[PATCH] ssb: check for flash presentence

[PATCH] ssb: check for flash presentence

[Rafał Miłecki]

We can not assume parallel flash is always present, there are boards
with *serial* flash and probably some without flash at all.
Define some bits by the way.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
---
 drivers/ssb/driver_mipscore.c             |   28 +++++++++++++++++++++-------
 include/linux/ssb/ssb_driver_chipcommon.h |    4 +++-
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/drivers/ssb/driver_mipscore.c b/drivers/ssb/driver_mipscore.c
index 7e2ddc0..c625086 100644
--- a/drivers/ssb/driver_mipscore.c
+++ b/drivers/ssb/driver_mipscore.c
@@ -190,16 +190,30 @@ static void ssb_mips_flash_detect(struct ssb_mipscore *mcore)
 {
 	struct ssb_bus *bus = mcore->dev->bus;
 
-	mcore->flash_buswidth = 2;
-	if (bus->chipco.dev) {
-		mcore->flash_window = 0x1c000000;
-		mcore->flash_window_size = 0x02000000;
+	/* When there is no chipcommon on the bus there is 4MB flash */
+	if (!bus->chipco.dev) {
+		mcore->flash_buswidth = 2;
+		mcore->flash_window = SSB_FLASH1;
+		mcore->flash_window_size = SSB_FLASH1_SZ;
+		return;
+	}
+
+	/* There is ChipCommon, so use it to read info about flash */
+	switch (bus->chipco.capabilities & SSB_CHIPCO_CAP_FLASHT) {
+	case SSB_CHIPCO_FLASHT_STSER:
+	case SSB_CHIPCO_FLASHT_ATSER:
+		pr_err("Serial flash not supported\n");
+		break;
+	case SSB_CHIPCO_FLASHT_PARA:
+		pr_debug("Found parallel flash\n");
+		mcore->flash_window = SSB_FLASH2;
+		mcore->flash_window_size = SSB_FLASH2_SZ;
 		if ((ssb_read32(bus->chipco.dev, SSB_CHIPCO_FLASH_CFG)
 		               & SSB_CHIPCO_CFG_DS16) == 0)
 			mcore->flash_buswidth = 1;
-	} else {
-		mcore->flash_window = 0x1fc00000;
-		mcore->flash_window_size = 0x00400000;
+		else
+			mcore->flash_buswidth = 2;
+		break;
 	}
 }
 
diff --git a/include/linux/ssb/ssb_driver_chipcommon.h b/include/linux/ssb/ssb_driver_chipcommon.h
index 1a6b004..c2b02a5 100644
--- a/include/linux/ssb/ssb_driver_chipcommon.h
+++ b/include/linux/ssb/ssb_driver_chipcommon.h
@@ -504,7 +504,9 @@
 #define SSB_CHIPCO_FLASHCTL_ST_SE	0x02D8		/* Sector Erase */
 #define SSB_CHIPCO_FLASHCTL_ST_BE	0x00C7		/* Bulk Erase */
 #define SSB_CHIPCO_FLASHCTL_ST_DP	0x00B9		/* Deep Power-down */
-#define SSB_CHIPCO_FLASHCTL_ST_RSIG	0x03AB		/* Read Electronic Signature */
+#define SSB_CHIPCO_FLASHCTL_ST_RES	0x03AB		/* Read Electronic Signature */
+#define SSB_CHIPCO_FLASHCTL_ST_CSA	0x1000		/* Keep chip select asserted */
+#define SSB_CHIPCO_FLASHCTL_ST_SSE	0x0220		/* Sub-sector Erase */
 
 /* Status register bits for ST flashes */
 #define SSB_CHIPCO_FLASHSTA_ST_WIP	0x01		/* Write In Progress */
-- 
1.7.7

Re: [PATCH] ssb: check for flash presentence

[Hauke Mehrtens]

On 08/08/2012 07:37 PM, Rafał Miłecki wrote:
> We can not assume parallel flash is always present, there are boards
> with *serial* flash and probably some without flash at all.
> Define some bits by the way.
> 
> Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
> Cc: Hauke Mehrtens <hauke@hauke-m.de>
> ---
>  drivers/ssb/driver_mipscore.c             |   28 +++++++++++++++++++++-------
>  include/linux/ssb/ssb_driver_chipcommon.h |    4 +++-
>  2 files changed, 24 insertions(+), 8 deletions(-)

I haven't tested this patch on my devices, but it looks good to me.
In an additional patch we also need a bool or something like this to
indicate if there is a parallel, serial or no flash present on the SoC.
For serial and parallel flash it is not possible to have both of them.

Reviewed-by: Hauke Mehrtens <hauke@hauke-m.de>

Re: [PATCH] ssb: check for flash presentence

[Rafał Miłecki]

2012/8/10 Hauke Mehrtens <hauke@hauke-m.de>:
> On 08/08/2012 07:37 PM, Rafał Miłecki wrote:
>> We can not assume parallel flash is always present, there are boards
>> with *serial* flash and probably some without flash at all.
>> Define some bits by the way.
>>
>> Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
>> Cc: Hauke Mehrtens <hauke@hauke-m.de>
>> ---
>>  drivers/ssb/driver_mipscore.c             |   28 +++++++++++++++++++++-------
>>  include/linux/ssb/ssb_driver_chipcommon.h |    4 +++-
>>  2 files changed, 24 insertions(+), 8 deletions(-)
>
> I haven't tested this patch on my devices, but it looks good to me.
> In an additional patch we also need a bool or something like this to
> indicate if there is a parallel, serial or no flash present on the SoC.
> For serial and parallel flash it is not possible to have both of them.

Can I ask why? In theory there are 2 different possible mappings
(SSB_FLASH1 and SSB_FLASH2).

-- 
Rafał

Re: [PATCH] ssb: check for flash presentence

[Hauke Mehrtens]

On 08/10/2012 03:37 PM, Rafał Miłecki wrote:
> 2012/8/10 Hauke Mehrtens <hauke@hauke-m.de>:
>> On 08/08/2012 07:37 PM, Rafał Miłecki wrote:
>>> We can not assume parallel flash is always present, there are boards
>>> with *serial* flash and probably some without flash at all.
>>> Define some bits by the way.
>>>
>>> Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
>>> Cc: Hauke Mehrtens <hauke@hauke-m.de>
>>> ---
>>>  drivers/ssb/driver_mipscore.c             |   28 +++++++++++++++++++++-------
>>>  include/linux/ssb/ssb_driver_chipcommon.h |    4 +++-
>>>  2 files changed, 24 insertions(+), 8 deletions(-)
>>
>> I haven't tested this patch on my devices, but it looks good to me.
>> In an additional patch we also need a bool or something like this to
>> indicate if there is a parallel, serial or no flash present on the SoC.
>> For serial and parallel flash it is not possible to have both of them.
> 
> Can I ask why? In theory there are 2 different possible mappings
> (SSB_FLASH1 and SSB_FLASH2).
> 
Ok, it could be possible, but the configuration bits in the cc core
capabilities currently do not allow such a configuration and I have
never heard of such a device.