On Tue, 21 Feb 2023, BALATON Zoltan wrote:
On Tue, 21 Feb 2023, Paolo Bonzini wrote:
On 2/21/23 00:25, BALATON Zoltan wrote:
I think fundamentally you need to check for the condition
Size < mr->ops->impl.min_access_size in memory_region_dispatch_write
and then make a read, combine the result with
the value and make a write.
I neither know that part nor feel confident enough breaking such low level
stuff so I think setting the affected regions NATIVE_ENDIAN for now until
somebody takes care of this is safer and not likely to break anyting (or
if it does, much less widely and I'm more likely to be able to fix that
than your proposed changes). So I'd rather let you do that but I'd like
this fixed one way or another at last.
Sorry about not replying.
The case of impl.min_access_size < valid.min_access_size is not
supported in the memory core. Until that is done, the correct fix is to
fix acpi_pm_evt_ops to have impl.min_access_size == 1, something like
this:
diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 6da275c599c6..96eb88fa7e27 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -429,20 +429,35 @@ void acpi_pm1_evt_reset(ACPIREGS *ar)
static uint64_t acpi_pm_evt_read(void *opaque, hwaddr addr, unsigned width)
{
ACPIREGS *ar = opaque;
+ uint16_t val;
switch (addr) {
case 0:
- return acpi_pm1_evt_get_sts(ar);
+ val = acpi_pm1_evt_get_sts(ar);
case 2:
- return ar->pm1.evt.en;
+ val = ar->pm1.evt.en;
Some break; statements are missing here and above. This patch does not apply,
I had to apply it by hand to test it but it does not work. I don't have time
now to debug this. My patch works and don't see what else could it break. We
already have some devices set to native endian because of this so that could
be a usable workaround for now until you can fix it in memory layer.
You can reproduce this with the MorphOS demo iso on pegasos2 with the
original board firmware thath isn't free but availeble in an updater here:
http://web.archive.org/web/20071021223056/http://www.bplan-gmbh.de/up050404/up050404
and the script to get the rom image from it is here:
https://osdn.net/projects/qmiga/wiki/SubprojectPegasos2/attach/extract_rom_from_updater
the MorphOS iso is here:
https://www.morphos-team.net/morphos-3.17.iso
Then you can run it as:
qemu-system-ppc -M pegasos2 -bios pegasos2.rom -device ati-vga,romfile=""
-serial stdio -cdrom morphos-3.17.iso
at the firmware ok prompt type 'boot cd boot.img' then click OK button for
keyboard/language and once it booted press right mouse button on the top menu
To get that menu with Shut Down, first Quit the installer then again right
click or click on background first to get the menu of the Ambient desktop.
I also see an error from the firmware at the beginning:
Initializing KBD...00000012 FAILED.
when it's broken and it says Done without the hex number when it works.
(Two other FAILED messages about clock chip is normal as we don't emulate
that but all others should be green.)
bar and select Shutdown from the Ambient (first) menu. Click twice on Shutwon
button which should exit QEMU but does reboot instead without a fix. Can you
please come up with a working fix if my patch is not acceptable.
Thank you,
BALATON Zoltan
default:
return 0;
}
+
+ if (width == 1) {
+ int bitofs = (addr & 1) * 8;
+ val >>= bitofs;
+ }
+ return val;
}
static void acpi_pm_evt_write(void *opaque, hwaddr addr, uint64_t val,
unsigned width)
{
ACPIREGS *ar = opaque;
+ if (width == 1) {
+ int bitofs = (addr & 1) * 8;
+ uint16_t old_val = acpi_pm_evt_read(ar, addr, val & ~1);
+ uint16_t mask = 0xFF << bitofs;
+ val = (old_val & ~mask) | (val << bitofs);
+ addr &= ~1;
+ }
+
switch (addr) {
case 0:
acpi_pm1_evt_write_sts(ar, val);
@@ -458,7 +473,7 @@ static void acpi_pm_evt_write(void *opaque, hwaddr
addr, uint64_t val,
static const MemoryRegionOps acpi_pm_evt_ops = {
.read = acpi_pm_evt_read,
.write = acpi_pm_evt_write,
- .impl.min_access_size = 2,
+ .impl.min_access_size = 1,
.valid.min_access_size = 1,
.valid.max_access_size = 2,
.endianness = DEVICE_LITTLE_ENDIAN,
This assumes that the bus is little-endian, i.e. reading the byte at PM_EVT
returns
bits 0..7 and reading the byte at PM_EVT+1 returns bits 8..15.
If this is incorrect, endianness needs to be changed as well.
Paolo
