Some PCI devices have their base addresses not defined in the BARs,
but instead have them defined in Enhanced Allocation structures.
Add support for these Enhanced Allocation structures, taken directly
from the Linux Kernel.
Motivation for adding this is the LS1028a SoC which uses Enhanced
Allocation for the Ethernet Subsystem which comes as an integrated
Endpoint Root Complex.
Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
---
drivers/pci/pci.c | 186 +++++++++++++++++++++++++++++++++++++++
include/linux/pci_regs.h | 49 ++++++++++-
2 files changed, 234 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 0211fc0081..a3e7e70871 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4,6 +4,7 @@
#include <common.h>
#include <linux/sizes.h>
#include <linux/pci.h>
+#include <linux/bitfield.h>
static unsigned int pci_scan_bus(struct pci_bus *bus);
@@ -152,6 +153,189 @@ static u32 pci_size(u32 base, u32 maxbase, u32 mask)
return size + 1;
}
+static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)
+{
+ unsigned long flags = IORESOURCE_PCI_FIXED;
+
+ switch (prop) {
+ case PCI_EA_P_MEM:
+ case PCI_EA_P_VF_MEM:
+ flags |= IORESOURCE_MEM;
+ break;
+ case PCI_EA_P_MEM_PREFETCH:
+ case PCI_EA_P_VF_MEM_PREFETCH:
+ flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
+ break;
+ case PCI_EA_P_IO:
+ flags |= IORESOURCE_IO;
+ break;
+ default:
+ return 0;
+ }
+
+ return flags;
+}
+
+static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei,
+ u8 prop)
+{
+ if (bei <= PCI_EA_BEI_BAR5 && prop <= PCI_EA_P_IO)
+ return &dev->resource[bei];
+ else if (bei == PCI_EA_BEI_ROM)
+ return &dev->resource[PCI_ROM_RESOURCE];
+ else
+ return NULL;
+}
+
+/* Read an Enhanced Allocation (EA) entry */
+static int pci_ea_read(struct pci_dev *dev, int offset)
+{
+ struct resource *res;
+ int ent_size, ent_offset = offset;
+ resource_size_t start, end;
+ unsigned long flags;
+ u32 dw0, bei, base, max_offset;
+ u8 prop;
+ bool support_64 = (sizeof(resource_size_t) >= 8);
+
+ pci_read_config_dword(dev, ent_offset, &dw0);
+ ent_offset += 4;
+
+ /* Entry size field indicates DWORDs after 1st */
+ ent_size = (FIELD_GET(PCI_EA_ES, dw0) + 1) << 2;
+
+ if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
+ goto out;
+
+ bei = FIELD_GET(PCI_EA_BEI, dw0);
+ prop = FIELD_GET(PCI_EA_PP, dw0);
+
+ /*
+ * If the Property is in the reserved range, try the Secondary
+ * Property instead.
