2010-03-21 00:14:53

by Larry Finger

[permalink] [raw]
Subject: [PATCH] ssb: Implement virtual SPROM on disk

Some recent BCM43XX devices lack an on-board SPROM. The pertinent data
from the SPROM could be included in the kernel; however, this presents
a problem in the generation of a unique, reproducible MAC address. The
solution has been to create a utility that generates a virtual SPROM
image with a random MAC address. This image is stored in the firmware
area, and loaded using the asyncronous firmware load facility.

Signed-off-by: Larry Finger <[email protected]>
---

Michael,

I think this patch eliminates the need for the fallback sprom code; however,
I have not touched that facility yet.

Larry
---

Index: wireless-testing/drivers/ssb/pci.c
===================================================================
--- wireless-testing.orig/drivers/ssb/pci.c
+++ wireless-testing/drivers/ssb/pci.c
@@ -19,6 +19,7 @@
#include <linux/ssb/ssb_regs.h>
#include <linux/pci.h>
#include <linux/delay.h>
+#include <linux/firmware.h>

#include "ssb_private.h"

@@ -613,6 +614,39 @@ static int sprom_extract(struct ssb_bus
return 0;
}

+static int ssb_get_vsprom(struct device *dev, u16 *buf, size_t size)
+{
+ /* Use the firmware load facility to get the disk image of an SPROM */
+ const struct firmware *blob;
+ int err;
+ int i;
+
+ err = request_firmware(&blob, "ssb/vsprom_image", dev);
+ if (err) {
+ printk(KERN_ERR "ssb: The BCM43XX device does not have an "
+ "SPROM built in, and the virtual SPROM file is not"
+ " available.\n");
+ printk(KERN_ERR "ssb: Please go to "
+ "http://wireless.kernel.org/en/users/Drivers/b43 "
+ "and download the utility to create the file.\n");
+ return err;
+ }
+ if (blob->size != size * 2) {
+ printk(KERN_ERR "ssb: The virtual SPROM file has the wrong"
+ " size\n");
+ return -ENOENT;
+ }
+ for (i = 0; i < size; i++)
+ buf[i] = blob->data[2 * i + 1] << 8 | blob->data[2 * i];
+ err = sprom_check_crc(buf, size);
+ if (err) {
+ printk(KERN_ERR "ssb: Invalid CRC for virtual SPROM\n");
+ return err;
+ }
+
+ return 0;
+}
+
static int ssb_pci_sprom_get(struct ssb_bus *bus,
struct ssb_sprom *sprom)
{
@@ -620,8 +654,18 @@ static int ssb_pci_sprom_get(struct ssb_
int err = -ENOMEM;
u16 *buf;

- if (!ssb_is_sprom_available(bus))
- return -ENODEV;
+ if (!ssb_is_sprom_available(bus)) {
+ buf = kcalloc(SSB_SPROMSIZE_WORDS_R4, sizeof(u16),
+ GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ bus->sprom_size = SSB_SPROMSIZE_WORDS_R4;
+ if (ssb_get_vsprom(&bus->host_pci->dev, buf, bus->sprom_size)) {
+ err = -ENODEV;
+ goto out_free;
+ }
+ goto extract;
+ }

buf = kcalloc(SSB_SPROMSIZE_WORDS_R123, sizeof(u16), GFP_KERNEL);
if (!buf)
@@ -653,6 +697,7 @@ static int ssb_pci_sprom_get(struct ssb_
" SPROM CRC (corrupt SPROM)\n");
}
}
+extract:
err = sprom_extract(bus, sprom, buf, bus->sprom_size);

out_free:


2010-03-21 09:40:36

by Michael Büsch

[permalink] [raw]
Subject: Re: [PATCH] ssb: Implement virtual SPROM on disk

On Sunday 21 March 2010 01:14:51 Larry Finger wrote:
> Some recent BCM43XX devices lack an on-board SPROM. The pertinent data
> from the SPROM could be included in the kernel; however, this presents
> a problem in the generation of a unique, reproducible MAC address. The
> solution has been to create a utility that generates a virtual SPROM
> image with a random MAC address. This image is stored in the firmware
> area, and loaded using the asyncronous firmware load facility.
>
> Signed-off-by: Larry Finger <[email protected]>
> ---
>
> Michael,
>
> I think this patch eliminates the need for the fallback sprom code; however,
> I have not touched that facility yet.
>
> Larry
> ---
>
> Index: wireless-testing/drivers/ssb/pci.c
> ===================================================================
> --- wireless-testing.orig/drivers/ssb/pci.c
> +++ wireless-testing/drivers/ssb/pci.c
> @@ -19,6 +19,7 @@
> #include <linux/ssb/ssb_regs.h>
> #include <linux/pci.h>
> #include <linux/delay.h>
> +#include <linux/firmware.h>
>
> #include "ssb_private.h"
>
> @@ -613,6 +614,39 @@ static int sprom_extract(struct ssb_bus
> return 0;
> }
>
> +static int ssb_get_vsprom(struct device *dev, u16 *buf, size_t size)
> +{
> + /* Use the firmware load facility to get the disk image of an SPROM */
> + const struct firmware *blob;
> + int err;
> + int i;
> +
> + err = request_firmware(&blob, "ssb/vsprom_image", dev);

Well, this has the problem every synchronous firmware fetching mechanism has:
bootup with builtin module.
I think it should be done asynchronously.

> + if (err) {
> + printk(KERN_ERR "ssb: The BCM43XX device does not have an "
> + "SPROM built in, and the virtual SPROM file is not"
> + " available.\n");
> + printk(KERN_ERR "ssb: Please go to "
> + "http://wireless.kernel.org/en/users/Drivers/b43 "
> + "and download the utility to create the file.\n");
> + return err;
> + }
> + if (blob->size != size * 2) {
> + printk(KERN_ERR "ssb: The virtual SPROM file has the wrong"
> + " size\n");
> + return -ENOENT;
> + }
> + for (i = 0; i < size; i++)
> + buf[i] = blob->data[2 * i + 1] << 8 | blob->data[2 * i];
> + err = sprom_check_crc(buf, size);
> + if (err) {
> + printk(KERN_ERR "ssb: Invalid CRC for virtual SPROM\n");
> + return err;
> + }
> +
> + return 0;
> +}
> +
> static int ssb_pci_sprom_get(struct ssb_bus *bus,
> struct ssb_sprom *sprom)
> {
> @@ -620,8 +654,18 @@ static int ssb_pci_sprom_get(struct ssb_
> int err = -ENOMEM;
> u16 *buf;
>
> - if (!ssb_is_sprom_available(bus))
> - return -ENODEV;
> + if (!ssb_is_sprom_available(bus)) {
> + buf = kcalloc(SSB_SPROMSIZE_WORDS_R4, sizeof(u16),
> + GFP_KERNEL);
> + if (!buf)
> + return -ENOMEM;
> + bus->sprom_size = SSB_SPROMSIZE_WORDS_R4;
> + if (ssb_get_vsprom(&bus->host_pci->dev, buf, bus->sprom_size)) {
> + err = -ENODEV;
> + goto out_free;
> + }
> + goto extract;
> + }
>
> buf = kcalloc(SSB_SPROMSIZE_WORDS_R123, sizeof(u16), GFP_KERNEL);
> if (!buf)
> @@ -653,6 +697,7 @@ static int ssb_pci_sprom_get(struct ssb_
> " SPROM CRC (corrupt SPROM)\n");
> }
> }
> +extract:
> err = sprom_extract(bus, sprom, buf, bus->sprom_size);
>
> out_free:
>
>

--
Greetings, Michael.