Re: [PATCH] platform/x86: amd-pmc: Fix undefined reference to __udivdi3

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 7/16/21 5:38 PM, Shyam Sundar S K wrote:
> It was reported that on i386 config
> 
> ------
> on i386:
> 
> ld: drivers/platform/x86/amd-pmc.o: in function `s0ix_stats_show':
> amd-pmc.c:(.text+0x100): undefined reference to `__udivdi3'
> -------
> 
> The reason for this is that 64-bit integer division is not supported
> on 32-bit architecture. Use do_div macro to fix this.
> 
> Fixes: b9a4fa6978be ("platform/x86: amd-pmc: Add support for logging s0ix counters")
> Reported-by: Randy Dunlap <rdunlap@infradead.org>
> Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

I will also apply this to the fixes branch and include it in my
upcoming v5.14 pdx86 fixes pull-req to Linus.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans


> ---
>  drivers/platform/x86/amd-pmc.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c
> index 680f94c7e075..45ce1d5e1e6d 100644
> --- a/drivers/platform/x86/amd-pmc.c
> +++ b/drivers/platform/x86/amd-pmc.c
> @@ -189,7 +189,8 @@ static int s0ix_stats_show(struct seq_file *s, void *unused)
>  	exit_time = exit_time << 32 | ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_L_OFFSET);
>  
>  	/* It's in 48MHz. We need to convert it */
> -	residency = (exit_time - entry_time) / 48;
> +	residency = exit_time - entry_time;
> +	do_div(residency, 48);
>  
>  	seq_puts(s, "=== S0ix statistics ===\n");
>  	seq_printf(s, "S0ix Entry Time: %lld\n", entry_time);
>