From 3ef5d16f50f8c32abd73e0c3bf4af690c9911cc7 Mon Sep 17 00:00:00 2001 From: Alan Douglas Date: Wed, 22 Jul 2020 16:33:12 +0530 Subject: [PATCH] PCI: cadence: Add MSI-X support to Endpoint driver 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 Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi --- drivers/pci/controller/cadence/pcie-cadence-ep.c | 107 ++++++++++++++++++++++- drivers/pci/controller/cadence/pcie-cadence.h | 11 +++ 2 files changed, 117 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 034cb3c..ec1306d 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -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) { diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h index 7c804ac..dd910a1 100644 --- a/drivers/pci/controller/cadence/pcie-cadence.h +++ b/drivers/pci/controller/cadence/pcie-cadence.h @@ -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) @@ -303,6 +304,14 @@ struct cdns_pcie_rc { }; /** + * 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 * @max_regions: maximum number of regions supported by hardware @@ -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; }; -- 2.7.4