drivers/pci: Add ecam quirk for Ampere Altra SOC.

Ampere Altra SOC only supports 32bit PCI ecam read. Therefore, add an ecam quirk for the platform. Signed-off-by: Tuan Phan <[email protected]>
AmpereComputing · Jun 30, 2020 · 0d8dd94 · 0d8dd94
1 parent 283833f
commit 0d8dd94
Show file tree

Hide file tree

Showing 3 changed files with 30 additions and 0 deletions.
diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
@@ -146,6 +146,26 @@ static struct mcfg_fixup mcfg_quirks[] = {
 	{"BRCM  ", "BRCM-SRX", rev, seg, MCFG_BUS_ANY, \
 		&iproc_pcie_paxcv2_ecam_ops }
 	BCM_ECAM_MCFG(1, 8),
+
+#define AMPERE_ECAM32(rev, seg) \
+	{ "Ampere", "Altra   ", rev, seg, MCFG_BUS_ANY, &pci_32b_read_ops }
+
+	AMPERE_ECAM32(1, 0),
+	AMPERE_ECAM32(1, 1),
+	AMPERE_ECAM32(1, 2),
+	AMPERE_ECAM32(1, 3),
+	AMPERE_ECAM32(1, 4),
+	AMPERE_ECAM32(1, 5),
+	AMPERE_ECAM32(1, 6),
+	AMPERE_ECAM32(1, 7),
+	AMPERE_ECAM32(1, 8),
+	AMPERE_ECAM32(1, 9),
+	AMPERE_ECAM32(1, 10),
+	AMPERE_ECAM32(1, 11),
+	AMPERE_ECAM32(1, 12),
+	AMPERE_ECAM32(1, 13),
+	AMPERE_ECAM32(1, 14),
+	AMPERE_ECAM32(1, 15),
 };
 
 static char mcfg_oem_id[ACPI_OEM_ID_SIZE];

diff --git a/drivers/pci/ecam.c b/drivers/pci/ecam.c
@@ -164,4 +164,13 @@ struct pci_ecam_ops pci_32b_ops = {
 		.write		= pci_generic_config_write32,
 	}
 };
+
+struct pci_ecam_ops pci_32b_read_ops = {
+	.bus_shift	= 20,
+	.pci_ops	= {
+		.map_bus	= pci_ecam_map_bus,
+		.read		= pci_generic_config_read32,
+		.write		= pci_generic_config_write,
+	}
+};
 #endif
diff --git a/include/linux/pci-ecam.h b/include/linux/pci-ecam.h
@@ -57,6 +57,7 @@ extern struct pci_ecam_ops pci_thunder_ecam_ops; /* Cavium ThunderX 1.x */
 extern struct pci_ecam_ops xgene_v1_pcie_ecam_ops; /* APM X-Gene PCIe v1 */
 extern struct pci_ecam_ops xgene_v2_pcie_ecam_ops; /* APM X-Gene PCIe v2.x */
 extern struct pci_ecam_ops iproc_pcie_paxcv2_ecam_ops; /* iProc PAXCv2 */
+extern struct pci_ecam_ops pci_32b_read_ops;	/* 32-bit read accesses only */
 #endif
 
 #ifdef CONFIG_PCI_HOST_COMMON