Re: [Qemu-devel] [Patch v1 4/8] target_arm: Remove memory region init from armv7m_init

[Alistair Francis]

On Tue, Sep 16, 2014 at 1:20 AM, Peter Crosthwaite
<address@hidden> wrote:
> On Sun, Sep 14, 2014 at 6:18 PM, Alistair Francis <address@hidden> wrote:
>> This patch moves the memory region init code from the
>> armv7m_init function to the stellaris_init function
>>
>> Signed-off-by: Alistair Francis <address@hidden>
>> ---
>>  hw/arm/armv7m.c    | 15 +--------------
>>  hw/arm/stellaris.c | 23 +++++++++++++++++++----
>>  2 files changed, 20 insertions(+), 18 deletions(-)
>>
>> diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
>> index aedef13..5c1f7b3 100644
>> --- a/hw/arm/armv7m.c
>> +++ b/hw/arm/armv7m.c
>> @@ -163,7 +163,7 @@ static void armv7m_reset(void *opaque)
>>  }
>>
>>  /* Init CPU and memory for a v7-M based board.
>> -   flash_size and sram_size are in kb.
>> +   flash_size and sram_size are in bytes.
>>     Returns the NVIC array.  */
>>
>>  qemu_irq *armv7m_init(MemoryRegion *system_memory,
>> @@ -180,13 +180,8 @@ qemu_irq *armv7m_init(MemoryRegion *system_memory,
>>      uint64_t lowaddr;
>>      int i;
>>      int big_endian;
>> -    MemoryRegion *sram = g_new(MemoryRegion, 1);
>> -    MemoryRegion *flash = g_new(MemoryRegion, 1);
>>      MemoryRegion *hack = g_new(MemoryRegion, 1);
>>
>> -    flash_size *= 1024;
>> -    sram_size *= 1024;
>> -
>>      if (cpu_model == NULL) {
>>         cpu_model = "cortex-m3";
>>      }
>> @@ -209,14 +204,6 @@ qemu_irq *armv7m_init(MemoryRegion *system_memory,
>>      code_size = ram_size - sram_size;
>>  #endif
>>
>> -    /* Flash programming is done via the SCU, so pretend it is ROM.  */
>> -    memory_region_init_ram(flash, NULL, "armv7m.flash", flash_size);
>> -    vmstate_register_ram_global(flash);
>> -    memory_region_set_readonly(flash, true);
>> -    memory_region_add_subregion(system_memory, 0, flash);
>> -    memory_region_init_ram(sram, NULL, "armv7m.sram", sram_size);
>> -    vmstate_register_ram_global(sram);
>> -    memory_region_add_subregion(system_memory, 0x20000000, sram);
>>      armv7m_bitband_init();
>>
>>      nvic = qdev_create(NULL, "armv7m_nvic");
>> diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
>> index 64bd4b4..3c8e9d1 100644
>> --- a/hw/arm/stellaris.c
>> +++ b/hw/arm/stellaris.c
>> @@ -1220,10 +1220,25 @@ static void stellaris_init(const char 
>> *kernel_filename, const char *cpu_model,
>>      int i;
>>      int j;
>>
>> -    flash_size = ((board->dc0 & 0xffff) + 1) << 1;
>> -    sram_size = (board->dc0 >> 18) + 1;
>> -    pic = armv7m_init(get_system_memory(),
>> -                      flash_size, sram_size, kernel_filename, cpu_model);
>> +    MemoryRegion *sram = g_new(MemoryRegion, 1);
>> +    MemoryRegion *flash = g_new(MemoryRegion, 1);
>> +    MemoryRegion *system_memory = get_system_memory();
>> +
>> +    flash_size = (((board->dc0 & 0xffff) + 1) << 1) * 1024;
>> +    sram_size = ((board->dc0 >> 18) + 1) * 1024;
>> +
>> +    /* Flash programming is done via the SCU, so pretend it is ROM.  */
>> +    memory_region_init_ram(flash, NULL, "armv7m.flash", flash_size);
>
> You can give this a better name, such as "stellaris.flash" now that we
> are not in armv7m anymore.

Will fix

>
> Paolo, do you have any advice as to whether we should attempt to
> parent this MR to the machine or something or just stay NULL
> (considering we are in non-qdevified code?).
>
>> +    vmstate_register_ram_global(flash);
>> +    memory_region_set_readonly(flash, true);
>> +    memory_region_add_subregion(system_memory, 0, flash);
>> +
>> +    memory_region_init_ram(sram, NULL, "armv7m.sram", sram_size);
>
> Ditto.
>
>> +    vmstate_register_ram_global(sram);
>> +    memory_region_add_subregion(system_memory, 0x20000000, sram);
>> +
>> +    pic = armv7m_init(system_memory, flash_size, sram_size,
>> +                      kernel_filename, cpu_model);
>>
>
> Can you drop the flash_size and sram_size args to armv7m? They should
> be dead now.

Both are still required. The load_image_targphys() requires the flash size and
there is some code that uses sram_size, although it is constantly #if disabled.
I'm not sure why it's there, but it would have to be removed if the
sram_size is.
It's something to do with greater then 32MB of SRAM overwriting the
bitband area.

>
> Regards,
> Peter
>
>>      if (board->dc1 & (1 << 16)) {
>>          dev = sysbus_create_varargs(TYPE_STELLARIS_ADC, 0x40038000,
>> --
>> 1.9.1
>>
>>