IOPort read access is limited to one byte at a time by
fw_cfg_comb_valid(). As such, fw_cfg_comb_read() may safely
ignore its size argument (which will always be 1), and simply
call its fw_cfg_read() helper function once, returning 8 bits
via the least significant byte of a 64-bit return value.
This patch replaces fw_cfg_comb_read() with the generic method
fw_cfg_data_read(), and removes the unused fw_cfg_read() helper.
When called with size = 1, fw_cfg_data_read() acts exactly like
fw_cfg_read(), performing the same set of sanity checks, and
executing the while loop at most once (subject to the current
read offset being within range).
Cc: Laszlo Ersek <ler...@redhat.com>
Cc: Gerd Hoffmann <kra...@redhat.com>
Cc: Marc Marí <mar...@redhat.com>
Signed-off-by: Gabriel Somlo <so...@cmu.edu>
---
hw/nvram/fw_cfg.c | 24 +-----------------------
1 file changed, 1 insertion(+), 23 deletions(-)
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 8aa980c..7d216f0 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -292,22 +292,6 @@ static uint64_t fw_cfg_data_read(void *opaque, hwaddr
addr, unsigned size)
return value;
}
-static uint8_t fw_cfg_read(FWCfgState *s)
-{
- int arch = !!(s->cur_entry & FW_CFG_ARCH_LOCAL);
- FWCfgEntry *e = &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
- uint8_t ret;
-
- if (s->cur_entry == FW_CFG_INVALID || !e->data || s->cur_offset >= e->len)
- ret = 0;
- else {
- ret = e->data[s->cur_offset++];
- }
-
- trace_fw_cfg_read(s, ret);
- return ret;
-}
-
static void fw_cfg_data_mem_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
@@ -456,12 +440,6 @@ static bool fw_cfg_ctl_mem_valid(void *opaque, hwaddr addr,
return is_write && size == 2;
}
-static uint64_t fw_cfg_comb_read(void *opaque, hwaddr addr,
- unsigned size)
-{
- return fw_cfg_read(opaque);
-}
-
static void fw_cfg_comb_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
@@ -499,7 +477,7 @@ static const MemoryRegionOps fw_cfg_data_mem_ops = {
};
static const MemoryRegionOps fw_cfg_comb_mem_ops = {
- .read = fw_cfg_comb_read,
+ .read = fw_cfg_data_read,
.write = fw_cfg_comb_write,
.endianness = DEVICE_LITTLE_ENDIAN,
.valid.accepts = fw_cfg_comb_valid,
--
2.4.3
