Re: [PATCH v4 02/10] PCI: dwc: Add MSI-X callbacks handler

From: Kishon Vijay Abraham I
Date: Wed Jun 20 2018 - 02:45:13 EST


Hi,

On Monday 18 June 2018 08:30 PM, Gustavo Pimentel wrote:
> Add PCIe config space capability search function.
>
> Add sysfs set/get interface to allow the change of EP MSI-X maximum number.
>
> Add EP MSI-X callback for triggering interruptions.
>
> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
> ---
> Change v1->v2:
> - Nothing changed, just to follow the patch set version.
> Change v2->v3:
> - Moved dra7xx_pcie_raise_irq() signature change to patch file #3.
> - Moved artpec6_pcie_raise_irq() signature change to patch file #3.
> - Replaced wrong return value 0 to -EINVAL.
> - Removed an else if by code refactoring.
> - Reduced the size of ioremap_nocache mapping from ep->addr_size to
> PCI_MSIX_ENTRY_SIZE.
> - Fixed a small bug. If the MSI-X vector bit has been set, the function
> would return without executing the proper unmap.
> Change v3->v4:
> - Rebased to Lorenzo's master branch v4.18-rc1.
> - Added static prefix to __dw_pcie_ep_find_next_cap function.
>
> drivers/pci/controller/dwc/pcie-designware-ep.c | 146 +++++++++++++++++++++-
> drivers/pci/controller/dwc/pcie-designware-plat.c | 4 +-
> drivers/pci/controller/dwc/pcie-designware.h | 14 ++-
> 3 files changed, 161 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 8650416..ad25654 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -40,6 +40,39 @@ void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
> __dw_pcie_ep_reset_bar(pci, bar, 0);
> }
>
> +static u8 __dw_pcie_ep_find_next_cap(struct dw_pcie *pci, u8 cap_ptr,
> + u8 cap)
> +{
> + u8 cap_id, next_cap_ptr;
> + u16 reg;
> +
> + reg = dw_pcie_readw_dbi(pci, cap_ptr);
> + next_cap_ptr = (reg & 0xff00) >> 8;
> + cap_id = (reg & 0x00ff);
> +
> + if (!next_cap_ptr || cap_id > PCI_CAP_ID_MAX)
> + return 0;
> +
> + if (cap_id == cap)
> + return cap_ptr;
> +
> + return __dw_pcie_ep_find_next_cap(pci, next_cap_ptr, cap);
> +}
> +
> +u8 dw_pcie_ep_find_capability(struct dw_pcie *pci, u8 cap)

This should be static?

