On 3/11/2018 10:47 PM, Hans de Goede wrote:
Various models Asus laptops with a SDIO attached brcmfmac wifi chip, store
the nvram contents in a special EFI variable. This commit adds support for
getting nvram directly from this EFI variable, without the user needing to
manually copy it.
This makes Wifi / Bluetooth work out of the box on these devices instead of
requiring manual setup.
Note that at least on the Asus T200TA the nvram from the EFI variable
wrongly contains "ccode=ALL" which the firmware does not understand, the
code to fetch the nvram from the EFI variable will fix this up to:
"ccode=XV" which is the correct way to specify the worldwide broadcast
regime.
This has been tested on the following models: Asus T100CHI, Asus T100HA,
Asus T100TA and Asus T200TA
Hi Hans,
I like to have this as well, but .... (see below)
Tested-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Duh. I would expect anyone to have tested their patches although you can
not cover every system out there obviously :-p
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
.../broadcom/brcm80211/brcmfmac/firmware.c | 68 +++++++++++++++++++++-
1 file changed, 67 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
index 091b52979e03..cbac407ae132 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
@@ -14,6 +14,8 @@
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
+#include <linux/dmi.h>
+#include <linux/efi.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
@@ -446,6 +448,67 @@ struct brcmf_fw {
void *nvram_image, u32 nvram_len);
};
+#ifdef CONFIG_EFI
+static u8 *brcmf_fw_nvram_from_efi(size_t *data_len_ret)
+{
+ const u16 name[] = { 'n', 'v', 'r', 'a', 'm', 0 };
Isn't there some helper function to make this conversion to u16 array?
Hmm, maybe it is my itch to scratch later :-)
+ struct efivar_entry *nvram_efivar;
+ unsigned long data_len = 0;
+ u8 *data = NULL;
+ char *ccode;
+ int err;
+
+ /* So far only Asus devices store the nvram in an EFI var */
+ if (!dmi_name_in_vendors("ASUSTeK COMPUTER INC."))
+ return NULL;
Actually had a Sony device with nvram in EFI. Why not just drop this
optimization.
+ nvram_efivar = kzalloc(sizeof(*nvram_efivar), GFP_KERNEL);
+ if (!nvram_efivar)
+ return NULL;
+
+ memcpy(&nvram_efivar->var.VariableName, name, sizeof(name));
+ nvram_efivar->var.VendorGuid = EFI_GUID(0x74b00bd9, 0x805a, 0x4d61,
+ 0xb5, 0x1f, 0x43, 0x26,
+ 0x81, 0x23, 0xd1, 0x13);
+
+ err = efivar_entry_size(nvram_efivar, &data_len);
+ if (err)
+ goto fail;
+
+ data = kmalloc(data_len, GFP_KERNEL);
+ if (!data)
+ goto fail;
+
+ err = efivar_entry_get(nvram_efivar, NULL, &data_len, data);
+ if (err)
+ goto fail;
+
+ /* In some cases the EFI-var stored nvram contains "ccode=ALL" but
+ * the firmware does not understand "ALL" change this to "XV" which
+ * is the correct way to specify the "worldwide" compatible settings.
+ */
This is actually quite bad. The ALL ccode should never end up on the
market as it is intended for internal use only during bringup project
phase so these seems to be programmed wrong. Also simply selecting XV
instead is not correct. There is not just one worldwide domain in the
regulatory database of the firmware image.
+ ccode = strnstr((char *)data, "ccode=ALL", data_len);
+ if (ccode) {
+ ccode[6] = 'X';
+ ccode[7] = 'V';
+ ccode[8] = '\n';
+ }
+
+ brcmf_info("Using nvram EFI variable\n");
+
+ kfree(nvram_efivar);
+ *data_len_ret = data_len;
+ return data;
+
+fail:
+ kfree(data);
+ kfree(nvram_efivar);
+ return NULL;
+}
+#else
+static u8 *brcmf_fw_nvram_from_efi(size_t *data_len) { return NULL; }
+#endif
+
static void brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
{
struct brcmf_fw *fwctx = ctx;
@@ -462,6 +525,8 @@ static void brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
raw_nvram = false;
} else {
data = bcm47xx_nvram_get_contents(&data_len);
+ if (!data)
+ data = brcmf_fw_nvram_from_efi(&data_len);
if (!data && !(fwctx->flags & BRCMF_FW_REQ_NV_OPTIONAL))
goto fail;
raw_nvram = true;
@@ -472,7 +537,8 @@ static void brcmf_fw_request_nvram_done(const struct firmware *fw, void *ctx)
fwctx->domain_nr, fwctx->bus_nr);
if (raw_nvram)
- bcm47xx_nvram_release_contents(data);
+ kvfree(data); /* vfree for bcm47xx case / kfree for efi case */
While this clearly works I can not say I like this. If you want to do it
this way, please submit a patch to remove
bcm47xx_nvram_release_contents() as it is no longer needed since we now
have kvfree(). From maintainance perspective also drop the postfix
comment. We just might end up doing vmalloc in efi case at some point
and this would likely be forgotten.
Regards,
Arend
