[PATCH v8 6/8] PCI: cadence: Add support to configure virtual functions

[Kishon Vijay Abraham I]

Now that support for SR-IOV is added in PCIe endpoint core, add support
to configure virtual functions in the Cadence PCIe EP driver.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
 .../pci/controller/cadence/pcie-cadence-ep.c  | 136 +++++++++++++++---
 drivers/pci/controller/cadence/pcie-cadence.h |   9 ++
 2 files changed, 125 insertions(+), 20 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index f337f0842400..443dd06dfcfc 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -16,11 +16,37 @@
 #define CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE		0x1
 #define CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY	0x3
 
+static u8 cdns_pcie_get_fn_from_vfn(struct cdns_pcie *pcie, u8 fn, u8 vfn)
+{
+	u32 cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
+	u32 first_vf_offset, stride;
+
+	if (vfn == 0)
+		return fn;
+
+	first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_SRIOV_VF_OFFSET);
+	stride = cdns_pcie_ep_fn_readw(pcie, fn, cap +  PCI_SRIOV_VF_STRIDE);
+	fn = fn + first_vf_offset + ((vfn - 1) * stride);
+
+	return fn;
+}
+
 static int cdns_pcie_ep_write_header(struct pci_epc *epc, u8 fn, u8 vfn,
 				     struct pci_epf_header *hdr)
 {
 	struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+	u32 cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
 	struct cdns_pcie *pcie = &ep->pcie;
+	u32 reg;
+
+	if (vfn > 1) {
+		dev_err(&epc->dev, "Only Virtual Function #1 has deviceID\n");
+		return -EINVAL;
+	} else if (vfn == 1) {
+		reg = cap + PCI_SRIOV_VF_DID;
+		cdns_pcie_ep_fn_writew(pcie, fn, reg, hdr->deviceid);
+		return 0;
+	}
 
 	cdns_pcie_ep_fn_writew(pcie, fn, PCI_DEVICE_ID, hdr->deviceid);
 	cdns_pcie_ep_fn_writeb(pcie, fn, PCI_REVISION_ID, hdr->revid);
@@ -92,21 +118,29 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, u8 vfn,
 
 	addr0 = lower_32_bits(bar_phys);
 	addr1 = upper_32_bits(bar_phys);
-	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar),
-			 addr0);
-	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar),
-			 addr1);
 
 	reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG(bar, fn);
+	if (vfn == 1)
+		reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG(bar, fn);
 	b = (bar < BAR_4) ? bar : bar - BAR_4;
 
-	cfg = cdns_pcie_readl(pcie, reg);
-	cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
-		 CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
-	cfg |= (CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE(b, aperture) |
-		CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl));
-	cdns_pcie_writel(pcie, reg, cfg);
+	if (vfn == 0 || vfn == 1) {
+		cfg = cdns_pcie_readl(pcie, reg);
+		cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
+			 CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
+		cfg |= (CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE(b, aperture) |
+			CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl));
+		cdns_pcie_writel(pcie, reg, cfg);
+	}
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar),
+			 addr0);
+	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar),
+			 addr1);
+
+	if (vfn > 0)
+		epf = &epf->epf[vfn - 1];
 	epf->epf_bar[bar] = epf_bar;
 
 	return 0;
@@ -122,18 +156,25 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn, u8 vfn,
 	u32 reg, cfg, b, ctrl;
 
 	reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG(bar, fn);
+	if (vfn == 1)
+		reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG(bar, fn);
 	b = (bar < BAR_4) ? bar : bar - BAR_4;
 
-	ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
-	cfg = cdns_pcie_readl(pcie, reg);
-	cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
-		 CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
-	cfg |= CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl);
-	cdns_pcie_writel(pcie, reg, cfg);
+	if (vfn == 0 || vfn == 1) {
+		ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
+		cfg = cdns_pcie_readl(pcie, reg);
+		cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
+			 CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
+		cfg |= CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl);
+		cdns_pcie_writel(pcie, reg, cfg);
+	}
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar), 0);
 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar), 0);
 
