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PCI: cadence: Add MSI-X support to Endpoint driver

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Implement ->set_msix() and ->get_msix() callback functions in order
to configure MSIX capability in the PCIe endpoint controller.

Add cdns_pcie_ep_send_msix_irq() to send MSIX interrupts to Host.
cdns_pcie_ep_send_msix_irq() gets the MSIX table address (virtual
address) from "struct cdns_pcie_epf" that gets initialized in
->set_bar() call back function.

[kishon@ti.com: Re-implement MSIX support in accordance with the
 re-designed core MSI-X interfaces]
Link: https://lore.kernel.org/r/20200722110317.4744-11-kishon@ti.com
Signed-off-by: Alan Douglas <adouglas@cadence.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
This commit is contained in:
Alan Douglas 2020-07-22 16:33:12 +05:30 committed by Lorenzo Pieralisi
parent e3bca37d15
commit 3ef5d16f50
2 changed files with 117 additions and 1 deletions
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107
drivers/pci/controller/cadence/pcie-cadence-ep.c
View file

@ -51,6 +51,7 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn,
struct pci_epf_bar *epf_bar)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
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;
@ -111,6 +112,8 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn,
CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl));
cdns_pcie_writel(pcie, reg, cfg);
epf->epf_bar[bar] = epf_bar;
return 0;
}
@ -118,6 +121,7 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn,
struct pci_epf_bar *epf_bar)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie_epf *epf = &ep->epf[fn];
struct cdns_pcie *pcie = &ep->pcie;
enum pci_barno bar = epf_bar->barno;
u32 reg, cfg, b, ctrl;
@ -139,6 +143,8 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn,
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);
epf->epf_bar[bar] = NULL;
}
static int cdns_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, phys_addr_t addr,
@ -224,6 +230,50 @@ static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn)
return mme;
}
static int cdns_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no)
{
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 val, reg;
reg = cap + PCI_MSIX_FLAGS;
val = cdns_pcie_ep_fn_readw(pcie, func_no, reg);
if (!(val & PCI_MSIX_FLAGS_ENABLE))
return -EINVAL;
val &= PCI_MSIX_FLAGS_QSIZE;
return val;
}
static int cdns_pcie_ep_set_msix(struct pci_epc *epc, u8 fn, u16 interrupts,
enum pci_barno bir, u32 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 val, reg;
reg = cap + PCI_MSIX_FLAGS;
val = cdns_pcie_ep_fn_readw(pcie, fn, reg);
val &= ~PCI_MSIX_FLAGS_QSIZE;
val |= interrupts;
cdns_pcie_ep_fn_writew(pcie, fn, reg, val);
/* Set MSIX BAR and offset */
reg = cap + PCI_MSIX_TABLE;
val = offset | bir;
cdns_pcie_ep_fn_writel(pcie, fn, reg, val);
/* Set PBA BAR and offset. BAR must match MSIX BAR */
reg = cap + PCI_MSIX_PBA;
val = (offset + (interrupts * PCI_MSIX_ENTRY_SIZE)) | bir;
cdns_pcie_ep_fn_writel(pcie, fn, reg, val);
return 0;
}
static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn,
u8 intx, bool is_asserted)
{
@ -333,6 +383,51 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn,
return 0;
}
static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn,
u16 interrupt_num)
{
u32 cap = CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET;
u32 tbl_offset, msg_data, reg;
struct cdns_pcie *pcie = &ep->pcie;
struct pci_epf_msix_tbl *msix_tbl;
struct cdns_pcie_epf *epf;
u64 pci_addr_mask = 0xff;
u64 msg_addr;
u16 flags;
u8 bir;
/* 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))
return -EINVAL;
reg = cap + PCI_MSIX_TABLE;
tbl_offset = cdns_pcie_ep_fn_readl(pcie, fn, reg);
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;
/* Set the outbound region if needed. */
if (ep->irq_pci_addr != (msg_addr & ~pci_addr_mask) ||
ep->irq_pci_fn != fn) {
/* First region was reserved for IRQ writes. */
cdns_pcie_set_outbound_region(pcie, fn, 0,
false,
ep->irq_phys_addr,
msg_addr & ~pci_addr_mask,
pci_addr_mask + 1);
ep->irq_pci_addr = (msg_addr & ~pci_addr_mask);
ep->irq_pci_fn = fn;
}
writel(msg_data, ep->irq_cpu_addr + (msg_addr & pci_addr_mask));
return 0;
}
static int cdns_pcie_ep_raise_irq(struct pci_epc *epc, u8 fn,
enum pci_epc_irq_type type,
u16 interrupt_num)
@ -346,6 +441,9 @@ static int cdns_pcie_ep_raise_irq(struct pci_epc *epc, u8 fn,
case PCI_EPC_IRQ_MSI:
return cdns_pcie_ep_send_msi_irq(ep, fn, interrupt_num);
case PCI_EPC_IRQ_MSIX:
return cdns_pcie_ep_send_msix_irq(ep, fn, interrupt_num);
default:
break;
}
@ -383,7 +481,7 @@ static int cdns_pcie_ep_start(struct pci_epc *epc)
static const struct pci_epc_features cdns_pcie_epc_features = {
.linkup_notifier = false,
.msi_capable = true,
.msix_capable = false,
.msix_capable = true,
};
static const struct pci_epc_features*
@ -400,6 +498,8 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
.unmap_addr = cdns_pcie_ep_unmap_addr,
.set_msi = cdns_pcie_ep_set_msi,
.get_msi = cdns_pcie_ep_get_msi,
.set_msix = cdns_pcie_ep_set_msix,
.get_msix = cdns_pcie_ep_get_msix,
.raise_irq = cdns_pcie_ep_raise_irq,
.start = cdns_pcie_ep_start,
.get_features = cdns_pcie_ep_get_features,
@ -458,6 +558,11 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
if (of_property_read_u8(np, "max-functions", &epc->max_functions) < 0)
epc->max_functions = 1;
ep->epf = devm_kcalloc(dev, epc->max_functions, sizeof(*ep->epf),
GFP_KERNEL);
if (!ep->epf)
return -ENOMEM;
ret = pci_epc_mem_init(epc, pcie->mem_res->start,
resource_size(pcie->mem_res), PAGE_SIZE);
if (ret < 0) {

