From: "Sean O. Stalley" <sean.stalley@xxxxxxxxx>
Add support for devices using Enhanced Allocation entries instead of BARs.
This patch allows the kernel to parse the EA Extended Capability structure
in PCI configspace and claim the BAR-equivalent resources.
Signed-off-by: Sean O. Stalley <sean.stalley@xxxxxxxxx>
[david.daney@xxxxxxxxxx: Added support for bridges and SRIOV]
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
---
drivers/pci/iov.c | 15 ++-
drivers/pci/pci.c | 278 ++++++++++++++++++++++++++++++++++++++++++++++++
drivers/pci/pci.h | 4 +
drivers/pci/probe.c | 42 +++++++-
drivers/pci/setup-bus.c | 3 +
include/linux/pci.h | 1 +
6 files changed, 339 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index ee0ebff..c034575 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -435,9 +435,20 @@ found:
nres = 0;
for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
+ int ea_bar = pci_ea_find_ent_with_bei(dev,
+ i + PCI_EA_BEI_VF_BAR0);
+
res = &dev->resource[i + PCI_IOV_RESOURCES];
- bar64 = __pci_read_base(dev, pci_bar_unknown, res,
- pos + PCI_SRIOV_BAR + i * 4);
+
+ if (ea_bar > 0) {
+ if (pci_ea_decode_ent(dev, ea_bar, res))
+ continue;
+ bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
+ } else {
+ bar64 = __pci_read_base(dev, pci_bar_unknown, res,
+ pos + PCI_SRIOV_BAR + i * 4);
+ }
+
if (!res->flags)
continue;
if (resource_size(res) & (PAGE_SIZE - 1)) {
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6a9a111..7c60b16 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2148,6 +2148,284 @@ void pci_pm_init(struct pci_dev *dev)
}
}
+static unsigned long pci_ea_set_flags(struct pci_dev *dev, u8 prop)
+{
+ unsigned long flags = IORESOURCE_PCI_FIXED | IORESOURCE_SIZEALIGN;
+
+ switch (prop) {
+ case PCI_EA_P_MEM:
+ case PCI_EA_P_VIRT_MEM:
+ case PCI_EA_P_BRIDGE_MEM:
+ flags |= IORESOURCE_MEM;
+ break;
+ case PCI_EA_P_MEM_PREFETCH:
+ case PCI_EA_P_VIRT_MEM_PREFETCH:
+ case PCI_EA_P_BRIDGE_MEM_PREFETCH:
+ flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
+ break;
+ case PCI_EA_P_IO:
+ case PCI_EA_P_BRIDGE_IO:
+ flags |= IORESOURCE_IO;
+ break;
+ default:
+ return 0;
+ }
+
+ return flags;
+}
+
+static struct resource *pci_ea_get_resource(struct pci_dev *dev, u8 bei)
+{
+ if (bei <= PCI_STD_RESOURCE_END)
+ return &dev->resource[bei];
+ else if (bei == PCI_EA_BEI_ROM)
+ return &dev->resource[PCI_ROM_RESOURCE];
+ else
+ return NULL;
+}
+
+int pci_ea_decode_ent(struct pci_dev *dev, int offset, struct resource *res)
+{
+ struct resource *r;
+ int i;
+ unsigned long mask;
+ int ent_offset = offset;
+ int ent_size;
+ resource_size_t start;
+ resource_size_t end;
+ unsigned long flags;
+ u32 dw0;
+ u32 base;
+ u32 max_offset;
+ 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 = ((dw0 & PCI_EA_ES) + 1) << 2;
+
+ /* Try to use primary properties, otherwise fall back to secondary */
+ flags = pci_ea_set_flags(dev, PCI_EA_PP(dw0));
+ if (!flags)
+ flags = pci_ea_set_flags(dev, PCI_EA_SP(dw0));
+
+ if (!flags) {
+ dev_err(&dev->dev, "%s: Entry EA properties not supported\n",
+ __func__);
+ 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);
+ }
+
+ dev_dbg(&dev->dev, "%s: start = %pa\n", __func__, &start);
+
+ 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);
+ }
+
+ dev_dbg(&dev->dev, "%s: end = %pa\n", __func__, &end);
+
+ 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 does not match length read\n"
+ "(Entry Size:%u Length Read:%u)\n",
+ ent_size, ent_offset - offset);
+ goto out;
+ }
+
