Hi,
Thanks for looking at this.
On 8/6/21 5:12 PM, Bjorn Helgaas wrote:
In subject, this or similar would match history:
PCI/ACPI: Add Broadcom bcm2711 MCFG quirk
On Thu, Aug 05, 2021 at 04:12:00PM -0500, Jeremy Linton wrote:
Now that we have a bcm2711 quirk, we need to be able to
detect it when the MCFG is missing. Use a namespace
property as an alternative to the MCFG OEM.
Rewrap to use ~75 columns.
Mention the DT namespace property here.
Signed-off-by: Jeremy Linton <jeremy.linton@xxxxxxx>
---
drivers/acpi/pci_mcfg.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index 53cab975f612..7d77fc72c2a4 100644
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c
@@ -169,6 +169,9 @@ static struct mcfg_fixup mcfg_quirks[] = {
ALTRA_ECAM_QUIRK(1, 13),
ALTRA_ECAM_QUIRK(1, 14),
ALTRA_ECAM_QUIRK(1, 15),
+
+ { "bcm2711", "", 0, 0, MCFG_BUS_ANY, &bcm2711_pcie_ops,
+ DEFINE_RES_MEM(0xFD500000, 0xA000) },
};
static char mcfg_oem_id[ACPI_OEM_ID_SIZE];
@@ -198,8 +201,19 @@ static void pci_mcfg_apply_quirks(struct acpi_pci_root *root,
u16 segment = root->segment;
struct resource *bus_range = &root->secondary;
struct mcfg_fixup *f;
+ const char *soc;
int i;
+ /*
+ * This could be a machine with a PCI/SMC conduit,
+ * which means it doens't have MCFG. Get the machineid from
+ * the namespace definition instead.
s/SMC/SMCCC/ ? Cover letter uses SMCCC (not sure it's relevant anyway)
s/doens't/doesn't/
Rewrap comment to use ~80 columns.
Seems pretty reasonable that a platform without standard ECAM might
not have MCFG, since MCFG basically implies ECAM.
Sure, on all the above comments.
Is "linux,pcie-quirk" the right property to look for? It doesn't
sound very generic, and it doesn't sound like anything related to
ECAM. Is it new? I don't see it in the tree yet. Should it be in
Documentation/devicetree/bindings/pci/pci.txt so we don't get a
different property name for every new platform?
Yes, I made it up. Someone else commented about the "linux," partially
because it should be "linux-" to conform with
https://github.com/UEFI/DSD-Guide. But also in the same context of it
being linux specific. I think that guide is where it should end up,
rather than the devicetree bindings.
I guess we can request addition to the uefi- but that seems like a
mistake this is really (hopefully?) a Linux specific properly as other
OS's will simply use the SMC. I think we could request another prefix if
we come up with a good one and think it belongs in that guide.
+ */
+ if (!fwnode_property_read_string(acpi_fwnode_handle(root->device),
+ "linux,pcie-quirk", &soc)) {
+ memcpy(mcfg_oem_id, soc, ACPI_OEM_ID_SIZE);
+ }
+
for (i = 0, f = mcfg_quirks; i < ARRAY_SIZE(mcfg_quirks); i++, f++) {
if (pci_mcfg_quirk_matches(f, segment, bus_range)) {
if (f->cfgres.start)
--
2.31.1
