[PATCH 6/7] PCI: cadence: Add support to configure virtual functions

From: Kishon Vijay Abraham I
Date: Tue Dec 31 2019 - 06:34:41 EST


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 | 201 ++++++++++++++++--
drivers/pci/controller/cadence/pcie-cadence.h | 7 +
2 files changed, 189 insertions(+), 19 deletions(-)

diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
index 673224e2e314..78c25635c4e1 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
@@ -20,7 +20,18 @@ 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_dbg(&epc->dev, "Only Virtual Function #1 has deviceID\n");
+ return 0;
+ } 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);
@@ -51,12 +62,14 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, u8 vfn,
struct pci_epf_bar *epf_bar)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+ u32 cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
struct cdns_pcie_epf *epf = &ep->epf[fn];
struct cdns_pcie *pcie = &ep->pcie;
dma_addr_t bar_phys = epf_bar->phys_addr;
enum pci_barno bar = epf_bar->barno;
int flags = epf_bar->flags;
u32 addr0, addr1, reg, cfg, b, aperture, ctrl;
+ u32 first_vf_offset, stride;
u64 sz;

/* BAR size is 2^(aperture + 7) */
@@ -92,19 +105,39 @@ 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);
+
+ if (vfn == 1) {
+ if (bar < BAR_4) {
+ reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG0(fn);
+ b = bar;
+ } else {
+ reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG1(fn);
+ b = bar - BAR_4;
+ }
+ } else {
+ if (bar < BAR_4) {
+ reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
+ b = bar;
+ } else {
+ reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
+ b = bar - BAR_4;
+ }
+ }
+
+ if (vfn > 0) {
+ 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);
+ epf = &epf->epf[vfn - 1];
+ }
+
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 (bar < BAR_4) {
- reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
- b = bar;
- } else {
- reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
- b = 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));
@@ -121,17 +154,38 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn, u8 vfn,
struct pci_epf_bar *epf_bar)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+ u32 cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
struct cdns_pcie_epf *epf = &ep->epf[fn];
struct cdns_pcie *pcie = &ep->pcie;
enum pci_barno bar = epf_bar->barno;
+ u32 first_vf_offset, stride;
u32 reg, cfg, b, ctrl;

- if (bar < BAR_4) {
- reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
- b = bar;
+ if (vfn == 1) {
+ if (bar < BAR_4) {
+ reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG0(fn);
+ b = bar;
+ } else {
+ reg = CDNS_PCIE_LM_EP_VFUNC_BAR_CFG1(fn);
+ b = bar - BAR_4;
+ }
} else {
- reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
- b = bar - BAR_4;
+ if (bar < BAR_4) {
+ reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
+ b = bar;
+ } else {
+ reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
+ b = bar - BAR_4;
+ }
+ }
+
+ if (vfn > 0) {
+ 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);
+ epf = &epf->epf[vfn - 1];
}

ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
@@ -152,8 +206,18 @@ static int cdns_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, u8 vfn,
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
+ u32 cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
+ u32 first_vf_offset, stride;
u32 r;

+ if (vfn > 0) {
+ 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);
+ }
+
r = find_first_zero_bit(&ep->ob_region_map,
sizeof(ep->ob_region_map) * BITS_PER_LONG);
if (r >= ep->max_regions - 1) {
@@ -193,9 +257,19 @@ static int cdns_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn, u8 mmc)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
+ u32 first_vf_offset, stride;
u16 flags;

+ if (vfn > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ fn = fn + first_vf_offset + ((vfn - 1) * stride);
+ }
+
/*
* Set the Multiple Message Capable bitfield into the Message Control
* register.
@@ -213,9 +287,19 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
+ u32 first_vf_offset, stride;
u16 flags, mme;

+ if (vfn > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ fn = fn + first_vf_offset + ((vfn - 1) * stride);
+ }
+
/* 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))
@@ -232,11 +316,21 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn)

static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no)
{
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
+ u32 first_vf_offset, stride;
u32 val, reg;

+ if (vfunc_no > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, func_no, sriov_cap
+ + PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, func_no, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ func_no = func_no + first_vf_offset + ((vfunc_no - 1) * stride);
+ }
+
reg = cap + PCI_MSIX_FLAGS;
val = cdns_pcie_ep_fn_readw(pcie, func_no, reg);
if (!(val & PCI_MSIX_FLAGS_ENABLE))
@@ -251,11 +345,21 @@ static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u8 vfn,
u16 interrupts, enum pci_barno bir,
u32 offset)
{
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
+ u32 first_vf_offset, stride;
u32 val, reg;

+ if (vfn > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ fn = fn + first_vf_offset + ((vfn - 1) * stride);
+ }
+
reg = cap + PCI_MSIX_FLAGS;
val = cdns_pcie_ep_fn_readw(pcie, fn, reg);
val &= ~PCI_MSIX_FLAGS_QSIZE;
@@ -275,8 +379,8 @@ 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;
u32 offset;
@@ -337,10 +441,20 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
u8 interrupt_num)
{
struct cdns_pcie *pcie = &ep->pcie;
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
u16 flags, mme, data, data_mask;
u8 msi_count;
u64 pci_addr, pci_addr_mask = 0xff;
+ u32 first_vf_offset, stride;
+
+ if (vfn > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ fn = fn + first_vf_offset + ((vfn - 1) * stride);
+ }

/* Check whether the MSI feature has been enabled by the PCI host. */
flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
@@ -381,13 +495,15 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
return 0;
}

-static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn,
+static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
u16 interrupt_num)
{
+ u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
u32 tbl_offset, msg_data, reg, vec_ctrl;
struct cdns_pcie *pcie = &ep->pcie;
struct pci_epf_msix_tbl *msix_tbl;
+ u32 first_vf_offset, stride;
struct pci_epf_bar *epf_bar;
struct cdns_pcie_epf *epf;
u64 pci_addr_mask = 0xff;
@@ -395,6 +511,17 @@ static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn,
u16 flags;
u8 bir;

+ epf = &ep->epf[fn];
+
+ if (vfn > 0) {
+ first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_OFFSET);
+ stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+ PCI_SRIOV_VF_STRIDE);
+ fn = fn + first_vf_offset + ((vfn - 1) * stride);
+ epf = &epf->epf[vfn - 1];
+ }
+
/* 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))
@@ -405,7 +532,6 @@ static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn,
bir = tbl_offset & PCI_MSIX_TABLE_BIR;
tbl_offset &= PCI_MSIX_TABLE_OFFSET;

- epf = &ep->epf[fn];
epf_bar = epf->epf_bar[bir];
msix_tbl = epf_bar->addr;
msix_tbl = (struct pci_epf_msix_tbl *)((char *)msix_tbl + tbl_offset);
@@ -436,16 +562,22 @@ 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, 0);

case PCI_EPC_IRQ_MSI:
return cdns_pcie_ep_send_msi_irq(ep, fn, vfn, interrupt_num);

case PCI_EPC_IRQ_MSIX:
- return cdns_pcie_ep_send_msix_irq(ep, fn, interrupt_num);
+ return cdns_pcie_ep_send_msix_irq(ep, fn, vfn, interrupt_num);

default:
break;
@@ -481,6 +613,13 @@ 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,
@@ -490,7 +629,10 @@ 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 = {
@@ -515,9 +657,11 @@ 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;

@@ -566,6 +710,25 @@ 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_u16_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));
if (ret < 0) {
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 2f688b9d205b..285d3c5a715b 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -50,6 +50,10 @@
(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_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) \
@@ -100,6 +104,7 @@

#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)
@@ -285,9 +290,11 @@ 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