+ res->name = pci_name(dev);
+ res->start = start;
+ res->end = end;
+ res->flags = flags;
+ mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
+ pci_bus_for_each_resource(dev->bus, r, i) {
+ if (!r)
+ continue;
+ if ((r->flags & mask) == (flags & mask) &&
+ resource_contains(r, res)) {
+ request_resource(r, res);
+ break;
+ }
+ }
+ if (!res->parent) {
+ if (flags & IORESOURCE_IO)
+ res->parent = &ioport_resource;
+ else
+ res->parent = &iomem_resource;
+ }
+ return 0;
+out:
+ return -EINVAL;
+}
+
+static int pci_ea_find_ent_with_x(struct pci_dev *dev,
+ bool (*matcher)(u32, int), int m)
+{
+ int ent_offset;
+ u8 num_ent;
+ u32 dw0;
+
+ if (!dev->ea_cap)
+ return -ENOENT;
+
+ /* determine the number of entries */
+ pci_read_config_byte(dev, dev->ea_cap + PCI_EA_NUM_ENT, &num_ent);
+ num_ent &= PCI_EA_NUM_ENT_MASK;
+
+ ent_offset = dev->ea_cap + PCI_EA_FIRST_ENT;
+ if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
+ ent_offset += 4;
+
+ while (num_ent) {
+ pci_read_config_dword(dev, ent_offset, &dw0);
+
+ if (matcher(dw0, m))
+ return ent_offset;
+
+ /* Entry size field indicates DWORDs after 1st */
+ ent_offset += ((dw0 & PCI_EA_ES) + 1) << 2;
+ num_ent--;
+ }
+ return -ENOENT;
+}
+
+static bool pci_ea_match_prop(u32 dw0, int prop)
+{
+ return PCI_EA_PP(dw0) == prop || PCI_EA_SP(dw0) == prop;
+}
+
+int pci_ea_find_ent_with_prop(struct pci_dev *dev, int prop)
+{
+ return pci_ea_find_ent_with_x(dev, pci_ea_match_prop, prop);
+}
+
+static bool pci_ea_match_bei(u32 dw0, int bei)
+{
+ return PCI_EA_BEI(dw0) == bei;
+}
+
+int pci_ea_find_ent_with_bei(struct pci_dev *dev, int bei)
+{
+ return pci_ea_find_ent_with_x(dev, pci_ea_match_bei, bei);
+}
+
+/* Read an Enhanced Allocation (EA) entry */
+static int pci_ea_read(struct pci_dev *dev, int offset)
+{
+ struct resource *res;
+ int ent_offset = offset;
+ int ent_size;
+ u32 dw0;
+
+ pci_read_config_dword(dev, ent_offset, &dw0);
+ ent_offset += 4;
+
+ /* Entry size field indicates DWORDs after 1st */
+ ent_size = ((dw0 & PCI_EA_ES) + 1) << 2;
+
+ switch (PCI_EA_PP(dw0)) {
+ case PCI_EA_P_MEM:
+ case PCI_EA_P_MEM_PREFETCH:
+ case PCI_EA_P_IO:
+ break;
+ default:
+ switch (PCI_EA_SP(dw0)) {
+ case PCI_EA_P_MEM:
+ case PCI_EA_P_MEM_PREFETCH:
+ case PCI_EA_P_IO:
+ break;
+ default:
+ goto out;
+ }
+ }
+ if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
+ goto out;
+
+ res = pci_ea_get_resource(dev, PCI_EA_BEI(dw0));
+ if (!res) {
+ dev_err(&dev->dev, "%s: Unsupported EA entry BEI\n", __func__);
+ goto out;
+ }
+
+ pci_ea_decode_ent(dev, offset, res);
+out:
+ return offset + ent_size;
+}
+
+/* Enhanced Allocation Initalization */
+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;
+
+ dev->ea_cap = ea;
+
+ /* determine the number of entries */
+ pci_read_config_byte(dev, 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 pci_add_saved_cap(struct pci_dev *pci_dev,
struct pci_cap_saved_state *new_cap)
{
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 24ba9dc..80542ac 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -78,6 +78,10 @@ bool pci_dev_keep_suspended(struct pci_dev *dev);
void pci_config_pm_runtime_get(struct pci_dev *dev);
void pci_config_pm_runtime_put(struct pci_dev *dev);
void pci_pm_init(struct pci_dev *dev);
+void pci_ea_init(struct pci_dev *dev);
+int pci_ea_decode_ent(struct pci_dev *dev, int offset, struct resource *res);
+int pci_ea_find_ent_with_prop(struct pci_dev *dev, int prop);
+int pci_ea_find_ent_with_bei(struct pci_dev *dev, int prop);
