Am 6. Oktober 2024 17:12:16 UTC schrieb BALATON Zoltan <bala...@eik.bme.hu>:
>On Sat, 5 Oct 2024, Bernhard Beschow wrote:
>> The CCSR space is just a container which is meant to be covered by platform
>> device memory regions. However, QEMU only implements a subset of these
>> devices.
>> Add some logging to see which devices a guest attempts to access.
>>
>> Signed-off-by: Bernhard Beschow <shen...@gmail.com>
>> ---
>> hw/ppc/ppce500_ccsr.c | 32 +++++++++++++++++++++++++++++++-
>> hw/ppc/trace-events | 3 +++
>> 2 files changed, 34 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/ppc/ppce500_ccsr.c b/hw/ppc/ppce500_ccsr.c
>> index 5d0e1e0e89..6659560674 100644
>> --- a/hw/ppc/ppce500_ccsr.c
>> +++ b/hw/ppc/ppce500_ccsr.c
>> @@ -13,12 +13,42 @@
>>
>> #include "qemu/osdep.h"
>> #include "ppce500_ccsr.h"
>> +#include "qemu/log.h"
>> +#include "trace.h"
>> +
>> +static uint64_t ppce500_ccsr_io_read(void *opaque, hwaddr addr, unsigned
>> size)
>> +{
>> + uint64_t value = 0;
>> +
>> + trace_ppce500_ccsr_io_read(addr, value, size);
>> + qemu_log_mask(LOG_UNIMP,
>> + "%s: unimplemented [0x%" HWADDR_PRIx "] -> 0\n",
>> + __func__, addr);
>
>I'm not sure having both unimp log and traces is the best way. I thought unimp
>log with an unimplemented device area would be the simplest and least
>intrusive for the code but if you prefer traces then maybe we don't need unimp
>logs. But adding these otherwise empty functions (which won't get populated as
>subdevices have their own regions) still bothers me a bit but not enough to
>block this if others have no opinion on it.
>
>I also had this patch:
>https://patchew.org/QEMU/cover.1728232526.git.bala...@eik.bme.hu/
>which I first thought might help but that's about guest_errors not unimp logs
>so does not apply here. What other unimp logs get in the way here that makes
>traces a better choice?
I have some rough implementations of a few other device models with unimp
logging. Having a dedicated trace here allows to see which unoccupied CCSR
regions a guest pokes. The unimp logging here actually disturbs the above, so
I'd remove it here.
Best regards,
Bernhard
>
>Regards,
>BALATON Zoltan
>
>> +
>> + return value;
>> +}
>> +
>> +static void ppce500_ccsr_io_write(void *opaque, hwaddr addr, uint64_t value,
>> + unsigned size)
>> +{
>> + trace_ppce500_ccsr_io_write(addr, value, size);
>> + qemu_log_mask(LOG_UNIMP,
>> + "%s: unimplemented [0x%" HWADDR_PRIx "] <- 0x%" PRIx32
>> "\n",
>> + __func__, addr, (uint32_t)value);
>> +}
>> +
>> +static const MemoryRegionOps ppce500_ccsr_ops = {
>> + .read = ppce500_ccsr_io_read,
>> + .write = ppce500_ccsr_io_write,
>> + .endianness = DEVICE_NATIVE_ENDIAN,
>> +};
>>
>> static void ppce500_ccsr_init(Object *obj)
>> {
>> PPCE500CCSRState *s = CCSR(obj);
>>
>> - memory_region_init(&s->ccsr_space, obj, "e500-ccsr",
>> MPC85XX_CCSRBAR_SIZE);
>> + memory_region_init_io(&s->ccsr_space, obj, &ppce500_ccsr_ops, obj,
>> + "e500-ccsr", MPC85XX_CCSRBAR_SIZE);
>> sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->ccsr_space);
>> }
>>
>> diff --git a/hw/ppc/trace-events b/hw/ppc/trace-events
>> index 1f125ce841..ca4c231c9f 100644
>> --- a/hw/ppc/trace-events
>> +++ b/hw/ppc/trace-events
>> @@ -143,6 +143,9 @@ ppc_irq_cpu(const char *action) "%s"
>> ppc_dcr_read(uint32_t addr, uint32_t val) "DRCN[0x%x] -> 0x%x"
>> ppc_dcr_write(uint32_t addr, uint32_t val) "DRCN[0x%x] <- 0x%x"
>>
>> +ppce500_ccsr_io_read(uint32_t index, uint32_t val, uint8_t size) "[0x%"
>> PRIx32 "] -> 0x%08x (size: 0x%" PRIu8 ")"
>> +ppce500_ccsr_io_write(uint32_t index, uint32_t val, uint8_t size) "[0x%"
>> PRIx32 "] <- 0x%08x (size: 0x%" PRIu8 ")"
>> +
>> # prep_systemio.c
>> prep_systemio_read(uint32_t addr, uint32_t val) "read addr=0x%x val=0x%x"
>> prep_systemio_write(uint32_t addr, uint32_t val) "write addr=0x%x val=0x%x"
>>