+	if (vfn > 0)
+		epf = &epf->epf[vfn - 1];
 	epf->epf_bar[bar] = NULL;
 }
 
@@ -151,6 +192,7 @@ static int cdns_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, u8 vfn,
 		return -EINVAL;
 	}
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
 	cdns_pcie_set_outbound_region(pcie, 0, fn, r, false, addr, pci_addr, size);
 
 	set_bit(r, &ep->ob_region_map);
@@ -186,6 +228,8 @@ static int cdns_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, u8 mmc)
 	u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
 	u16 flags;
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	/*
 	 * Set the Multiple Message Capable bitfield into the Message Control
 	 * register.
@@ -206,6 +250,8 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn)
 	u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
 	u16 flags, mme;
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	/* Validate that the MSI feature is actually enabled. */
 	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
 	if (!(flags & PCI_MSI_FLAGS_ENABLE))
@@ -227,6 +273,8 @@ static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no)
 	u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
 	u32 val, reg;
 
+	func_no = cdns_pcie_get_fn_from_vfn(pcie, func_no, vfunc_no);
+
 	reg = cap + PCI_MSIX_FLAGS;
 	val = cdns_pcie_ep_fn_readw(pcie, func_no, reg);
 	if (!(val & PCI_MSIX_FLAGS_ENABLE))
@@ -246,6 +294,8 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn,
 	u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
 	u32 val, reg;
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	reg = cap + PCI_MSIX_FLAGS;
 	val = cdns_pcie_ep_fn_readw(pcie, fn, reg);
 	val &= ~PCI_MSIX_FLAGS_QSIZE;
@@ -265,8 +315,8 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn,
 	return 0;
 }
 
-static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn,
-				     u8 intx, bool is_asserted)
+static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn, u8 intx,
+				     bool is_asserted)
 {
 	struct cdns_pcie *pcie = &ep->pcie;
 	unsigned long flags;
@@ -335,6 +385,8 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
 	u8 msi_count;
 	u64 pci_addr, pci_addr_mask = 0xff;
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	/* Check whether the MSI feature has been enabled by the PCI host. */
 	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
 	if (!(flags & PCI_MSI_FLAGS_ENABLE))
@@ -388,6 +440,8 @@ static int cdns_pcie_ep_map_msi_irq(struct pci_epc *epc, u8 fn, u8 vfn,
 	int ret;
 	int i;
 
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	/* Check whether the MSI feature has been enabled by the PCI host. */
 	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
 	if (!(flags & PCI_MSI_FLAGS_ENABLE))
@@ -438,6 +492,12 @@ static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
 	u16 flags;
 	u8 bir;
 
+	epf = &ep->epf[fn];
+	if (vfn > 0)
+		epf = &epf->epf[vfn - 1];
+
+	fn = cdns_pcie_get_fn_from_vfn(pcie, fn, vfn);
+
 	/* Check whether the MSI-X feature has been enabled by the PCI host. */
 	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSIX_FLAGS);
 	if (!(flags & PCI_MSIX_FLAGS_ENABLE))
@@ -448,7 +508,6 @@ static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
 	bir = tbl_offset & PCI_MSIX_TABLE_BIR;
 	tbl_offset &= PCI_MSIX_TABLE_OFFSET;
 
-	epf = &ep->epf[fn];
 	msix_tbl = epf->epf_bar[bir]->addr + tbl_offset;
 	msg_addr = msix_tbl[(interrupt_num - 1)].msg_addr;
 	msg_data = msix_tbl[(interrupt_num - 1)].msg_data;
@@ -475,9 +534,15 @@ static int cdns_pcie_ep_raise_irq(struct pci_epc *epc, u8 fn, u8 vfn,
 				  u16 interrupt_num)
 {
 	struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+	struct cdns_pcie *pcie = &ep->pcie;
+	struct device *dev = pcie->dev;
 
 	switch (type) {
 	case PCI_EPC_IRQ_LEGACY:
+		if (vfn > 0) {
+			dev_err(dev, "Cannot raise legacy interrupts for VF\n");
+			return -EINVAL;
+		}
 		return cdns_pcie_ep_send_legacy_irq(ep, fn, vfn, 0);
 
 	case PCI_EPC_IRQ_MSI:
@@ -515,6 +580,13 @@ static int cdns_pcie_ep_start(struct pci_epc *epc)
 	return 0;
 }
 
