Re: [PATCH v4] mtd: parsers: bcm63xx: simplify CFE detection

From: Guenter Roeck <linux@roeck-us.net>
To: "Naresh Kamboju" <naresh.kamboju@linaro.org>,
	"Álvaro Fernández Rojas" <noltari@gmail.com>,
	linux-mips@vger.kernel.org
Cc: tsbogend@alpha.franken.de,
	Florian Fainelli <f.fainelli@gmail.com>,
	bcm-kernel-feedback-list@broadcom.com,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	jonas.gorski@gmail.com, Linus Walleij <linus.walleij@linaro.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	open list <linux-kernel@vger.kernel.org>,
	linux-mtd@lists.infradead.org, lkft-triage@lists.linaro.org
Subject: Re: [PATCH v4] mtd: parsers: bcm63xx: simplify CFE detection
Date: Mon, 21 Sep 2020 20:26:19 -0700	[thread overview]
Message-ID: <bff67b4c-4fa0-2441-ddbe-15366c8601d1@roeck-us.net> (raw)
In-Reply-To: <CA+G9fYvGkowdQmi1eBfoq2dhzBfgkFh9+7tgdNw75LydxkAEPw@mail.gmail.com>

On 9/21/20 8:18 PM, Naresh Kamboju wrote:
> On Fri, 14 Aug 2020 at 14:26, Guenter Roeck <linux@roeck-us.net> wrote:
>>
>> On Mon, Jun 15, 2020 at 11:17:40AM +0200, Álvaro Fernández Rojas wrote:
>>> Instead of trying to parse CFE version string, which is customized by some
>>> vendors, let's just check that "CFE1" was passed on argument 3.
>>>
>>> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
>>> Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
>>> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
>>
> 
> We still see mips: allmodconfig build failure on Linus tree
> 

Yes, same here.

Guenter

> make -sk KBUILD_BUILD_USER=TuxBuild -C/linux ARCH=mips
> CROSS_COMPILE=mips-linux-gnu- HOSTCC=gcc CC="sccache
> mips-linux-gnu-gcc" O=build allmodconfig
> 
> make -sk KBUILD_BUILD_USER=TuxBuild -C/linux -j16 ARCH=mips
> CROSS_COMPILE=mips-linux-gnu- HOSTCC=gcc CC="sccache
> mips-linux-gnu-gcc" O=build
> 
> 
>> mips:allmodconfig:
>>
>> ERROR: modpost: "fw_arg3" [drivers/mtd/parsers/bcm63xxpart.ko] undefined!
> 
> ERROR: modpost: "fw_arg3" [drivers/mtd/parsers/bcm63xxpart.ko] undefined!
> 
> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
> 
> Full build link,
> https://builds.tuxbuild.com/Sm59_9tjFMpIvT27qf5kNA/build.log
> 
>>
>> This is not surprising, since fw_arg3 is not exported.
>>
>> Guenter
>>
>>> ---
>>>  v4: shorten conditional compilation part as suggested by Miquèl.
>>>  v3: keep COMPILE_TEST compatibility by adding a new function that only checks
>>>      fw_arg3 when CONFIG_MIPS is defined.
>>>  v2: use CFE_EPTSEAL definition and avoid using an additional function.
>>>
>>>  drivers/mtd/parsers/bcm63xxpart.c | 32 ++++++++++++-------------------
>>>  1 file changed, 12 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/drivers/mtd/parsers/bcm63xxpart.c b/drivers/mtd/parsers/bcm63xxpart.c
>>> index 78f90c6c18fd..b15bdadaedb5 100644
>>> --- a/drivers/mtd/parsers/bcm63xxpart.c
>>> +++ b/drivers/mtd/parsers/bcm63xxpart.c
>>> @@ -22,6 +22,11 @@
>>>  #include <linux/mtd/partitions.h>
>>>  #include <linux/of.h>
>>>
>>> +#ifdef CONFIG_MIPS
>>> +#include <asm/bootinfo.h>
>>> +#include <asm/fw/cfe/cfe_api.h>
>>> +#endif /* CONFIG_MIPS */
>>> +
>>>  #define BCM963XX_CFE_BLOCK_SIZE              SZ_64K  /* always at least 64KiB */
>>>
>>>  #define BCM963XX_CFE_MAGIC_OFFSET    0x4e0
>>> @@ -32,28 +37,15 @@
>>>  #define STR_NULL_TERMINATE(x) \
>>>       do { char *_str = (x); _str[sizeof(x) - 1] = 0; } while (0)
>>>
>>> -static int bcm63xx_detect_cfe(struct mtd_info *master)
>>> +static inline int bcm63xx_detect_cfe(void)
>>>  {
>>> -     char buf[9];
>>> -     int ret;
>>> -     size_t retlen;
>>> +     int ret = 0;
>>>
>>> -     ret = mtd_read(master, BCM963XX_CFE_VERSION_OFFSET, 5, &retlen,
>>> -                    (void *)buf);
>>> -     buf[retlen] = 0;
>>> +#ifdef CONFIG_MIPS
>>> +     ret = (fw_arg3 == CFE_EPTSEAL);
>>> +#endif /* CONFIG_MIPS */
>>>
>>> -     if (ret)
>>> -             return ret;
>>> -
>>> -     if (strncmp("cfe-v", buf, 5) == 0)
>>> -             return 0;
>>> -
>>> -     /* very old CFE's do not have the cfe-v string, so check for magic */
>>> -     ret = mtd_read(master, BCM963XX_CFE_MAGIC_OFFSET, 8, &retlen,
>>> -                    (void *)buf);
>>> -     buf[retlen] = 0;
>>> -
>>> -     return strncmp("CFE1CFE1", buf, 8);
>>> +     return ret;
>>>  }
>>>
>>>  static int bcm63xx_read_nvram(struct mtd_info *master,
>>> @@ -138,7 +130,7 @@ static int bcm63xx_parse_cfe_partitions(struct mtd_info *master,
>>>       struct bcm963xx_nvram *nvram = NULL;
>>>       int ret;
>>>
>>> -     if (bcm63xx_detect_cfe(master))
>>> +     if (!bcm63xx_detect_cfe())
>>>               return -EINVAL;
>>>
>>>       nvram = vzalloc(sizeof(*nvram));