Re: [RFC] q800: fix I/O memory map

[Philippe Mathieu-Daudé]

On 10/31/19 11:03 AM, Laurent Vivier wrote:
> Linux kernel 5.4 will introduce a new memory map for SWIM device.
> (aee6bff1c325 ("m68k: mac: Revisit floppy disc controller base addresses"))
>
> Until this release all MMIO are mapped between 0x50f00000 and 0x50f40000,
> but it appears that for real hardware 0x50f00000 is not the base address:
> the MMIO region spans 0x50000000 through 0x60000000, and 0x50040000 through
> 0x54000000 is repeated images of 0x50000000 to 0x50040000.
>
> Fixed: 04e7ca8d0f ("hw/m68k: define Macintosh Quadra 800")
> Signed-off-by: Laurent Vivier <address@hidden>
> ---
>   hw/m68k/q800.c | 33 +++++++++++++++++++++++++--------
>   1 file changed, 25 insertions(+), 8 deletions(-)
>
> diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
> index 2b4842f8c6..8122e7c612 100644
> --- a/hw/m68k/q800.c
> +++ b/hw/m68k/q800.c
> @@ -60,14 +60,14 @@
>   #define MACH_MAC        3
>   #define Q800_MAC_CPU_ID 2
>   
> -#define VIA_BASE              0x50f00000
> -#define SONIC_PROM_BASE       0x50f08000
> -#define SONIC_BASE            0x50f0a000
> -#define SCC_BASE              0x50f0c020
> -#define ESP_BASE              0x50f10000
> -#define ESP_PDMA              0x50f10100
> -#define ASC_BASE              0x50F14000
> -#define SWIM_BASE             0x50F1E000
> +#define VIA_BASE              0x50000000
> +#define SONIC_PROM_BASE       0x50008000
> +#define SONIC_BASE            0x5000a000
> +#define SCC_BASE              0x5000c020
> +#define ESP_BASE              0x50010000
> +#define ESP_PDMA              0x50010100
> +#define ASC_BASE              0x50014000
> +#define SWIM_BASE             0x5001E000
>   #define NUBUS_SUPER_SLOT_BASE 0x60000000
>   #define NUBUS_SLOT_BASE       0xf0000000
>   
> @@ -135,6 +135,7 @@ static void q800_init(MachineState *machine)
>       int32_t initrd_size;
>       MemoryRegion *rom;
>       MemoryRegion *ram;
> +    int i;
>       ram_addr_t ram_size = machine->ram_size;
>       const char *kernel_filename = machine->kernel_filename;
>       const char *initrd_filename = machine->initrd_filename;
> @@ -163,10 +164,26 @@ static void q800_init(MachineState *machine)
>       cpu = M68K_CPU(cpu_create(machine->cpu_type));
>       qemu_register_reset(main_cpu_reset, cpu);
>   
> +    /* RAM */
>       ram = g_malloc(sizeof(*ram));
>       memory_region_init_ram(ram, NULL, "m68k_mac.ram", ram_size, &error_abort);
>       memory_region_add_subregion(get_system_memory(), 0, ram);
>   
> +    /*
> +     * Memory from VIA_BASE to VIA_BASE + 0x40000 is repeated
> +     * from VIA_BASE + 0x40000 to VIA_BASE + 0x4000000
> +     */

Maybe:

       const size_t via_aliases_count = (0x4000000 / 0x40000) - 1;
       MemoryRegion *via_alias = g_new(MemoryRegion, via_aliases_count);
       for (size_t i = 0; i < via_aliases_count; i++) {

           ...

           memory_region_add_subregion(get_system_memory(),
                                       VIA_BASE + (i + 1) * 0x40000,
                                       via_alias[i]);
           ...
       }

> +    for (i = 1; i < 256; i++) {
> +        MemoryRegion *io = g_malloc(sizeof(*io));
> +        char *name = g_strdup_printf("mac_m68k.io[%d]", i);
> +
> +        memory_region_init_alias(io, NULL, name, get_system_memory(),
> +                                 VIA_BASE, 0x40000);
> +        memory_region_add_subregion(get_system_memory(),
> +                                    VIA_BASE + i * 0x40000, io);
> +        g_free(name);
> +    }

I'm trying to get ride of this pattern, so I plan to refactor this later 
(and will use 256*KiB). Anyway not this patch problem.

Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> +
>       /* IRQ Glue */
>   
>       irq = g_new0(GLUEState, 1);