/fw-cfg@%" PRIx64, base);
>      qemu_fdt_add_subnode(vbi->fdt, nodename);
> @@ -919,6 +919,7 @@ static void machvirt_init(MachineState *machine)
>  
>      create_fdt(vbi);
>  
> +
>      for (n = 0; n < smp_cpus; n++) {
>          ObjectClass *oc = cpu_class_by_name(TYPE_ARM_CPU, cpustr[0]);
>          CPUClass *cc = CPU_CLASS(oc);
> @@ -984,7 +985,7 @@ static void machvirt_init(MachineState *machine)
>       */
>      create_virtio_devices(vbi, pic);
>  
> -    create_fw_cfg(vbi);
> +    create_fw_cfg(vbi, &address_space_memory);
>      rom_set_fw(fw_cfg_find());
>  
>      guest_info->smp_cpus = smp_cpus;
>