diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index 046fa749a5..8f566f61c1 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -274,6 +274,36 @@ static int fw_cfg_select(FWCfgState *s, uint16_t key) return ret; } +static uint64_t fw_cfg_data_read(void *opaque, hwaddr addr, unsigned size) +{ + FWCfgState *s = opaque; + int arch = !!(s->cur_entry & FW_CFG_ARCH_LOCAL); + FWCfgEntry *e = (s->cur_entry == FW_CFG_INVALID) ? NULL : + &s->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK]; + uint64_t value = 0; + + assert(size > 0 && size <= sizeof(value)); + if (s->cur_entry != FW_CFG_INVALID && e->data && s->cur_offset < e->len) { + /* The least significant 'size' bytes of the return value are + * expected to contain a string preserving portion of the item + * data, padded with zeros on the right in case we run out early. + * In technical terms, we're composing the host-endian representation + * of the big endian interpretation of the fw_cfg string. + */ + do { + value = (value << 8) | e->data[s->cur_offset++]; + } while (--size && s->cur_offset < e->len); + /* If size is still not zero, we *did* run out early, so continue + * left-shifting, to add the appropriate number of padding zeros + * on the right. + */ + value <<= 8 * size; + } + + trace_fw_cfg_read(s, value); + return value; +} + static uint8_t fw_cfg_read(FWCfgState *s) { int arch = !!(s->cur_entry & FW_CFG_ARCH_LOCAL); @@ -291,19 +321,6 @@ static uint8_t fw_cfg_read(FWCfgState *s) return ret; } -static uint64_t fw_cfg_data_mem_read(void *opaque, hwaddr addr, - unsigned size) -{ - FWCfgState *s = opaque; - uint64_t value = 0; - unsigned i; - - for (i = 0; i < size; ++i) { - value = (value << 8) | fw_cfg_read(s); - } - return value; -} - static void fw_cfg_data_mem_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { @@ -485,7 +502,7 @@ static const MemoryRegionOps fw_cfg_ctl_mem_ops = { }; static const MemoryRegionOps fw_cfg_data_mem_ops = { - .read = fw_cfg_data_mem_read, + .read = fw_cfg_data_read, .write = fw_cfg_data_mem_write, .endianness = DEVICE_BIG_ENDIAN, .valid = { diff --git a/trace-events b/trace-events index 2fce98e762..7fc4d114c9 100644 --- a/trace-events +++ b/trace-events @@ -196,7 +196,7 @@ ecc_diag_mem_readb(uint64_t addr, uint32_t ret) "Read diagnostic %"PRId64"= %02x # hw/nvram/fw_cfg.c fw_cfg_select(void *s, uint16_t key, int ret) "%p key %d = %d" -fw_cfg_read(void *s, uint8_t ret) "%p = %d" +fw_cfg_read(void *s, uint64_t ret) "%p = %"PRIx64 fw_cfg_add_file(void *s, int index, char *name, size_t len) "%p #%d: %s (%zd bytes)" # hw/block/hd-geometry.c