Messages in this thread | | | Subject | Re: [Linaro-acpi] [PATCH V6 12/13] pci, pci-thunder-ecam: Add ACPI support for ThunderX ECAM. | From | Tomasz Nowicki <> | Date | Tue, 19 Apr 2016 13:22:29 +0200 |
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On 19.04.2016 13:12, Graeme Gregory wrote: > On Tue, Apr 19, 2016 at 11:41:29AM +0100, G Gregory wrote: >> On 19 April 2016 at 11:26, Tomasz Nowicki <tn@semihalf.com> wrote: >>> On 15.04.2016 19:06, Tomasz Nowicki wrote: >>>> >>>> Passes 1.x miss PCI enhanced allocation (EA) header for fixed-BARs, >>>> thus these passes should use Cavium-specific config access functions >>>> that synthesize the missing EA capabilities. >>>> >>>> We already have DT driver which addresses errata requirements and >>>> allows to use special PCI config accessors. Currently this driver uses >>>> compatible = "cavium,pci-host-thunder-ecam" to mach against the errata. >>>> For ACPI case we need explicit errata number and corresponding >>>> DECLARE_ACPI_MCFG_FIXUP fixup code. >>>> >>>> Signed-off-by: Tomasz Nowicki <tn@semihalf.com> >>>> --- >>>> arch/arm64/Kconfig | 14 ++++++++++++++ >>>> arch/arm64/include/asm/cpufeature.h | 3 ++- >>>> arch/arm64/kernel/cpu_errata.c | 8 ++++++++ >>>> drivers/pci/host/pci-thunder-ecam.c | 35 >>>> +++++++++++++++++++++++++++++++++++ >>>> 4 files changed, 59 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >>>> index 1bded87..b7614b8 100644 >>>> --- a/arch/arm64/Kconfig >>>> +++ b/arch/arm64/Kconfig >>>> @@ -445,6 +445,20 @@ config CAVIUM_ERRATUM_27456 >>>> >>>> If unsure, say Y. >>>> >>>> +config CAVIUM_ERRATUM_24575 >>>> + bool "Cavium erratum 24575: Enhanced Allocation (EA) emualaion" >>>> + default y >>>> + help >>>> + Enable workaround for erratum 24575. >>>> + >>>> + Early versions of the Cavium Thunder CN88XX processor are >>>> missing >>>> + Enhanced Allocation (EA) capabilities for the fixed BAR >>>> addresses used >>>> + by the on-SoC hardware blocks. The erratum adds config access >>>> + functions that synthesize the missing EA capabilities for >>>> versions >>>> + that are missing that information. >>>> + >>>> + If unsure, say Y. >>>> + >>>> endmenu >>>> >>>> >>>> diff --git a/arch/arm64/include/asm/cpufeature.h >>>> b/arch/arm64/include/asm/cpufeature.h >>>> index b9b6494..a78364e 100644 >>>> --- a/arch/arm64/include/asm/cpufeature.h >>>> +++ b/arch/arm64/include/asm/cpufeature.h >>>> @@ -35,8 +35,9 @@ >>>> #define ARM64_ALT_PAN_NOT_UAO 10 >>>> #define ARM64_HAS_VIRT_HOST_EXTN 11 >>>> #define ARM64_WORKAROUND_CAVIUM_27456 12 >>>> +#define ARM64_WORKAROUND_CAVIUM_24575 13 >>>> >>>> -#define ARM64_NCAPS 13 >>>> +#define ARM64_NCAPS 14 >>>> >>>> #ifndef __ASSEMBLY__ >>>> >>>> diff --git a/arch/arm64/kernel/cpu_errata.c >>>> b/arch/arm64/kernel/cpu_errata.c >>>> index 06afd04..89c13d7 100644 >>>> --- a/arch/arm64/kernel/cpu_errata.c >>>> +++ b/arch/arm64/kernel/cpu_errata.c >>>> @@ -97,6 +97,14 @@ const struct arm64_cpu_capabilities arm64_errata[] = { >>>> (1 << MIDR_VARIANT_SHIFT) | 1), >>>> }, >>>> #endif >>>> +#ifdef CONFIG_CAVIUM_ERRATUM_24575 >>>> + { >>>> + /* Cavium ThunderX, pass 1.x */ >>>> + .desc = "Cavium erratum 24575", >>>> + .capability = ARM64_WORKAROUND_CAVIUM_24575, >>>> + MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01), >>>> + }, >>>> +#endif >>>> { >>>> } >>>> }; >>>> diff --git a/drivers/pci/host/pci-thunder-ecam.c >>>> b/drivers/pci/host/pci-thunder-ecam.c >>>> index f67c6d7..01de697 100644 >>>> --- a/drivers/pci/host/pci-thunder-ecam.c >>>> +++ b/drivers/pci/host/pci-thunder-ecam.c >>>> @@ -11,10 +11,14 @@ >>>> #include <linux/ioport.h> >>>> #include <linux/of_pci.h> >>>> #include <linux/of.h> >>>> +#include <linux/pci-acpi.h> >>>> #include <linux/platform_device.h> >>>> >>>> +#include <asm/virt.h> >>>> + >>>> #include "../ecam.h" >>>> >>>> + >>>> static void set_val(u32 v, int where, int size, u32 *val) >>>> { >>>> int shift = (where & 3) * 8; >>>> @@ -376,5 +380,36 @@ static struct platform_driver thunder_ecam_driver = { >>>> }; >>>> module_platform_driver(thunder_ecam_driver); >>>> >>>> +#ifdef CONFIG_ACPI >>>> + >>>> +static bool needs_cavium_erratum_24575(struct pci_cfg_fixup *fixup, >>>> + struct acpi_pci_root *root) >>>> +{ >>>> + /* >>>> + * We must match errata code and be hypervisor, quirk does not >>>> apply >>>> + * for virtual machines. >>>> + */ >>>> + return cpus_have_cap(ARM64_WORKAROUND_CAVIUM_24575) && >>>> + is_hyp_mode_available(); >>>> +} >>>> + >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 0, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 1, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 2, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 3, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 10, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 11, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 12, PCI_MCFG_BUS_ANY); >>>> +DECLARE_ACPI_MCFG_FIXUP(NULL, needs_cavium_erratum_24575, >>>> &pci_thunder_ecam_ops, >>>> + 13, PCI_MCFG_BUS_ANY); >>>> +#endif >>>> + >>> >>> >>> I wonder if we can identify quirk based on _DSD properties, like that: >>> >>> Name (_DSD, Package () { >>> ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), >>> Package () { >>> Package (2) {"cavium,pci-host-thunder-ecam", 1}, >>> } >>> }) >>> >>> similar for PEM driver: >>> >>> Name (_DSD, Package () { >>> ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), >>> Package () { >>> Package (2) {"cavium,pci-host-thunder-pem", 1}, >>> } >>> }) >>> >>> Do you think it is right thing to do? >>> >> >> Well if your adding new properties why not add a Cavium specific _CID? >> > > For clarity what I mean is something like this allowed. > > Device (PCI0) > { > Name (_HID, EisaId ("PNP0A08")) > Name (_CID, EisaId ("PNP0A03")) > Name (_HID, "CAV0666")) // Cavium Quirky Hardware > > .... > > } >
Rafael, Bjorn, what do you think?
Tomasz
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