Re: [PATCH v2] q800: fix I/O memory map

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 11/2/19 10:42 PM, 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 <laurent@vivier.eu>
> ---
> 
> Notes:
>      v2: add some constant definitions
>          allocate a bloc of memory to stores all I/O MemoryRegion
> 
>   hw/m68k/q800.c | 40 ++++++++++++++++++++++++++++++++--------
>   1 file changed, 32 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
> index 2b4842f8c6..822bd13d36 100644
> --- a/hw/m68k/q800.c
> +++ b/hw/m68k/q800.c
> @@ -60,14 +60,19 @@
>   #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 IO_BASE               0x50000000
> +#define IO_SLICE              0x00040000
> +#define IO_SIZE               0x04000000
> +
> +#define VIA_BASE              (IO_BASE + 0x00000)

Good idea.

> +#define SONIC_PROM_BASE       (IO_BASE + 0x08000)
> +#define SONIC_BASE            (IO_BASE + 0x0a000)
> +#define SCC_BASE              (IO_BASE + 0x0c020)
> +#define ESP_BASE              (IO_BASE + 0x10000)
> +#define ESP_PDMA              (IO_BASE + 0x10100)
> +#define ASC_BASE              (IO_BASE + 0x14000)
> +#define SWIM_BASE             (IO_BASE + 0x1E000)
> +
>   #define NUBUS_SUPER_SLOT_BASE 0x60000000
>   #define NUBUS_SLOT_BASE       0xf0000000
>   
> @@ -135,6 +140,9 @@ static void q800_init(MachineState *machine)
>       int32_t initrd_size;
>       MemoryRegion *rom;
>       MemoryRegion *ram;
> +    MemoryRegion *io;
> +    const int io_slice_nb = (IO_SIZE / IO_SLICE) - 1;
> +    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 +171,26 @@ 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 IO_BASE to IO_BASE + IO_SLICE is repeated
> +     * from IO_BASE + IO_SLICE to IO_BASE + IO_SIZE
> +     */
> +    io = g_new(MemoryRegion, io_slice_nb);
> +    for (i = 0; i < io_slice_nb; i++) {
> +        char *name = g_strdup_printf("mac_m68k.io[%d]", i + 1);
> +
> +        memory_region_init_alias(io + i, NULL, name, get_system_memory(),

We usually use &io[i], anyway:
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> +                                 IO_BASE, IO_SLICE);
> +        memory_region_add_subregion(get_system_memory(),
> +                                    IO_BASE + (i + 1) * IO_SLICE, io + i);
> +        g_free(name);
> +    }
> +
>       /* IRQ Glue */
>   
>       irq = g_new0(GLUEState, 1);
>