+static const struct pci_epc_features cdns_pcie_epc_vf_features = {
+	.linkup_notifier = false,
+	.msi_capable = true,
+	.msix_capable = true,
+	.align = 65536,
+};
+
 static const struct pci_epc_features cdns_pcie_epc_features = {
 	.linkup_notifier = false,
 	.msi_capable = true,
@@ -525,7 +597,10 @@ static const struct pci_epc_features cdns_pcie_epc_features = {
 static const struct pci_epc_features*
 cdns_pcie_ep_get_features(struct pci_epc *epc, u8 func_no, u8 vfunc_no)
 {
-	return &cdns_pcie_epc_features;
+	if (!vfunc_no)
+		return &cdns_pcie_epc_features;
+
+	return &cdns_pcie_epc_vf_features;
 }
 
 static const struct pci_epc_ops cdns_pcie_epc_ops = {
@@ -551,9 +626,11 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
 	struct cdns_pcie *pcie = &ep->pcie;
+	struct cdns_pcie_epf *epf;
 	struct resource *res;
 	struct pci_epc *epc;
 	int ret;
+	int i;
 
 	pcie->is_rc = false;
 
@@ -598,6 +675,25 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
 	if (!ep->epf)
 		return -ENOMEM;
 
+	epc->max_vfs = devm_kcalloc(dev, epc->max_functions,
+				    sizeof(*epc->max_vfs), GFP_KERNEL);
+	if (!epc->max_vfs)
+		return -ENOMEM;
+
+	ret = of_property_read_u8_array(np, "max-virtual-functions",
+					epc->max_vfs, epc->max_functions);
+	if (ret == 0) {
+		for (i = 0; i < epc->max_functions; i++) {
+			epf = &ep->epf[i];
+			if (epc->max_vfs[i] == 0)
+				continue;
+			epf->epf = devm_kcalloc(dev, epc->max_vfs[i],
+						sizeof(*ep->epf), GFP_KERNEL);
+			if (!epf->epf)
+				return -ENOMEM;
+		}
+	}
+
 	ret = pci_epc_mem_init(epc, pcie->mem_res->start,
 			       resource_size(pcie->mem_res), PAGE_SIZE);
 	if (ret < 0) {
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index d5b1fcf2c39d..b72de578b996 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -52,6 +52,12 @@
 	(CDNS_PCIE_LM_BASE + 0x0240 + (fn) * 0x0008)
 #define CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn) \
 	(CDNS_PCIE_LM_BASE + 0x0244 + (fn) * 0x0008)
+#define CDNS_PCIE_LM_EP_VFUNC_BAR_CFG(bar, fn) \
+	(((bar) < 4) ? CDNS_PCIE_LM_EP_VFUNC_BAR_CFG0(fn) : CDNS_PCIE_LM_EP_VFUNC_BAR_CFG1(fn))
+#define CDNS_PCIE_LM_EP_VFUNC_BAR_CFG0(fn) \
+	(CDNS_PCIE_LM_BASE + 0x0280 + (fn) * 0x0008)
+#define CDNS_PCIE_LM_EP_VFUNC_BAR_CFG1(fn) \
+	(CDNS_PCIE_LM_BASE + 0x0284 + (fn) * 0x0008)
 #define  CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) \
 	(GENMASK(4, 0) << ((b) * 8))
 #define  CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE(b, a) \
@@ -116,6 +122,7 @@
 
 #define CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET	0x90
 #define CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET	0xb0
+#define CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET	0x200
 
 /*
  * Root Port Registers (PCI configuration space for the root port function)
@@ -310,9 +317,11 @@ struct cdns_pcie_rc {
 
 /**
  * struct cdns_pcie_epf - Structure to hold info about endpoint function
+ * @epf: Info about virtual functions attached to the physical function
  * @epf_bar: reference to the pci_epf_bar for the six Base Address Registers
  */
 struct cdns_pcie_epf {
+	struct cdns_pcie_epf *epf;
 	struct pci_epf_bar *epf_bar[PCI_STD_NUM_BARS];
 };
 
-- 
2.17.1