Re: [PATCH 03/21] hw: aspeed_scu: Add AST2600 support

[Cédric Le Goater]

On 20/09/2019 06:10, Andrew Jeffery wrote:
> 
> 
> On Thu, 19 Sep 2019, at 15:19, Cédric Le Goater wrote:
>> From: Joel Stanley <address@hidden>
>>
>> The SCU controller on the AST2600 SoC has extra registers. Increase
>> the number of regs of the model and introduce a new field in the class
>> to customize the MemoryRegion operations depending on the SoC model.
>>
>> Signed-off-by: Joel Stanley <address@hidden>
>> [clg: - improved commit log
>>       - changed vmstate version
>>       - reworked model integration into new objet class ]
>> Signed-off-by: Cédric Le Goater <address@hidden>
>> ---
>>  include/hw/misc/aspeed_scu.h |   7 +-
>>  hw/misc/aspeed_scu.c         | 190 +++++++++++++++++++++++++++++++++--
>>  2 files changed, 189 insertions(+), 8 deletions(-)
> 
> ...
> 
>> +static void aspeed_ast2600_scu_write(void *opaque, hwaddr offset, 
>> uint64_t data,
>> +                                     unsigned size)
>> +{
>> +    AspeedSCUState *s = ASPEED_SCU(opaque);
>> +    int reg = TO_REG(offset);
>> +
>> +    if (reg >= ASPEED_AST2600_SCU_NR_REGS) {
>> +        qemu_log_mask(LOG_GUEST_ERROR,
>> +                      "%s: Out-of-bounds write at offset 0x%" 
>> HWADDR_PRIx "\n",
>> +                      __func__, offset);
>> +        return;
>> +    }
>> +
>> +    if (reg > PROT_KEY && !s->regs[PROT_KEY]) {
>> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: SCU is locked!\n", 
>> __func__);
>> +    }
>> +
>> +    trace_aspeed_scu_write(offset, size, data);
>> +
>> +    switch (reg) {
>> +    case AST2600_PROT_KEY:
>> +        s->regs[reg] = (data == ASPEED_SCU_PROT_KEY) ? 1 : 0;
>> +        return;
>> +    case AST2600_HW_STRAP1:
>> +    case AST2600_HW_STRAP2:
>> +        if (s->regs[reg + 2]) {
>> +            return;
>> +        }
>> +        /* fall through */
>> +    case AST2600_SYS_RST_CTRL:
>> +    case AST2600_SYS_RST_CTRL2:
>> +        /* W1S (Write 1 to set) registers */
>> +        s->regs[reg] |= data;
>> +        return;
>> +    case AST2600_SYS_RST_CTRL_CLR:
>> +    case AST2600_SYS_RST_CTRL2_CLR:
>> +    case AST2600_HW_STRAP1_CLR:
>> +    case AST2600_HW_STRAP2_CLR:
>> +        /* W1C (Write 1 to clear) registers */
>> +        s->regs[reg] &= ~data;
> 
> This clear should respect the protection register for each strap case.

Joel,

You are the expert ! :) 

Thanks,

C.