11
drivers/pci/controller/cadence/pcie-cadence.h
View file

@ -113,6 +113,7 @@
#define CDNS_PCIE_EP_FUNC_BASE(fn) (((fn) << 12) & GENMASK(19, 12))
#define CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET 0x90
#define CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET 0xb0
/*
* Root Port Registers (PCI configuration space for the root port function)
@ -302,6 +303,14 @@ struct cdns_pcie_rc {
bool avail_ib_bar[CDNS_PCIE_RP_MAX_IB];
};
/**
* struct cdns_pcie_epf - Structure to hold info about endpoint function
* @epf_bar: reference to the pci_epf_bar for the six Base Address Registers
*/
struct cdns_pcie_epf {
struct pci_epf_bar *epf_bar[PCI_STD_NUM_BARS];
};
/**
* struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
* @pcie: Cadence PCIe controller
@ -321,6 +330,7 @@ struct cdns_pcie_rc {
* @lock: spin lock to disable interrupts while modifying PCIe controller
* registers fields (RMW) accessible by both remote RC and EP to
* minimize time between read and write
* @epf: Structure to hold info about endpoint function
*/
struct cdns_pcie_ep {
struct cdns_pcie pcie;
@ -334,6 +344,7 @@ struct cdns_pcie_ep {
u8 irq_pending;
/* protect writing to PCI_STATUS while raising legacy interrupts */
spinlock_t lock;
struct cdns_pcie_epf *epf;
};