[PATCH V6 2/5] PCI/ACPI: Check platform specific ECAM quirks
Tomasz Nowicki
tn at semihalf.com
Mon Sep 12 22:58:02 PDT 2016
On 13.09.2016 00:47, Duc Dang wrote:
> On Mon, Sep 12, 2016 at 3:24 PM, Duc Dang <dhdang at apm.com> wrote:
>> On Fri, Sep 9, 2016 at 12:24 PM, Tomasz Nowicki <tn at semihalf.com> wrote:
>>>
>>> Some platforms may not be fully compliant with generic set of PCI config
>>> accessors. For these cases we implement the way to overwrite CFG accessors
>>> set and configuration space range.
>>>
>>> In first place pci_mcfg_parse() saves machine's IDs and revision number
>>> (these come from MCFG header) in order to match against known quirk entries.
>>> Then the algorithm traverses available quirk list (static array),
>>> matches against <oem_id, oem_table_id, rev, domain, bus number range> and
>>> returns custom PCI config ops and/or CFG resource structure.
>>>
>>> When adding new quirk there are two possibilities:
>>> 1. Override default pci_generic_ecam_ops ops but CFG resource comes from MCFG
>>> { "OEM_ID", "OEM_TABLE_ID", <REV>, <DOMAIN>, <BUS_NR>, &foo_ops, MCFG_RES_EMPTY },
>>> 2. Override default pci_generic_ecam_ops ops and CFG resource. For this case
>>> it is also allowed get CFG resource from quirk entry w/o having it in MCFG.
>>> { "OEM_ID", "OEM_TABLE_ID", <REV>, <DOMAIN>, <BUS_NR>, &boo_ops,
>>> DEFINE_RES_MEM(START, SIZE) },
>>>
>>> pci_generic_ecam_ops and MCFG entries will be used for platforms
>>> free from quirks.
>>>
>>> Signed-off-by: Tomasz Nowicki <tn at semihalf.com>
>>> Signed-off-by: Dongdong Liu <liudongdong3 at huawei.com>
>>> Signed-off-by: Christopher Covington <cov at codeaurora.org>
>>> ---
>>> drivers/acpi/pci_mcfg.c | 80 +++++++++++++++++++++++++++++++++++++++++++++----
>>> 1 file changed, 74 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>> index ffcc651..2b8acc7 100644
>>> --- a/drivers/acpi/pci_mcfg.c
>>> +++ b/drivers/acpi/pci_mcfg.c
>>> @@ -32,6 +32,59 @@ struct mcfg_entry {
>>> u8 bus_start;
>>> u8 bus_end;
>>> };
>>> +struct mcfg_fixup {
>>> + char oem_id[ACPI_OEM_ID_SIZE + 1];
>>> + char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
>>> + u32 oem_revision;
>>> + u16 seg;
>>> + struct resource bus_range;
>>> + struct pci_ecam_ops *ops;
>>> + struct resource cfgres;
>>> +};
>>> +
>>> +#define MCFG_DOM_ANY (-1)
>>> +#define MCFG_BUS_RANGE(start, end) DEFINE_RES_NAMED((start), \
>>> + ((end) - (start) + 1), \
>>> + NULL, IORESOURCE_BUS)
>>> +#define MCFG_BUS_ANY MCFG_BUS_RANGE(0x0, 0xff)
>>> +#define MCFG_RES_EMPTY DEFINE_RES_NAMED(0, 0, NULL, 0)
>>> +
>>> +static struct mcfg_fixup mcfg_quirks[] = {
>>> +/* { OEM_ID, OEM_TABLE_ID, REV, DOMAIN, BUS_RANGE, cfgres, ops }, */
>>> +};
>>> +
>>> +static char mcfg_oem_id[ACPI_OEM_ID_SIZE];
>>> +static char mcfg_oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
>>> +static u32 mcfg_oem_revision;
>>> +
>>> +static void pci_mcfg_match_quirks(struct acpi_pci_root *root,
>>> + struct resource *cfgres,
>>> + struct pci_ecam_ops **ecam_ops)
>>> +{
>>> + struct mcfg_fixup *f;
>>> + int i;
>>> +
>>> + /*
>>> + * First match against PCI topology <domain:bus> then use OEM ID, OEM
>>> + * table ID, and OEM revision from MCFG table standard header.
>>> + */
>>> + for (i = 0, f = mcfg_quirks; i < ARRAY_SIZE(mcfg_quirks); i++, f++) {
>>> + if (f->seg == root->segment &&
>>
>> Is dropping the comparison with MCFG_DOM_ANY intended? It is useful if
>> all the controllers (segs) can use the same quirk (X-Gene case).
>> If you decide to drop it, then we can remove MCFG_DOM_ANY definition as well.
>>
>>> + resource_contains(&f->bus_range, &root->secondary) &&
>>> + !memcmp(f->oem_id, mcfg_oem_id, ACPI_OEM_ID_SIZE) &&
>>> + !memcmp(f->oem_table_id, mcfg_oem_table_id,
>>> + ACPI_OEM_TABLE_ID_SIZE) &&
>>> + f->oem_revision == mcfg_oem_revision) {
>>> + if (f->cfgres.start)
>>> + *cfgres = f->cfgres;
>>> + if (f->ops)
>>> + *ecam_ops = f->ops;
>>> + dev_info(&root->device->dev, "Applying PCI MCFG quirks for %s %s rev: %d\n",
>>> + f->oem_id, f->oem_table_id, f->oem_revision);
>>> + return;
>>> + }
>>> + }
>>> +}
>>>
>>> /* List to save MCFG entries */
>>> static LIST_HEAD(pci_mcfg_list);
>>> @@ -61,14 +114,24 @@ int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres,
>>>
>>> }
>>>
>>> - if (!root->mcfg_addr)
>>> - return -ENXIO;
>>> -
>>> skip_lookup:
>>> memset(&res, 0, sizeof(res));
>>> - res.start = root->mcfg_addr + (bus_res->start << 20);
>>> - res.end = res.start + (resource_size(bus_res) << 20) - 1;
>>> - res.flags = IORESOURCE_MEM;
>>> + if (root->mcfg_addr) {
>>> + res.start = root->mcfg_addr + (bus_res->start << 20);
>>> + res.end = res.start + (resource_size(bus_res) << 20) - 1;
>>> + res.flags = IORESOURCE_MEM;
>>> + }
>>> +
>>> + /*
>>> + * Let to override default ECAM ops and CFG resource range.
>>> + * Also, this might even retrieve CFG resource range in case MCFG
>>> + * does not have it. Invalid CFG start address means MCFG firmware bug
>>> + * or we need another quirk in array.
>>> + */
>>> + pci_mcfg_match_quirks(root, &res, &ops);
>>> + if (!res.start)
>>> + return -ENXIO;
>>> +
>>> *cfgres = res;
>>> *ecam_ops = ops;
>>> return 0;
>>> @@ -101,6 +164,11 @@ static __init int pci_mcfg_parse(struct acpi_table_header *header)
>>> list_add(&e->list, &pci_mcfg_list);
>>> }
>>>
>>> + /* Save MCFG IDs and revision for quirks matching */
>>> + memcpy(mcfg_oem_id, header->oem_id, ACPI_OEM_ID_SIZE);
>>> + memcpy(mcfg_oem_table_id, header->oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
>>> + mcfg_oem_revision = header->revision;
>
> I think this is a typo, it should be:
> mcfg_oem_revision = header->oem_revision;
You are right, header->oem_revision should be assigned.
Thanks!
Tomasz
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