diff mbox

PCI: iproc: fix 32-bit build error

Message ID 11199595.GgDE2yo8AA@wuerfel (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Arnd Bergmann Oct. 13, 2015, 8:02 p.m. UTC 
The iproc PCI driver tries to figure out whether the MMIO window has
a valid size, but does this using a 64-bit modulo operation, which
is not allowed on 32-bit kernels and leads to a link error:

drivers/built-in.o: In function `iproc_pcie_setup':
:(.text+0x4b798): undefined reference to `__aeabi_uldivmod'

This works around that error by using the div64_u64() function
provided by the kernel. While this is an expensive operation,
it is harmless because we only call it during the probing
of the driver.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 0ab99ca8eb6c ("PCI: iproc: Fix compile warnings")


--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

Hauke Mehrtens Oct. 13, 2015, 8:06 p.m. UTC | #1 
On 10/13/2015 10:02 PM, Arnd Bergmann wrote:
> The iproc PCI driver tries to figure out whether the MMIO window has
> a valid size, but does this using a 64-bit modulo operation, which
> is not allowed on 32-bit kernels and leads to a link error:
> 
> drivers/built-in.o: In function `iproc_pcie_setup':
> :(.text+0x4b798): undefined reference to `__aeabi_uldivmod'
> 
> This works around that error by using the div64_u64() function
> provided by the kernel. While this is an expensive operation,
> it is harmless because we only call it during the probing
> of the driver.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Fixes: 0ab99ca8eb6c ("PCI: iproc: Fix compile warnings")
> 
> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
> index f3481ddff344..abcb4be2ee19 100644
> --- a/drivers/pci/host/pcie-iproc.c
> +++ b/drivers/pci/host/pcie-iproc.c
> @@ -235,12 +235,13 @@ static void iproc_pcie_enable(struct iproc_pcie *pcie)
>   *
>   * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
>   */
> -static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> +int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,

Why are you removing the static here?

>  			       u64 pci_addr, resource_size_t size)
>  {
>  	struct iproc_pcie_ob *ob = &pcie->ob;
>  	unsigned i;
>  	u64 max_size = (u64)ob->window_size * MAX_NUM_OB_WINDOWS;
> +	u64 remainder;
>  
>  	if (size > max_size) {
>  		dev_err(pcie->dev,
> @@ -249,7 +250,8 @@ static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
>  		return -EINVAL;
>  	}
>  
> -	if (size % ob->window_size) {
> +	div64_u64_rem(size, ob->window_size, &remainder);
> +	if (remainder) {
>  		dev_err(pcie->dev,
>  			"res size %pap needs to be multiple of window size %pap\n",
>  			&size, &ob->window_size);
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Ray Jui Oct. 13, 2015, 8:11 p.m. UTC | #2 
On 10/13/2015 1:06 PM, Hauke Mehrtens wrote:
> On 10/13/2015 10:02 PM, Arnd Bergmann wrote:
>> The iproc PCI driver tries to figure out whether the MMIO window has
>> a valid size, but does this using a 64-bit modulo operation, which
>> is not allowed on 32-bit kernels and leads to a link error:
>>
>> drivers/built-in.o: In function `iproc_pcie_setup':
>> :(.text+0x4b798): undefined reference to `__aeabi_uldivmod'
>>
>> This works around that error by using the div64_u64() function
>> provided by the kernel. While this is an expensive operation,
>> it is harmless because we only call it during the probing
>> of the driver.
>>

Thanks, Arnd. Guess I did not see this issue when running on ARM32 based
platforms like Cygnus, because LAPE was not enabled by default for
multi_v7_defconfig. When LAPE is enabled, resource_size_t becomes 64-bit.

>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>> Fixes: 0ab99ca8eb6c ("PCI: iproc: Fix compile warnings")
>>
>> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
>> index f3481ddff344..abcb4be2ee19 100644
>> --- a/drivers/pci/host/pcie-iproc.c
>> +++ b/drivers/pci/host/pcie-iproc.c
>> @@ -235,12 +235,13 @@ static void iproc_pcie_enable(struct iproc_pcie *pcie)
>>   *
>>   * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
>>   */
>> -static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
>> +int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> 
> Why are you removing the static here?
> 

Yeah we should keep this function as static. The rest of this change
looks good!

>>  			       u64 pci_addr, resource_size_t size)
>>  {
>>  	struct iproc_pcie_ob *ob = &pcie->ob;
>>  	unsigned i;
>>  	u64 max_size = (u64)ob->window_size * MAX_NUM_OB_WINDOWS;
>> +	u64 remainder;
>>  
>>  	if (size > max_size) {
>>  		dev_err(pcie->dev,
>> @@ -249,7 +250,8 @@ static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
>>  		return -EINVAL;
>>  	}
>>  
>> -	if (size % ob->window_size) {
>> +	div64_u64_rem(size, ob->window_size, &remainder);
>> +	if (remainder) {
>>  		dev_err(pcie->dev,
>>  			"res size %pap needs to be multiple of window size %pap\n",
>>  			&size, &ob->window_size);
>>
> 

Thanks,

Ray
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Arnd Bergmann Oct. 13, 2015, 9 p.m. UTC | #3 
On Tuesday 13 October 2015 13:11:34 Ray Jui wrote:
> >> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
> >> index f3481ddff344..abcb4be2ee19 100644
> >> --- a/drivers/pci/host/pcie-iproc.c
> >> +++ b/drivers/pci/host/pcie-iproc.c
> >> @@ -235,12 +235,13 @@ static void iproc_pcie_enable(struct iproc_pcie *pcie)
> >>   *
> >>   * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
> >>   */
> >> -static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> >> +int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> > 
> > Why are you removing the static here?
> > 
> 
> Yeah we should keep this function as static. The rest of this change
> looks good!
> 

Sorry, this accidentally ended up in the patch when I marked the
function as global to track down how the division got called.

