On most embedded ath9k devices (like range extenders,
routers, accesspoints, ...) the calibration data is
stored in a MTD partitions named "ART", or "caldata"/
"calibration".
Since commit 4b361cfa8624 ("mtd: core: add OTP nvmem provider support"):
All MTD partitions are all automatically available through
the nvmem subsystem.
This feature - together with an nvmem cell definition either
in the platform data or via device-tree allows drivers to get
the data necessary for initializing the WIFI, without having
to wait around for the filesystem and userspace to do
the extractions.
Signed-off-by: Christian Lamparter <[email protected]>
---
drivers/net/wireless/ath/ath9k/eeprom.c | 12 +++++-
drivers/net/wireless/ath/ath9k/hw.h | 2 +
drivers/net/wireless/ath/ath9k/init.c | 56 +++++++++++++++++++++++++
3 files changed, 69 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath9k/eeprom.c b/drivers/net/wireless/ath/ath9k/eeprom.c
index c22d457dbc54..e6b3cd49ea18 100644
--- a/drivers/net/wireless/ath/ath9k/eeprom.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom.c
@@ -135,13 +135,23 @@ static bool ath9k_hw_nvram_read_firmware(const struct firmware *eeprom_blob,
offset, data);
}
+static bool ath9k_hw_nvram_read_nvmem(struct ath_hw *ah, off_t offset,
+ u16 *data)
+{
+ return ath9k_hw_nvram_read_array(ah->nvmem_blob,
+ ah->nvmem_blob_len / sizeof(u16),
+ offset, data);
+}
+
bool ath9k_hw_nvram_read(struct ath_hw *ah, u32 off, u16 *data)
{
struct ath_common *common = ath9k_hw_common(ah);
struct ath9k_platform_data *pdata = ah->dev->platform_data;
bool ret;
- if (ah->eeprom_blob)
+ if (ah->nvmem_blob)
+ ret = ath9k_hw_nvram_read_nvmem(ah, off, data);
+ else if (ah->eeprom_blob)
ret = ath9k_hw_nvram_read_firmware(ah->eeprom_blob, off, data);
else if (pdata && !pdata->use_eeprom)
ret = ath9k_hw_nvram_read_pdata(pdata, off, data);
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index b7b65b1c90e8..096a206f49ed 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -977,6 +977,8 @@ struct ath_hw {
bool disable_5ghz;
const struct firmware *eeprom_blob;
+ u16 *nvmem_blob; /* devres managed */
+ size_t nvmem_blob_len;
struct ath_dynack dynack;
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index e9a36dd7144f..1568730fc01e 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -22,6 +22,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_net.h>
+#include <linux/nvmem-consumer.h>
#include <linux/relay.h>
#include <linux/dmi.h>
#include <net/ieee80211_radiotap.h>
@@ -568,6 +569,57 @@ static void ath9k_eeprom_release(struct ath_softc *sc)
release_firmware(sc->sc_ah->eeprom_blob);
}
+static int ath9k_nvmem_request_eeprom(struct ath_softc *sc)
+{
+ struct ath_hw *ah = sc->sc_ah;
+ struct nvmem_cell *cell;
+ void *buf;
+ size_t len;
+ int err;
+
+ cell = devm_nvmem_cell_get(sc->dev, "calibration");
+ if (IS_ERR(cell)) {
+ err = PTR_ERR(cell);
+
+ /* nvmem cell might not be defined, or the nvmem
+ * subsystem isn't included. In this case, follow
+ * the established "just return 0;" convention of
+ * ath9k_init_platform to say:
+ * "All good. Nothing to see here. Please go on."
+ */
+ if (err == -ENOENT || err == -EOPNOTSUPP)
+ return 0;
+
+ return err;
+ }
+
+ buf = nvmem_cell_read(cell, &len);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ /* run basic sanity checks on the returned nvram cell length.
+ * That length has to be a multiple of a "u16" (i.e.: & 1).
+ * Furthermore, it has to be more than "let's say" 512 bytes
+ * but less than the maximum of AR9300_EEPROM_SIZE (16kb).
