On 03/07/2021 15:19, Philippe Mathieu-Daudé wrote:
From: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
Commit 3fe9a838ec "dp8393x: Always use 32-bit accesses" assumed that all
accesses
to the registers were 32-bit but this is actually not the case. The access size
is
determined by the CPU instruction used and not the number of physical address
lines.
The big_endian workaround applied to the register read/writes was actually
caused
by forcing the access size to 32-bit when the guest OS was using a 16-bit
access.
Since the registers are 16-bit then we can simply set .impl.min_access to 2 and
then the memory API will automatically do the right thing for both 16-bit
accesses
used by Linux and 32-bit accesses used by the MacOS toolbox ROM.
The change should work, but the commit message above needs a slight tweak - maybe
something like this?
Since the registers are 16-bit then we can simply set both .impl.min_access and
.impl.max_access to 2 and then the memory API will automatically do the right thing
for both 16-bit accesses used by Linux and 32-bit accesses used by the MacOS toolbox ROM.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
Fixes: 3fe9a838ec ("dp8393x: Always use 32-bit accesses")
Tested-by: Finn Thain <fth...@linux-m68k.org>
Message-Id: <20210625065401.30170-9-mark.cave-ayl...@ilande.co.uk>
[PMD: dp8393x_ops.impl.max_access_size 4 -> 2]
Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
---
hw/net/dp8393x.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/hw/net/dp8393x.c b/hw/net/dp8393x.c
index 11810c9b600..d16ade2b198 100644
--- a/hw/net/dp8393x.c
+++ b/hw/net/dp8393x.c
@@ -602,15 +602,14 @@ static uint64_t dp8393x_read(void *opaque, hwaddr addr,
unsigned int size)
trace_dp8393x_read(reg, reg_names[reg], val, size);
- return s->big_endian ? val << 16 : val;
+ return val;
}
-static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
+static void dp8393x_write(void *opaque, hwaddr addr, uint64_t val,
unsigned int size)
{
dp8393xState *s = opaque;
int reg = addr >> s->it_shift;
- uint32_t val = s->big_endian ? data >> 16 : data;
trace_dp8393x_write(reg, reg_names[reg], val, size);
@@ -694,8 +693,8 @@ static void dp8393x_write(void *opaque, hwaddr addr, uint64_t data,
static const MemoryRegionOps dp8393x_ops = {
.read = dp8393x_read,
.write = dp8393x_write,
- .impl.min_access_size = 4,
- .impl.max_access_size = 4,
+ .impl.min_access_size = 2,
+ .impl.max_access_size = 2,
.endianness = DEVICE_NATIVE_ENDIAN,
};
ATB,
Mark.