I'll send a new version.

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Kevin Hilman Oct. 13, 2015, 9:21 p.m. UTC | #4 
Arnd Bergmann <arnd@arndb.de> writes:

> The iproc PCI driver tries to figure out whether the MMIO window has
> a valid size, but does this using a 64-bit modulo operation, which
> is not allowed on 32-bit kernels and leads to a link error:
>
> drivers/built-in.o: In function `iproc_pcie_setup':
> :(.text+0x4b798): undefined reference to `__aeabi_uldivmod'
>
> This works around that error by using the div64_u64() function
> provided by the kernel. While this is an expensive operation,
> it is harmless because we only call it during the probing
> of the driver.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Fixes: 0ab99ca8eb6c ("PCI: iproc: Fix compile warnings")

Tested-by: Kevin Hilman <khilman@linaro.org>

Verified that this fixes the build failure on arm multi_v7_defconfig +
CONFIG_ARM_LPAE=y on top of next-20151013.

Kevin
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Bjorn Helgaas Oct. 15, 2015, 4 p.m. UTC | #5 
On Tue, Oct 13, 2015 at 11:00:31PM +0200, Arnd Bergmann wrote:
> On Tuesday 13 October 2015 13:11:34 Ray Jui wrote:
> > >> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
> > >> index f3481ddff344..abcb4be2ee19 100644
> > >> --- a/drivers/pci/host/pcie-iproc.c
> > >> +++ b/drivers/pci/host/pcie-iproc.c
> > >> @@ -235,12 +235,13 @@ static void iproc_pcie_enable(struct iproc_pcie *pcie)
> > >>   *
> > >>   * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
> > >>   */
> > >> -static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> > >> +int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
> > > 
> > > Why are you removing the static here?
> > > 
> > 
> > Yeah we should keep this function as static. The rest of this change
> > looks good!
> > 
> 
> Sorry, this accidentally ended up in the patch when I marked the
> function as global to track down how the division got called.
> 
> I'll send a new version.

Ping; I can easily fix up the static, but it'd be nice to have real acks
from Ray and Hauke.

Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Ray Jui Oct. 15, 2015, 4:19 p.m. UTC | #6 
On 10/15/2015 9:00 AM, Bjorn Helgaas wrote:
> On Tue, Oct 13, 2015 at 11:00:31PM +0200, Arnd Bergmann wrote:
>> On Tuesday 13 October 2015 13:11:34 Ray Jui wrote:
>>>>> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
>>>>> index f3481ddff344..abcb4be2ee19 100644
>>>>> --- a/drivers/pci/host/pcie-iproc.c
>>>>> +++ b/drivers/pci/host/pcie-iproc.c
>>>>> @@ -235,12 +235,13 @@ static void iproc_pcie_enable(struct iproc_pcie *pcie)
>>>>>   *
>>>>>   * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
>>>>>   */
>>>>> -static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
>>>>> +int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
>>>>
>>>> Why are you removing the static here?
>>>>
>>>
>>> Yeah we should keep this function as static. The rest of this change
>>> looks good!
>>>
>>
>> Sorry, this accidentally ended up in the patch when I marked the
>> function as global to track down how the division got called.
>>
>> I'll send a new version.
> 
> Ping; I can easily fix up the static, but it'd be nice to have real acks
> from Ray and Hauke.
> 
> Bjorn
> 

The current patch looks good to me except that iproc_pcie_setup_ob
should be kept static.

With static added back:
Acked-by: Ray Jui <rjui@broadcom.com>

Thanks,

Ray
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
index f3481ddff344..abcb4be2ee19 100644
--- a/drivers/pci/host/pcie-iproc.c
+++ b/drivers/pci/host/pcie-iproc.c
@@ -235,12 +235,13 @@  static void iproc_pcie_enable(struct iproc_pcie *pcie)
  *
  * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
  */
-static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
+int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
 			       u64 pci_addr, resource_size_t size)
 {
 	struct iproc_pcie_ob *ob = &pcie->ob;
 	unsigned i;
 	u64 max_size = (u64)ob->window_size * MAX_NUM_OB_WINDOWS;
+	u64 remainder;
 
 	if (size > max_size) {
 		dev_err(pcie->dev,
@@ -249,7 +250,8 @@  static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
 		return -EINVAL;
 	}
 
-	if (size % ob->window_size) {
+	div64_u64_rem(size, ob->window_size, &remainder);
+	if (remainder) {
 		dev_err(pcie->dev,
 			"res size %pap needs to be multiple of window size %pap\n",
 			&size, &ob->window_size);