+ */
+ if ((len & 1) == 1 || len < 512 || len >= AR9300_EEPROM_SIZE) {
+ kfree(buf);
+ return -EINVAL;
+ }
+
+ /* devres manages the calibration values release on shutdown */
+ ah->nvmem_blob = (u16 *)devm_kmemdup(sc->dev, buf, len, GFP_KERNEL);
+ kfree(buf);
+ if (IS_ERR(ah->nvmem_blob))
+ return PTR_ERR(ah->nvmem_blob);
+
+ ah->nvmem_blob_len = len;
+ ah->ah_flags &= ~AH_USE_EEPROM;
+ ah->ah_flags |= AH_NO_EEP_SWAP;
+
+ return 0;
+}
+
static int ath9k_init_platform(struct ath_softc *sc)
{
struct ath9k_platform_data *pdata = sc->dev->platform_data;
@@ -704,6 +756,10 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
if (ret)
return ret;
+ ret = ath9k_nvmem_request_eeprom(sc);
+ if (ret)
+ return ret;
+
if (ath9k_led_active_high != -1)
ah->config.led_active_high = ath9k_led_active_high == 1;
--
2.33.0
extends the owl loader to fetch important pci initialization
values - which are stored together with the calibration data -
through the nvmem subsystem.
This allows for much faster WIFI/ath9k initializations on devices
that do not require to perform any post-processing (like XOR'ing/
reversal or unpacking)... than the current way through the
firmware_request which involves the filesystem/userspace.
Signed-off-by: Christian Lamparter <[email protected]>
---
.../wireless/ath/ath9k/ath9k_pci_owl_loader.c | 105 +++++++++++++-----
1 file changed, 76 insertions(+), 29 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c b/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c
index 56d1a7764b9f..708c8969b503 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c
+++ b/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c
@@ -19,9 +19,14 @@
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/ath9k_platform.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/workqueue.h>
struct owl_ctx {
+ struct pci_dev *pdev;
struct completion eeprom_load;
+ struct work_struct work;
+ struct nvmem_cell *cell;
};
#define EEPROM_FILENAME_LEN 100
@@ -42,6 +47,12 @@ static int ath9k_pci_fixup(struct pci_dev *pdev, const u16 *cal_data,
u32 bar0;
bool swap_needed = false;
+ /* also note that we are doing *u16 operations on the file */
+ if (cal_len > 4096 || cal_len < 0x200 || (cal_len & 1) == 1) {
+ dev_err(&pdev->dev, "eeprom has an invalid size.\n");
+ return -EINVAL;
+ }
+
if (*cal_data != AR5416_EEPROM_MAGIC) {
if (*cal_data != swab16(AR5416_EEPROM_MAGIC)) {
dev_err(&pdev->dev, "invalid calibration data\n");
@@ -99,38 +110,31 @@ static int ath9k_pci_fixup(struct pci_dev *pdev, const u16 *cal_data,
return 0;
}
-static void owl_fw_cb(const struct firmware *fw, void *context)
+static void owl_rescan(struct pci_dev *pdev)
{
- struct pci_dev *pdev = (struct pci_dev *)context;
- struct owl_ctx *ctx = (struct owl_ctx *)pci_get_drvdata(pdev);
- struct pci_bus *bus;
-
- complete(&ctx->eeprom_load);
-
- if (!fw) {
- dev_err(&pdev->dev, "no eeprom data received.\n");
- goto release;
- }
-
- /* also note that we are doing *u16 operations on the file */
- if (fw->size > 4096 || fw->size < 0x200 || (fw->size & 1) == 1) {
- dev_err(&pdev->dev, "eeprom file has an invalid size.\n");
- goto release;
- }
-
- if (ath9k_pci_fixup(pdev, (const u16 *)fw->data, fw->size))
- goto release;
+ struct pci_bus *bus = pdev->bus;
pci_lock_rescan_remove();
- bus = pdev->bus;
pci_stop_and_remove_bus_device(pdev);
/* the device should come back with the proper
* ProductId. But we have to initiate a rescan.