void pci_allocate_cap_save_buffers(struct pci_dev *dev);
void pci_free_cap_save_buffers(struct pci_dev *dev);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 0b2be17..52ae57d 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -338,6 +338,7 @@ static void pci_read_bridge_io(struct pci_bus *child)
unsigned long io_mask, io_granularity, base, limit;
struct pci_bus_region region;
struct resource *res;
+ int ea_ent;
io_mask = PCI_IO_RANGE_MASK;
io_granularity = 0x1000;
@@ -348,6 +349,12 @@ static void pci_read_bridge_io(struct pci_bus *child)
}
res = child->resource[0];
+ ea_ent = pci_ea_find_ent_with_prop(dev, PCI_EA_P_BRIDGE_IO);
+ if (ea_ent > 0 && !pci_ea_decode_ent(dev, ea_ent, res)) {
+ dev_dbg(&dev->dev, " bridge window %pR via EA\n", res);
+ return;
+ }
+
pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
base = (io_base_lo & io_mask) << 8;
@@ -378,8 +385,14 @@ static void pci_read_bridge_mmio(struct pci_bus *child)
unsigned long base, limit;
struct pci_bus_region region;
struct resource *res;
+ int ea_ent;
res = child->resource[1];
+ ea_ent = pci_ea_find_ent_with_prop(dev, PCI_EA_P_BRIDGE_MEM);
+ if (ea_ent > 0 && !pci_ea_decode_ent(dev, ea_ent, res)) {
+ dev_dbg(&dev->dev, " bridge window %pR via EA\n", res);
+ return;
+ }
pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
@@ -401,8 +414,14 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
pci_bus_addr_t base, limit;
struct pci_bus_region region;
struct resource *res;
+ int ea_ent;
res = child->resource[2];
+ ea_ent = pci_ea_find_ent_with_prop(dev, PCI_EA_P_BRIDGE_MEM_PREFETCH);
+ if (ea_ent > 0 && !pci_ea_decode_ent(dev, ea_ent, res)) {
+ dev_dbg(&dev->dev, " bridge window %pR via EA\n", res);
+ return;
+ }
pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
@@ -801,8 +820,24 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
primary = buses & 0xFF;
- secondary = (buses >> 8) & 0xFF;
- subordinate = (buses >> 16) & 0xFF;
+ if (dev->ea_cap) {
+ u32 sdw;
+
+ pci_read_config_dword(dev, dev->ea_cap + 4, &sdw);
+ if (sdw & 0xFF)
+ secondary = sdw & 0xFF;
+ else
+ secondary = (buses >> 8) & 0xFF;
+
+ sdw >>= 8;
+ if (sdw & 0xFF)
+ subordinate = sdw & 0xFF;
+ else
+ subordinate = (buses >> 16) & 0xFF;
+ } else {
+ secondary = (buses >> 8) & 0xFF;
+ subordinate = (buses >> 16) & 0xFF;
+ }
dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
secondary, subordinate, pass);
@@ -1598,6 +1633,9 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
static void pci_init_capabilities(struct pci_dev *dev)
{
+ /* Enhanced Allocation */
+ pci_ea_init(dev);
+
/* MSI/MSI-X list */
pci_msi_init_pci_dev(dev);
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 508cc56..1158c71 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1026,6 +1026,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
if (!b_res)
return -ENOSPC;
+ if (b_res->flags & IORESOURCE_PCI_FIXED)
+ return 0; /* Fixed from EA, we cannot change it */
+
memset(aligns, 0, sizeof(aligns));
max_order = 0;
size = 0;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index b505b50..41b85ed 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -384,6 +384,7 @@ struct pci_dev {
phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */
size_t romlen; /* Length of ROM if it's not from the BAR */
char *driver_override; /* Driver name to force a match */
+ u8 ea_cap; /* Enhanced Allocation capability offset */
};
static inline struct pci_dev *pci_physfn(struct pci_dev *dev)
--
1.9.1
--
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