+ */
+ if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
+ prop = FIELD_GET(PCI_EA_SP, dw0);
+ if (prop > PCI_EA_P_BRIDGE_IO)
+ goto out;
+
+ res = pci_ea_get_resource(dev, bei, prop);
+ if (!res) {
+ dev_dbg(&dev->dev, "Unsupported EA entry BEI: %u\n", bei);
+ goto out;
+ }
+
+ flags = pci_ea_flags(dev, prop);
+ if (!flags) {
+ dev_err(&dev->dev, "Unsupported EA properties: %#x\n", prop);
+ goto out;
+ }
+
+ /* Read Base */
+ pci_read_config_dword(dev, ent_offset, &base);
+ start = (base & PCI_EA_FIELD_MASK);
+ ent_offset += 4;
+
+ /* Read MaxOffset */
+ pci_read_config_dword(dev, ent_offset, &max_offset);
+ ent_offset += 4;
+
+ /* Read Base MSBs (if 64-bit entry) */
+ if (base & PCI_EA_IS_64) {
+ u32 base_upper;
+
+ pci_read_config_dword(dev, ent_offset, &base_upper);
+ ent_offset += 4;
+
+ flags |= IORESOURCE_MEM_64;
+
+ /* entry starts above 32-bit boundary, can't use */
+ if (!support_64 && base_upper)
+ goto out;
+
+ if (support_64)
+ start |= ((u64)base_upper << 32);
+ }
+
+ end = start + (max_offset | 0x03);
+
+ /* Read MaxOffset MSBs (if 64-bit entry) */
+ if (max_offset & PCI_EA_IS_64) {
+ u32 max_offset_upper;
+
+ pci_read_config_dword(dev, ent_offset, &max_offset_upper);
+ ent_offset += 4;
+
+ flags |= IORESOURCE_MEM_64;
+
+ /* entry too big, can't use */
+ if (!support_64 && max_offset_upper)
+ goto out;
+
+ if (support_64)
+ end += ((u64)max_offset_upper << 32);
+ }
+
+ if (end < start) {
+ dev_err(&dev->dev, "EA Entry crosses address boundary\n");
+ goto out;
+ }
+
+ if (ent_size != ent_offset - offset) {
+ dev_err(&dev->dev, "EA Entry Size (%d) does not match length read (%d)\n",
+ ent_size, ent_offset - offset);
+ goto out;
+ }
+
+ res->start = start;
+ res->end = end;
+ res->flags = flags;
+
+ if (bei <= PCI_EA_BEI_BAR5)
+ dev_dbg(&dev->dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
+ bei, res, prop);
+ else if (bei == PCI_EA_BEI_ROM)
+ dev_dbg(&dev->dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
+ res, prop);
+ else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
+ dev_dbg(&dev->dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
+ bei - PCI_EA_BEI_VF_BAR0, res, prop);
+ else
+ dev_dbg(&dev->dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
+ bei, res, prop);
+
+out:
+ return offset + ent_size;
+}
+
+/* Enhanced Allocation Initialization */
+static void pci_ea_init(struct pci_dev *dev)
+{
+ int ea;
+ u8 num_ent;
+ int offset;
+ int i;
+
+ /* find PCI EA capability in list */
+ ea = pci_find_capability(dev, PCI_CAP_ID_EA);
+ if (!ea)
+ return;
+
+ /* determine the number of entries */
+ pci_bus_read_config_byte(dev->bus, dev->devfn, ea + PCI_EA_NUM_ENT,
+ &num_ent);
+ num_ent &= PCI_EA_NUM_ENT_MASK;
+
+ offset = ea + PCI_EA_FIRST_ENT;
+
+ /* Skip DWORD 2 for type 1 functions */
+ if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
+ offset += 4;
+
+ /* parse each EA entry */
+ for (i = 0; i < num_ent; ++i)
+ offset = pci_ea_read(dev, offset);
+}
static void setup_device(struct pci_dev *dev, int max_bar)
{
@@ -251,6 +435,8 @@ static void setup_device(struct pci_dev *dev, int max_bar)
}
}
+ pci_ea_init(dev);
+
pci_fixup_device(pci_fixup_header, dev);
if (pcibios_assign_all_busses())
diff --git a/include/linux/pci_regs.h b/include/linux/pci_regs.h
index 631f218229..8d71914f75 100644
--- a/include/linux/pci_regs.h
+++ b/include/linux/pci_regs.h
@@ -219,7 +219,8 @@
#define PCI_CAP_ID_MSIX 0x11 /* MSI-X */
#define PCI_CAP_ID_SATA 0x12 /* SATA Data/Index Conf. */
#define PCI_CAP_ID_AF 0x13 /* PCI Advanced Features */
-#define PCI_CAP_ID_MAX PCI_CAP_ID_AF
+#define PCI_CAP_ID_EA 0x14 /* PCI Enhanced Allocation */
+#define PCI_CAP_ID_MAX PCI_CAP_ID_EA
#define PCI_CAP_LIST_NEXT 1 /* Next capability in the list */
#define PCI_CAP_FLAGS 2 /* Capability defined flags (16 bits) */
#define PCI_CAP_SIZEOF 4
@@ -355,6 +356,52 @@
#define PCI_AF_STATUS_TP 0x01
#define PCI_CAP_AF_SIZEOF 6 /* size of AF registers */
+/* PCI Enhanced Allocation registers */
+
+#define PCI_EA_NUM_ENT 2 /* Number of Capability Entries */
+#define PCI_EA_NUM_ENT_MASK 0x3f /* Num Entries Mask */
+#define PCI_EA_FIRST_ENT 4 /* First EA Entry in List */
+#define PCI_EA_FIRST_ENT_BRIDGE 8 /* First EA Entry for Bridges */
+#define PCI_EA_ES 0x00000007 /* Entry Size */
+#define PCI_EA_BEI 0x000000f0 /* BAR Equivalent Indicator */
+
+/* EA fixed Secondary and Subordinate bus numbers for Bridge */
+#define PCI_EA_SEC_BUS_MASK 0xff
+#define PCI_EA_SUB_BUS_MASK 0xff00
+#define PCI_EA_SUB_BUS_SHIFT 8
+
+/* 0-5 map to BARs 0-5 respectively */
+#define PCI_EA_BEI_BAR0 0
+#define PCI_EA_BEI_BAR5 5
+#define PCI_EA_BEI_BRIDGE 6 /* Resource behind bridge */
+#define PCI_EA_BEI_ENI 7 /* Equivalent Not Indicated */
+#define PCI_EA_BEI_ROM 8 /* Expansion ROM */
+/* 9-14 map to VF BARs 0-5 respectively */
+#define PCI_EA_BEI_VF_BAR0 9
+#define PCI_EA_BEI_VF_BAR5 14
+#define PCI_EA_BEI_RESERVED 15 /* Reserved - Treat like ENI */
+#define PCI_EA_PP 0x0000ff00 /* Primary Properties */
+#define PCI_EA_SP 0x00ff0000 /* Secondary Properties */
+#define PCI_EA_P_MEM 0x00 /* Non-Prefetch Memory */
+#define PCI_EA_P_MEM_PREFETCH 0x01 /* Prefetchable Memory */
+#define PCI_EA_P_IO 0x02 /* I/O Space */
+#define PCI_EA_P_VF_MEM_PREFETCH 0x03 /* VF Prefetchable Memory */
+#define PCI_EA_P_VF_MEM 0x04 /* VF Non-Prefetch Memory */
+#define PCI_EA_P_BRIDGE_MEM 0x05 /* Bridge Non-Prefetch Memory */
+#define PCI_EA_P_BRIDGE_MEM_PREFETCH 0x06 /* Bridge Prefetchable Memory */
+#define PCI_EA_P_BRIDGE_IO 0x07 /* Bridge I/O Space */
+/* 0x08-0xfc reserved */
+#define PCI_EA_P_MEM_RESERVED 0xfd /* Reserved Memory */
+#define PCI_EA_P_IO_RESERVED 0xfe /* Reserved I/O Space */
+#define PCI_EA_P_UNAVAILABLE 0xff /* Entry Unavailable */
+#define PCI_EA_WRITABLE 0x40000000 /* Writable: 1 = RW, 0 = HwInit */
+#define PCI_EA_ENABLE 0x80000000 /* Enable for this entry */
+#define PCI_EA_BASE 4 /* Base Address Offset */
+#define PCI_EA_MAX_OFFSET 8 /* MaxOffset (resource length) */
+/* bit 0 is reserved */
+#define PCI_EA_IS_64 0x00000002 /* 64-bit field flag */
+#define PCI_EA_FIELD_MASK 0xfffffffc /* For Base & Max Offset */
+
/* PCI-X registers (Type 0 (non-bridge) devices) */
#define PCI_X_CMD 2 /* Modes & Features */
--
2.39.2