*/
pci_rescan_bus(bus);
pci_unlock_rescan_remove();
+}
+
+static void owl_fw_cb(const struct firmware *fw, void *context)
+{
+ struct owl_ctx *ctx = (struct owl_ctx *)context;
+
+ complete(&ctx->eeprom_load);
-release:
+ if (fw) {
+ ath9k_pci_fixup(ctx->pdev, (const u16 *)fw->data, fw->size);
+ owl_rescan(ctx->pdev);
+ } else {
+ dev_err(&ctx->pdev->dev, "no eeprom data received.\n");
+ }
release_firmware(fw);
}
@@ -152,6 +156,43 @@ static const char *owl_get_eeprom_name(struct pci_dev *pdev)
return eeprom_name;
}
+static void owl_nvmem_work(struct work_struct *work)
+{
+ struct owl_ctx *ctx = container_of(work, struct owl_ctx, work);
+ void *buf;
+ size_t len;
+
+ complete(&ctx->eeprom_load);
+
+ buf = nvmem_cell_read(ctx->cell, &len);
+ if (!IS_ERR(buf)) {
+ ath9k_pci_fixup(ctx->pdev, buf, len);
+ kfree(buf);
+ owl_rescan(ctx->pdev);
+ } else {
+ dev_err(&ctx->pdev->dev, "no nvmem data received.\n");
+ }
+}
+
+static int owl_nvmem_probe(struct owl_ctx *ctx)
+{
+ int err;
+
+ ctx->cell = devm_nvmem_cell_get(&ctx->pdev->dev, "calibration");
+ if (IS_ERR(ctx->cell)) {
+ err = PTR_ERR(ctx->cell);
+ if (err == -ENOENT || err == -EOPNOTSUPP)
+ return 1; /* not present, try firmware_request */
+
+ return err;
+ }
+
+ INIT_WORK(&ctx->work, owl_nvmem_work);
+ schedule_work(&ctx->work);
+
+ return 0;
+}
+
static int owl_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
@@ -164,21 +205,27 @@ static int owl_probe(struct pci_dev *pdev,
pcim_pin_device(pdev);
- eeprom_name = owl_get_eeprom_name(pdev);
- if (!eeprom_name) {
- dev_err(&pdev->dev, "no eeprom filename found.\n");
- return -ENODEV;
- }
-
ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
init_completion(&ctx->eeprom_load);
+ ctx->pdev = pdev;
pci_set_drvdata(pdev, ctx);
+
+ err = owl_nvmem_probe(ctx);
+ if (err <= 0)
+ return err;
+
+ eeprom_name = owl_get_eeprom_name(pdev);
+ if (!eeprom_name) {
+ dev_err(&pdev->dev, "no eeprom filename found.\n");
+ return -ENODEV;
+ }
+
err = request_firmware_nowait(THIS_MODULE, true, eeprom_name,
- &pdev->dev, GFP_KERNEL, pdev, owl_fw_cb);
+ &pdev->dev, GFP_KERNEL, ctx, owl_fw_cb);
if (err)
dev_err(&pdev->dev, "failed to request caldata (%d).\n", err);
--
2.33.0
Christian Lamparter <[email protected]> wrote:
> On most embedded ath9k devices (like range extenders,
> routers, accesspoints, ...) the calibration data is
> stored in a MTD partitions named "ART", or "caldata"/
> "calibration".
>
> Since commit 4b361cfa8624 ("mtd: core: add OTP nvmem provider support"):
> All MTD partitions are all automatically available through
> the nvmem subsystem.
>
> This feature - together with an nvmem cell definition either
> in the platform data or via device-tree allows drivers to get
> the data necessary for initializing the WIFI, without having
> to wait around for the filesystem and userspace to do
> the extractions.
>
> Signed-off-by: Christian Lamparter <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>
2 patches applied to ath-next branch of ath.git, thanks.
eb3a97a69be8 ath9k: fetch calibration data via nvmem subsystem
ef7bc2a76342 ath9k: owl-loader: fetch pci init values through nvmem
--
https://patchwork.kernel.org/project/linux-wireless/patch/f9b732b50a3453fadf3923cc75d365bae3505fe7.1630157099.git.chunkeey@gmail.com/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches