[PATCH v1 09/24] pci: pci-uclass: Add VF BAR map support for Enhanced Allocation

[Stefan Roese]

From: Suneel Garapati <sgarapati at marvell.com>

Makes dm_pci_map_bar API available to map BAR for Virtual function
PCI devices which support Enhanced Allocation.

Signed-off-by: Suneel Garapati <sgarapati at marvell.com>
Cc: Simon Glass <sjg at chromium.org>
Cc: Bin Meng <bmeng.cn at gmail.com>

Signed-off-by: Stefan Roese <sr at denx.de>
---

Changes in v1:
- Change patch subject
- Fixed multi-line comment style
- Moved "feature" into new function which is only called, when
  CONFIG_PCI_SRIOV is enabled, so that the code is not increased in
  all cases
- Changed variable declaration to use reverse xmas tree order

 drivers/pci/pci-uclass.c | 67 +++++++++++++++++++++++++++++++++++++---
 include/pci.h            |  3 ++
 2 files changed, 65 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
index b0f2b5b77e..5e68a2e306 100644
--- a/drivers/pci/pci-uclass.c
+++ b/drivers/pci/pci-uclass.c
@@ -1368,14 +1368,55 @@ pci_addr_t dm_pci_phys_to_bus(struct udevice *dev, phys_addr_t phys_addr,
 	return bus_addr;
 }
 
+static phys_addr_t dm_pci_map_ea_virt(struct udevice *dev, int ea_off,
+				      struct pci_child_platdata *pdata)
+{
+	phys_addr_t addr = 0;
+
+	/*
+	 * In the case of a Virtual Function device using BAR
+	 * base and size, add offset for VFn BAR(1, 2, 3...n)
+	 */
+	if (pdata->is_virtfn) {
+		size_t sz;
+		u32 ea_entry;
+
+		/* MaxOffset, 1st DW */
+		dm_pci_read_config32(dev, ea_off + 8, &ea_entry);
+		sz = ea_entry & PCI_EA_FIELD_MASK;
+		/* Fill up lower 2 bits */
+		sz |= (~PCI_EA_FIELD_MASK);
+
+		if (ea_entry & PCI_EA_IS_64) {
+			/* MaxOffset 2nd DW */
+			dm_pci_read_config32(dev, ea_off + 16, &ea_entry);
+			sz |= ((u64)ea_entry) << 32;
+		}
+
+		addr = (pdata->virtid - 1) * (sz + 1);
+	}
+
+	return addr;
+}
+
 static void *dm_pci_map_ea_bar(struct udevice *dev, int bar, int flags,
-			       int ea_off)
+			       int ea_off, struct pci_child_platdata *pdata)
 {
 	int ea_cnt, i, entry_size;
 	int bar_id = (bar - PCI_BASE_ADDRESS_0) >> 2;
 	u32 ea_entry;
 	phys_addr_t addr;
 
+	if (IS_ENABLED(CONFIG_PCI_SRIOV)) {
+		/*
+		 * In the case of a Virtual Function device, device is
+		 * Physical function, so pdata will point to required VF
+		 * specific data.
+		 */
+		if (pdata->is_virtfn)
+			bar_id += PCI_EA_BEI_VF_BAR0;
+	}
+
 	/* EA capability structure header */
 	dm_pci_read_config32(dev, ea_off, &ea_entry);
 	ea_cnt = (ea_entry >> 16) & PCI_EA_NUM_ENT_MASK;
@@ -1398,6 +1439,9 @@ static void *dm_pci_map_ea_bar(struct udevice *dev, int bar, int flags,
 			addr |= ((u64)ea_entry) << 32;
 		}
 
+		if (IS_ENABLED(CONFIG_PCI_SRIOV))
+			addr += dm_pci_map_ea_virt(dev, ea_off, pdata);
+
 		/* size ignored for now */
 		return map_physmem(addr, 0, flags);
 	}
@@ -1407,20 +1451,33 @@ static void *dm_pci_map_ea_bar(struct udevice *dev, int bar, int flags,
 
 void *dm_pci_map_bar(struct udevice *dev, int bar, int flags)
 {
+	struct pci_child_platdata *pdata = dev_get_parent_platdata(dev);
+	struct udevice *udev = dev;
 	pci_addr_t pci_bus_addr;
 	u32 bar_response;
 	int ea_off;
 
+	if (IS_ENABLED(CONFIG_PCI_SRIOV)) {
+		/*
+		 * In case of Virtual Function devices, use PF udevice
+		 * as EA capability is defined in Physical Function
+		 */
+		if (pdata->is_virtfn)
+			udev = pdata->pfdev;
+	}
+
 	/*
 	 * if the function supports Enhanced Allocation use that instead of
 	 * BARs
+	 * Incase of virtual functions, pdata will help read VF BEI
+	 * and EA entry size.
 	 */
-	ea_off = dm_pci_find_capability(dev, PCI_CAP_ID_EA);
+	ea_off = dm_pci_find_capability(udev, PCI_CAP_ID_EA);
 	if (ea_off)
-		return dm_pci_map_ea_bar(dev, bar, flags, ea_off);
+		return dm_pci_map_ea_bar(udev, bar, flags, ea_off, pdata);
 
 	/* read BAR address */
-	dm_pci_read_config32(dev, bar, &bar_response);
+	dm_pci_read_config32(udev, bar, &bar_response);
 	pci_bus_addr = (pci_addr_t)(bar_response & ~0xf);
 
 	/*
@@ -1429,7 +1486,7 @@ void *dm_pci_map_bar(struct udevice *dev, int bar, int flags)
 	 * linear mapping.  In the future, this could read the BAR size
 	 * and pass that as the size if needed.
 	 */
-	return dm_pci_bus_to_virt(dev, pci_bus_addr, flags, 0, MAP_NOCACHE);
+	return dm_pci_bus_to_virt(udev, pci_bus_addr, flags, 0, MAP_NOCACHE);
 }
 
 static int _dm_pci_find_next_capability(struct udevice *dev, u8 pos, int cap)
diff --git a/include/pci.h b/include/pci.h
index 4f4b11df4a..3be642a3ef 100644
--- a/include/pci.h
+++ b/include/pci.h
@@ -465,6 +465,9 @@
 #define PCI_EA_FIRST_ENT	4	/* First EA Entry in List */
 #define  PCI_EA_ES		0x00000007 /* Entry Size */
 #define  PCI_EA_BEI		0x000000f0 /* BAR Equivalent Indicator */
+/* 9-14 map to VF BARs 0-5 respectively */
+#define  PCI_EA_BEI_VF_BAR0	9
+#define  PCI_EA_BEI_VF_BAR5	14
 /* Base, MaxOffset registers */
 /* bit 0 is reserved */
 #define  PCI_EA_IS_64		0x00000002	/* 64-bit field flag */
-- 
2.27.0