From: "Gabriel L. Somlo" <somlo@cmu.edu>
To: qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, jordan.l.justen@intel.com,
kraxel@redhat.com, pbonzini@redhat.com, markmb@redhat.com,
lersek@redhat.com
Subject: [Qemu-devel] [PATCH v3 4/5] fw_cfg: add generic non-DMA read method
Date: Mon, 2 Nov 2015 19:35:44 -0500 [thread overview]
Message-ID: <1446510945-18477-5-git-send-email-somlo@cmu.edu> (raw)
In-Reply-To: <1446510945-18477-1-git-send-email-somlo@cmu.edu>
Introduce fw_cfg_data_read(), a generic read method which works
on all access widths (1 through 8 bytes, inclusive), and can be
used during both IOPort and MMIO read accesses.
To maintain legibility, only fw_cfg_data_mem_read() (the MMIO
data read method) is replaced by this patch. The new method
essentially unwinds the fw_cfg_data_mem_read() + fw_cfg_read()
combo, but without unnecessarily repeating all the validity
checks performed by the latter on each byte being read.
This patch also modifies the trace_fw_cfg_read prototype to
accept a 64-bit value argument, allowing it to work properly
with the new read method, but also remain backward compatible
with existing call sites.
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Marc Marí <markmb@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
---
hw/nvram/fw_cfg.c | 33 +++++++++++++++++++--------------
trace-events | 2 +-
2 files changed, 20 insertions(+), 15 deletions(-)
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index c2d3a0a..8aa980c 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -274,6 +274,24 @@ 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->entries[arch][s->cur_entry & FW_CFG_ENTRY_MASK];
+ uint64_t value = 0;
+
+ assert(size <= sizeof(value));
+ if (s->cur_entry != FW_CFG_INVALID && e->data) {
+ while (size-- && s->cur_offset < e->len) {
+ value = (value << 8) | e->data[s->cur_offset++];
+ }
+ }
+
+ 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);
@@ -290,19 +308,6 @@ 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)
{
@@ -483,7 +488,7 @@ 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 72136b9..5073040 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
--
2.4.3
next prev parent reply other threads:[~2015-11-03 0:35 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-03 0:35 [Qemu-devel] [PATCH v3 0/5] fw_cfg: spec update, misc. cleanup, optimize read Gabriel L. Somlo
2015-11-03 0:35 ` [Qemu-devel] [PATCH v3 1/5] fw_cfg: move internal function call docs to header file Gabriel L. Somlo
2015-11-03 0:35 ` [Qemu-devel] [PATCH v3 2/5] fw_cfg: amend callback behavior spec to once per select Gabriel L. Somlo
2015-11-03 9:51 ` Laszlo Ersek
2015-11-03 0:35 ` [Qemu-devel] [PATCH v3 3/5] fw_cfg: remove offset argument from callback prototype Gabriel L. Somlo
2015-11-03 0:35 ` Gabriel L. Somlo [this message]
2015-11-03 10:53 ` [Qemu-devel] [PATCH v3 4/5] fw_cfg: add generic non-DMA read method Laszlo Ersek
2015-11-03 17:55 ` Gabriel L. Somlo
2015-11-03 21:35 ` Laszlo Ersek
2015-11-03 21:44 ` Gabriel L. Somlo
2015-11-03 22:03 ` Gabriel L. Somlo
2015-11-04 13:01 ` Laszlo Ersek
2015-11-03 0:35 ` [Qemu-devel] [PATCH v3 5/5] fw_cfg: replace ioport data read with generic method Gabriel L. Somlo
2015-11-03 11:11 ` Laszlo Ersek
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