hw/misc/grlib_ahb_apb_pnp: Support 8 and 16 bit accesses

In real hardware, the APB and AHB PNP data tables can be accessed
with byte and halfword reads as well as word reads.  Our
implementation currently only handles word reads.  Add support for
the 8 and 16 bit accesses.  Note that we only need to handle aligned
accesses -- unaligned accesses should continue to trap, as happens on
hardware.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1132
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Frederic Konrad <fkonrad@amd.com>
Message-Id: <20220802131925.3380923-1-peter.maydell@linaro.org>
Tested-by: Tomasz Martyniak <gitlab.com/tom4r>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

hw/misc/grlib_ahb_apb_pnp.c

@@ -136,7 +136,8 @@ static uint64_t grlib_ahb_pnp_read(void *opaque, hwaddr offset, unsigned size)
     uint32_t val;
 
     val = ahb_pnp->regs[offset >> 2];
-    trace_grlib_ahb_pnp_read(offset, val);
+    val = extract32(val, (4 - (offset & 3) - size) * 8, size * 8);
+    trace_grlib_ahb_pnp_read(offset, size, val);
 
     return val;
 }
@@ -152,7 +153,7 @@ static const MemoryRegionOps grlib_ahb_pnp_ops = {
     .write      = grlib_ahb_pnp_write,
     .endianness = DEVICE_BIG_ENDIAN,
     .impl = {
-        .min_access_size = 4,
+        .min_access_size = 1,
         .max_access_size = 4,
     },
 };
@@ -247,7 +248,8 @@ static uint64_t grlib_apb_pnp_read(void *opaque, hwaddr offset, unsigned size)
     uint32_t val;
 
     val = apb_pnp->regs[offset >> 2];
-    trace_grlib_apb_pnp_read(offset, val);
+    val = extract32(val, (4 - (offset & 3) - size) * 8, size * 8);
+    trace_grlib_apb_pnp_read(offset, size, val);
 
     return val;
 }
@@ -263,7 +265,7 @@ static const MemoryRegionOps grlib_apb_pnp_ops = {
     .write      = grlib_apb_pnp_write,
     .endianness = DEVICE_BIG_ENDIAN,
     .impl = {
-        .min_access_size = 4,
+        .min_access_size = 1,
         .max_access_size = 4,
     },
 };

hw/misc/trace-events

@@ -247,8 +247,8 @@ via1_adb_poll(uint8_t data, const char *vadbint, int status, int index, int size
 via1_auxmode(int mode) "setting auxmode to %d"
 
 # grlib_ahb_apb_pnp.c
-grlib_ahb_pnp_read(uint64_t addr, uint32_t value) "AHB PnP read addr:0x%03"PRIx64" data:0x%08x"
-grlib_apb_pnp_read(uint64_t addr, uint32_t value) "APB PnP read addr:0x%03"PRIx64" data:0x%08x"
+grlib_ahb_pnp_read(uint64_t addr, unsigned size, uint32_t value) "AHB PnP read addr:0x%03"PRIx64" size:%u data:0x%08x"
+grlib_apb_pnp_read(uint64_t addr, unsigned size, uint32_t value) "APB PnP read addr:0x%03"PRIx64" size:%u data:0x%08x"
 
 # led.c
 led_set_intensity(const char *color, const char *desc, uint8_t intensity_percent) "LED desc:'%s' color:%s intensity: %u%%"