Re: Info: mapping multiple BARs. Your kernel is fine.

Zhang Rui
2014-03-20T13:43:14Z

On Thu, 2014-03-20 at 16:16 +0800, Yan, Zheng wrote:
> On 03/20/2014 03:53 PM, Zhang, Rui wrote:
> > The resource length is also hardcoded to 0x6000, right?
> > This is probably a problem, because
> > only if the resource length read from PCI config space is larger than 0x4000,
> > drivers/pnp/quirks.c will detect the conflict and disable the PNP0C02
> > resource 0xfed10000 - 0xfed13fff, and the PCI device can request this
> > resource successfully.
> > In order to check this, can you please attach the dmesg output after boot?
>
> maybe the issue can be fixed by below untested patch
>
> ---
> diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> index fd5e883..2b3d834 100644
> --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
> @@ -1701,7 +1701,7 @@ static struct uncore_event_desc snb_uncore_imc_events[] = {
> #define SNB_UNCORE_PCI_IMC_BAR_OFFSET 0x48
>
> /* page size multiple covering all config regs */
> -#define SNB_UNCORE_PCI_IMC_MAP_SIZE 0x6000
> +#define SNB_UNCORE_PCI_IMC_MAP_SIZE 0x8
>
> #define SNB_UNCORE_PCI_IMC_DATA_READS 0x1
> #define SNB_UNCORE_PCI_IMC_DATA_READS_BASE 0x5050
> @@ -1736,7 +1736,8 @@ static void snb_uncore_imc_init_box(struct intel_uncore_box *box)
>
> addr &= ~(PAGE_SIZE - 1);
>
> - box->io_addr = ioremap(addr, SNB_UNCORE_PCI_IMC_MAP_SIZE);
> + box->io_addr = ioremap(addr + SNB_UNCORE_PCI_IMC_CTR_BASE,
> + SNB_UNCORE_PCI_IMC_MAP_SIZE);

you're remapping 0xfed15050 - 0xfed1b04f instead of 0xfed10000 -
0xfed15fff ?
I do not quite understand this, but apparently this is not a FIX.
If it works for this problem, it is because 0xfed15050 - 0xfed1b04f
happens to be not conflict with any resource reserved by PNP system
driver, on this machine.

thanks,
rui

> box->hrtimer_duration = UNCORE_SNB_IMC_HRTIMER_INTERVAL;
> }
>
> @@ -1832,7 +1833,7 @@ static int snb_uncore_imc_event_init(struct perf_event *event)
> }
>
> /* must be done before validate_group */
> - event->hw.event_base = base;
> + event->hw.event_base = base - SNB_UNCORE_PCI_IMC_CTR_BASE;
> event->hw.config = cfg;
> event->hw.idx = idx;
>