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

Kishon Vijay Abraham I
2021-08-11T06:48:16Z

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@ti.com>
---
.../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