[PATCH] bcma: don't fail for bad SPROM CRC

[PATCH] bcma: don't fail for bad SPROM CRC

[Henrik Rydberg]

The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
chipsets unrecognized that were functional prior to the switch. In
particular, the current code bails out on recent Macbooks. This patch
simply ignores the outcome of the CRC check, with the argument that an
unrecognized SPROM should be treated similarly to a non-existing one.

Cc: Arend van Spriel <arend@broadcom.com>
Cc: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
Hi John,

It seems this patch may have gotten lost, at least I have not seen it
on any of the net/wireless parties. Arend, are you ok with the final
wording?

Thanks,
Henrik

 drivers/bcma/main.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c
index febbc0a..ec31f7d 100644
--- a/drivers/bcma/main.c
+++ b/drivers/bcma/main.c
@@ -169,10 +169,8 @@ int bcma_bus_register(struct bcma_bus *bus)
 	err = bcma_sprom_get(bus);
 	if (err == -ENOENT) {
 		pr_err("No SPROM available\n");
-	} else if (err) {
+	} else if (err)
 		pr_err("Failed to get SPROM: %d\n", err);
-		return -ENOENT;
-	}
 
 	/* Register found cores */
 	bcma_register_cores(bus);
-- 
1.7.9

Re: [PATCH] bcma: don't fail for bad SPROM CRC

[Arend van Spriel]

On 02/06/2012 02:26 PM, Henrik Rydberg wrote:
> The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
> chipsets unrecognized that were functional prior to the switch. In
> particular, the current code bails out on recent Macbooks. This patch
> simply ignores the outcome of the CRC check, with the argument that an
> unrecognized SPROM should be treated similarly to a non-existing one.

Suggestion:

The brcmsmac driver is now registered as a bcma device driver. Some
chipsets fail on SPROM CRC check in the bcma bus driver. This leaves the
chipset unrecognized and the bcma bus is not registered so that brcmsmac
is not probed. In particular, the current code .......

Gr. AvS

Re: [PATCH] bcma: don't fail for bad SPROM CRC

[Henrik Rydberg]

On Mon, Feb 06, 2012 at 02:34:08PM +0100, Arend van Spriel wrote:
> On 02/06/2012 02:26 PM, Henrik Rydberg wrote:
> > The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
> > chipsets unrecognized that were functional prior to the switch. In
> > particular, the current code bails out on recent Macbooks. This patch
> > simply ignores the outcome of the CRC check, with the argument that an
> > unrecognized SPROM should be treated similarly to a non-existing one.
> 
> Suggestion:
> 
> The brcmsmac driver is now registered as a bcma device driver. Some
> chipsets fail on SPROM CRC check in the bcma bus driver. This leaves the
> chipset unrecognized and the bcma bus is not registered so that brcmsmac
> is not probed. In particular, the current code .......

All fine with me. To avoid confusion, here is the patch again, with
the above inserted.

Thanks,
Henrik

---

From 57a4fbd1767b3c2e7c32d288b713e1b06e597bd6 Mon Sep 17 00:00:00 2001
From: Henrik Rydberg <rydberg@euromail.se>
Date: Tue, 31 Jan 2012 14:22:15 -0500
Subject: [PATCH] bcma: don't fail for bad SPROM CRC
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The brcmsmac driver is now registered as a bcma device driver. Some
chipsets fail on SPROM CRC check in the bcma bus driver. This leaves
the chipset unrecognized and the bcma bus is not registered so that
brcmsmac is not probed. In particular, the current code bails out on
recent Macbooks. This patch simply ignores the outcome of the CRC
check, with the argument that an unrecognized SPROM should be treated
similarly to a non-existing one.

Cc: Arend van Spriel <arend@broadcom.com>
Cc: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 drivers/bcma/main.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c
index febbc0a..ec31f7d 100644
--- a/drivers/bcma/main.c
+++ b/drivers/bcma/main.c
@@ -169,10 +169,8 @@ int bcma_bus_register(struct bcma_bus *bus)
 	err = bcma_sprom_get(bus);
 	if (err == -ENOENT) {
 		pr_err("No SPROM available\n");
-	} else if (err) {
+	} else if (err)
 		pr_err("Failed to get SPROM: %d\n", err);
-		return -ENOENT;
-	}
 
 	/* Register found cores */
 	bcma_register_cores(bus);
-- 
1.7.9

Re: [PATCH] bcma: don't fail for bad SPROM CRC

[Rafał Miłecki]

2012/2/6 Henrik Rydberg <rydberg@euromail.se>:
> The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
> chipsets unrecognized that were functional prior to the switch. In
> particular, the current code bails out on recent Macbooks. This patch
> simply ignores the outcome of the CRC check, with the argument that an
> unrecognized SPROM should be treated similarly to a non-existing one.

Have you maybe tried to look at the real solution?

-- 
Rafał

Re: [PATCH] bcma: don't fail for bad SPROM CRC

[Henrik Rydberg]

On Mon, Feb 06, 2012 at 06:08:51PM +0100, Rafał Miłecki wrote:
> 2012/2/6 Henrik Rydberg <rydberg@euromail.se>:
> > The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
> > chipsets unrecognized that were functional prior to the switch. In
> > particular, the current code bails out on recent Macbooks. This patch
> > simply ignores the outcome of the CRC check, with the argument that an
> > unrecognized SPROM should be treated similarly to a non-existing one.
> 
> Have you maybe tried to look at the real solution?

No, this is a pure regression fix.

Henrik

Re: [PATCH] bcma: don't fail for bad SPROM CRC

[Arend van Spriel]

On 02/06/2012 06:08 PM, Rafał Miłecki wrote:
> 2012/2/6 Henrik Rydberg <rydberg@euromail.se>:
>> The brcmsmac driver is now checking the bcma SPROM CRCs, leaving some
>> chipsets unrecognized that were functional prior to the switch. In
>> particular, the current code bails out on recent Macbooks. This patch
>> simply ignores the outcome of the CRC check, with the argument that an
>> unrecognized SPROM should be treated similarly to a non-existing one.
> 
> Have you maybe tried to look at the real solution?
> 

It could be a new SPROM revision, but brcmsmac still does SPROM access
on its own accord and would fail the probe sequence. So it is probably
something else.

SPROM configuration can differ between chipsets and have the following
variations:

1) external SPROM: when following conditions are true
	chipcommon.capabilities & 0x40000000
	chipcommon.sromcontrol & 0x00000001
2) on-chip OTP: when following conditions are true
	for 4313: chipcommon.chipstatus & 2
	for 43224/43225: true

The real solution would be to take the variations into account. I
started tinkering on it, but not completed yet.

Gr. AvS