Re: [PATCH 09/23] hw/ppc/mpc8544_guts: Populate POR PLL ratio status register

[Bernhard Beschow]

Am 23. September 2024 10:43:19 UTC schrieb BALATON Zoltan <balaton@eik.bme.hu>:
>On Mon, 23 Sep 2024, Bernhard Beschow wrote:
>> Populate this read-only register with some arbitrary values which avoids
>> U-Boot's get_clocks() to hang().
>
>Maybe this should be a property settable by the machine as each board may have 
>different values and it may need to use the correct value for the machine.

I actually considered this but went with the pragmatic solution to avoid 
over-engineering. In particular, I wanted to avoid further machine-specitic 
attributes in the machine class struct. Or do you expect a new e500 machine to 
be added? In that case I'd set above arbitrary values as default and expect a 
new machine to override these properties.

Best regards,
Bernhard

>
>Regards,
>BALATON Zoltan
>
>> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>> ---
>> hw/ppc/mpc8544_guts.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>> 
>> diff --git a/hw/ppc/mpc8544_guts.c b/hw/ppc/mpc8544_guts.c
>> index e3540b0281..6688fd44c3 100644
>> --- a/hw/ppc/mpc8544_guts.c
>> +++ b/hw/ppc/mpc8544_guts.c
>> @@ -29,6 +29,12 @@
>> #define MPC8544_GUTS_RSTCR_RESET      0x02
>> 
>> #define MPC8544_GUTS_ADDR_PORPLLSR    0x00
>> +REG32(GUTS_PORPLLSR, 0x00)
>> +    FIELD(GUTS_PORPLLSR, E500_1_RATIO, 16, 6)
>> +    FIELD(GUTS_PORPLLSR, E500_0_RATIO, 16, 6)
>> +    FIELD(GUTS_PORPLLSR, DDR_RATIO, 9, 5)
>> +    FIELD(GUTS_PORPLLSR, PLAT_RATIO, 1, 5)
>> +
>> #define MPC8544_GUTS_ADDR_PORBMSR     0x04
>> #define MPC8544_GUTS_ADDR_PORIMPSCR   0x08
>> #define MPC8544_GUTS_ADDR_PORDEVSR    0x0C
>> @@ -75,6 +81,12 @@ static uint64_t mpc8544_guts_read(void *opaque, hwaddr 
>> addr,
>> 
>>     addr &= MPC8544_GUTS_MMIO_SIZE - 1;
>>     switch (addr) {
>> +    case MPC8544_GUTS_ADDR_PORPLLSR:
>> +        value = FIELD_DP32(value, GUTS_PORPLLSR, E500_1_RATIO, 3); /* 3:2 */
>> +        value = FIELD_DP32(value, GUTS_PORPLLSR, E500_0_RATIO, 3); /* 3:2 */
>> +        value = FIELD_DP32(value, GUTS_PORPLLSR, DDR_RATIO, 6); /* 6:1 */
>> +        value = FIELD_DP32(value, GUTS_PORPLLSR, PLAT_RATIO, 4); /* 4:1 */
>> +        break;
>>     case MPC8544_GUTS_ADDR_PVR:
>>         value = env->spr[SPR_PVR];
>>         break;
>>