Re: [PATCH] hw/ppc/e500: Partial implementation of local access window registers

[Bernhard Beschow <shentey@gmail.com>]

Am 1. Februar 2025 14:55:15 UTC schrieb Bernhard Beschow <shentey@gmail.com>:
>
>
>Am 30. Januar 2025 12:45:58 UTC schrieb BALATON Zoltan <balaton@eik.bme.hu>:
>>On Wed, 15 Jan 2025, BALATON Zoltan wrote:
>>> This allows guests to set the CCSR base address. Also store and return
>>> values of the local access window registers but their functionality
>>> isn't implemented.
>>
>>Ping?
>
>I guess you're trying to boot a real firmware image from SD card? I've implemented that in my e500-fdt branch which I want to send as an RFC. I still need to clean it up. Once it's on the list we could make a plan how to turn it into a p10xx. Would that work for you?
>
>Best regards,
>Bernhard
>
>P.S. The last commit teaches you how to start a firmware from SD card.

Forgot to mention the link to the branch. Here it is: https://github.com/shentok/qemu/tree/e500-fdt

Best regards,
Bernhard

>
>>
>>> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
>>> ---
>>> hw/ppc/e500-ccsr.h |  4 +++
>>> hw/ppc/e500.c      | 79 ++++++++++++++++++++++++++++++++++++++++++++--
>>> 2 files changed, 80 insertions(+), 3 deletions(-)
>>> 
>>> diff --git a/hw/ppc/e500-ccsr.h b/hw/ppc/e500-ccsr.h
>>> index 249c17be3b..cfbf96e181 100644
>>> --- a/hw/ppc/e500-ccsr.h
>>> +++ b/hw/ppc/e500-ccsr.h
>>> @@ -4,12 +4,16 @@
>>> #include "hw/sysbus.h"
>>> #include "qom/object.h"
>>> 
>>> +#define NR_LAWS 12
>>> +
>>> struct PPCE500CCSRState {
>>>     /*< private >*/
>>>     SysBusDevice parent;
>>>     /*< public >*/
>>> 
>>>     MemoryRegion ccsr_space;
>>> +
>>> +    uint32_t law_regs[NR_LAWS * 2];
>>> };
>>> 
>>> #define TYPE_CCSR "e500-ccsr"
>>> diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
>>> index 64f8c766b4..376cb4cb37 100644
>>> --- a/hw/ppc/e500.c
>>> +++ b/hw/ppc/e500.c
>>> @@ -43,6 +43,7 @@
>>> #include "qemu/host-utils.h"
>>> #include "qemu/option.h"
>>> #include "hw/pci-host/ppce500.h"
>>> +#include "qemu/log.h"
>>> #include "qemu/error-report.h"
>>> #include "hw/platform-bus.h"
>>> #include "hw/net/fsl_etsec/etsec.h"
>>> @@ -1331,11 +1332,83 @@ void ppce500_init(MachineState *machine)
>>>     boot_info->dt_size = dt_size;
>>> }
>>> 
>>> +static int law_idx(hwaddr addr)
>>> +{
>>> +    int idx;
>>> +
>>> +    addr -= 0xc08;
>>> +    idx = 2 * ((addr >> 5) & 0xf);
>>> +    if (addr & 8) {
>>> +        idx++;
>>> +    }
>>> +    assert(idx < 2 * NR_LAWS);
>>> +    return idx;
>>> +}
>>> +
>>> +static uint64_t law_read(void *opaque, hwaddr addr, unsigned size)
>>> +{
>>> +    PPCE500CCSRState *s = opaque;
>>> +    uint64_t val = 0;
>>> +
>>> +    switch (addr) {
>>> +    case 0:
>>> +        val = s->ccsr_space.addr >> 12;
>>> +        break;
>>> +    case 0xc08 ... 0xd70:
>>> +        val = s->law_regs[law_idx(addr)];
>>> +        break;
>>> +    default:
>>> +        qemu_log_mask(LOG_GUEST_ERROR, "Invalid local access register read"
>>> +                      "0x%" HWADDR_PRIx "\n", addr);
>>> +    }
>>> +    return val;
>>> +}
>>> +
>>> +static void law_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
>>> +{
>>> +    PPCE500CCSRState *s = opaque;
>>> +
>>> +    switch (addr) {
>>> +    case 0:
>>> +        val &= 0xffff00;
>>> +        memory_region_set_address(&s->ccsr_space, val << 12);
>>> +        break;
>>> +    case 0xc08 ... 0xd70:
>>> +    {
>>> +        int idx = law_idx(addr);
>>> +
>>> +        qemu_log_mask(LOG_UNIMP, "Unimplemented local access register write"
>>> +                      "0x%" HWADDR_PRIx " <- 0x%" PRIx64 "\n", addr, val);
>>> +        val &= (idx & 1) ? 0x80f0003f : 0xffffff;
>>> +        s->law_regs[idx] = val;
>>> +        break;
>>> +    }
>>> +    default:
>>> +        qemu_log_mask(LOG_GUEST_ERROR, "Invalid local access register write"
>>> +                      "0x%" HWADDR_PRIx "\n", addr);
>>> +    }
>>> +}
>>> +
>>> +static const MemoryRegionOps law_ops = {
>>> +    .read = law_read,
>>> +    .write = law_write,
>>> +    .endianness = DEVICE_BIG_ENDIAN,
>>> +    .valid = {
>>> +        .min_access_size = 4,
>>> +        .max_access_size = 4,
>>> +    },
>>> +};
>>> +
>>> static void e500_ccsr_initfn(Object *obj)
>>> {
>>> -    PPCE500CCSRState *ccsr = CCSR(obj);
>>> -    memory_region_init(&ccsr->ccsr_space, obj, "e500-ccsr",
>>> -                       MPC8544_CCSRBAR_SIZE);
>>> +    PPCE500CCSRState *s = CCSR(obj);
>>> +    MemoryRegion *mr;
>>> +
>>> +    memory_region_init(&s->ccsr_space, obj, "e500-ccsr", MPC8544_CCSRBAR_SIZE);
>>> +
>>> +    mr = g_new(MemoryRegion, 1);
>>> +    memory_region_init_io(mr, obj, &law_ops, s, "local-access", 4096);
>>> +    memory_region_add_subregion(&s->ccsr_space, 0, mr);
>>> }
>>> 
>>> static const TypeInfo e500_ccsr_info = {
>>>