Thanks
Kishon
> +{
> + u8 next_cap_ptr;
> + u16 reg;
> +
> + reg = dw_pcie_readw_dbi(pci, PCI_CAPABILITY_LIST);
> + next_cap_ptr = (reg & 0x00ff);
> +
> + if (!next_cap_ptr)
> + return 0;
> +
> + return __dw_pcie_ep_find_next_cap(pci, next_cap_ptr, cap);
> +}
> +
> static int dw_pcie_ep_write_header(struct pci_epc *epc, u8 func_no,
> struct pci_epf_header *hdr)
> {
> @@ -241,8 +274,47 @@ static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 encode_int)
> return 0;
> }
>
> +static int dw_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no)
> +{
> + struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + u32 val, reg;
> +
> + if (!ep->msix_cap)
> + return -EINVAL;
> +
> + reg = ep->msix_cap + PCI_MSIX_FLAGS;
> + val = dw_pcie_readw_dbi(pci, reg);
> + if (!(val & PCI_MSIX_FLAGS_ENABLE))
> + return -EINVAL;
> +
> + val &= PCI_MSIX_FLAGS_QSIZE;
> +
> + return val;
> +}
> +
> +static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u16 interrupts)
> +{
> + struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + u32 val, reg;
> +
> + if (!ep->msix_cap)
> + return -EINVAL;
> +
> + reg = ep->msix_cap + PCI_MSIX_FLAGS;
> + val = dw_pcie_readw_dbi(pci, reg);
> + val &= ~PCI_MSIX_FLAGS_QSIZE;
> + val |= interrupts;
> + dw_pcie_dbi_ro_wr_en(pci);
> + dw_pcie_writew_dbi(pci, reg, val);
> + dw_pcie_dbi_ro_wr_dis(pci);
> +
> + return 0;
> +}
> +
> static int dw_pcie_ep_raise_irq(struct pci_epc *epc, u8 func_no,
> - enum pci_epc_irq_type type, u8 interrupt_num)
> + enum pci_epc_irq_type type, u16 interrupt_num)
> {
> struct dw_pcie_ep *ep = epc_get_drvdata(epc);
>
> @@ -282,6 +354,8 @@ static const struct pci_epc_ops epc_ops = {
> .unmap_addr = dw_pcie_ep_unmap_addr,
> .set_msi = dw_pcie_ep_set_msi,
> .get_msi = dw_pcie_ep_get_msi,
> + .set_msix = dw_pcie_ep_set_msix,
> + .get_msix = dw_pcie_ep_get_msix,
> .raise_irq = dw_pcie_ep_raise_irq,
> .start = dw_pcie_ep_start,
> .stop = dw_pcie_ep_stop,
> @@ -322,6 +396,64 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
> return 0;
> }
>
> +int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
> + u16 interrupt_num)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + struct pci_epc *epc = ep->epc;
> + u16 tbl_offset, bir;
> + u32 bar_addr_upper, bar_addr_lower;
> + u32 msg_addr_upper, msg_addr_lower;
> + u32 reg, msg_data, vec_ctrl;
> + u64 tbl_addr, msg_addr, reg_u64;
> + void __iomem *msix_tbl;
> + int ret;
> +
> + reg = ep->msix_cap + PCI_MSIX_TABLE;
> + tbl_offset = dw_pcie_readl_dbi(pci, reg);
> + bir = (tbl_offset & PCI_MSIX_TABLE_BIR);
> + tbl_offset &= PCI_MSIX_TABLE_OFFSET;
> + tbl_offset >>= 3;
> +
> + reg = PCI_BASE_ADDRESS_0 + (4 * bir);
> + bar_addr_upper = 0;
> + bar_addr_lower = dw_pcie_readl_dbi(pci, reg);
> + reg_u64 = (bar_addr_lower & PCI_BASE_ADDRESS_MEM_TYPE_MASK);
> + if (reg_u64 == PCI_BASE_ADDRESS_MEM_TYPE_64)
> + bar_addr_upper = dw_pcie_readl_dbi(pci, reg + 4);
> +
> + tbl_addr = ((u64) bar_addr_upper) << 32 | bar_addr_lower;
> + tbl_addr += (tbl_offset + ((interrupt_num - 1) * PCI_MSIX_ENTRY_SIZE));
> + tbl_addr &= PCI_BASE_ADDRESS_MEM_MASK;
> +
> + msix_tbl = ioremap_nocache(ep->phys_base + tbl_addr,
> + PCI_MSIX_ENTRY_SIZE);
> + if (!msix_tbl)
> + return -EINVAL;
> +
> + msg_addr_lower = readl(msix_tbl + PCI_MSIX_ENTRY_LOWER_ADDR);
> + msg_addr_upper = readl(msix_tbl + PCI_MSIX_ENTRY_UPPER_ADDR);
> + msg_addr = ((u64) msg_addr_upper) << 32 | msg_addr_lower;
> + msg_data = readl(msix_tbl + PCI_MSIX_ENTRY_DATA);
> + vec_ctrl = readl(msix_tbl + PCI_MSIX_ENTRY_VECTOR_CTRL);
> +
> + iounmap(msix_tbl);
> +
> + if (vec_ctrl & PCI_MSIX_ENTRY_CTRL_MASKBIT)
> + return -EPERM;
> +
> + ret = dw_pcie_ep_map_addr(epc, func_no, ep->msix_mem_phys, msg_addr,
> + epc->mem->page_size);
> + if (ret)
> + return ret;
> +
> + writel(msg_data, ep->msix_mem);
> +
> + dw_pcie_ep_unmap_addr(epc, func_no, ep->msix_mem_phys);
> +
> + return 0;
> +}
> +
> void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
> {
> struct pci_epc *epc = ep->epc;
> @@ -329,6 +461,9 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
> pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
> epc->mem->page_size);
>
> + pci_epc_mem_free_addr(epc, ep->msix_mem_phys, ep->msix_mem,
> + epc->mem->page_size);
> +
> pci_epc_mem_exit(epc);
> }
>
> @@ -412,6 +547,15 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> dev_err(dev, "Failed to reserve memory for MSI\n");
> return -ENOMEM;
> }
> + ep->msi_cap = dw_pcie_ep_find_capability(pci, PCI_CAP_ID_MSI);
> +
> + ep->msix_mem = pci_epc_mem_alloc_addr(epc, &ep->msix_mem_phys,
> + epc->mem->page_size);
> + if (!ep->msix_mem) {
> + dev_err(dev, "Failed to reserve memory for MSI-X\n");
> + return -ENOMEM;
> + }
> + ep->msix_cap = dw_pcie_ep_find_capability(pci, PCI_CAP_ID_MSIX);
>
> epc->features = EPC_FEATURE_NO_LINKUP_NOTIFIER;
> EPC_FEATURE_SET_BAR(epc->features, BAR_0);
> diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
> index 5937fed..654dcb5 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-plat.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
> @@ -78,7 +78,7 @@ static void dw_plat_pcie_ep_init(struct dw_pcie_ep *ep)
>
> static int dw_plat_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> enum pci_epc_irq_type type,
> - u8 interrupt_num)
> + u16 interrupt_num)
> {
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
>
> @@ -88,6 +88,8 @@ static int dw_plat_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> return -EINVAL;
> case PCI_EPC_IRQ_MSI:
> return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
> + case PCI_EPC_IRQ_MSIX:
> + return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
> default:
> dev_err(pci->dev, "UNKNOWN IRQ type\n");
> }
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index bee4e25..b22c5bb 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -191,7 +191,7 @@ enum dw_pcie_as_type {
> struct dw_pcie_ep_ops {
> void (*ep_init)(struct dw_pcie_ep *ep);
> int (*raise_irq)(struct dw_pcie_ep *ep, u8 func_no,
> - enum pci_epc_irq_type type, u8 interrupt_num);
> + enum pci_epc_irq_type type, u16 interrupt_num);
> };
>
> struct dw_pcie_ep {
> @@ -208,6 +208,10 @@ struct dw_pcie_ep {
> u32 num_ob_windows;
> void __iomem *msi_mem;
> phys_addr_t msi_mem_phys;
> + void __iomem *msix_mem;
> + phys_addr_t msix_mem_phys;
> + u8 msi_cap; /* MSI capability offset */
> + u8 msix_cap; /* MSI-X capability offset */
> };
>
> struct dw_pcie_ops {
> @@ -359,6 +363,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep);
> void dw_pcie_ep_exit(struct dw_pcie_ep *ep);
> int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
> u8 interrupt_num);
> +int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
> + u16 interrupt_num);
> void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar);
> #else
> static inline void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
> @@ -380,6 +386,12 @@ static inline int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
> return 0;
> }
>
> +static inline int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
> + u16 interrupt_num)
> +{
> + return 0;
> +}
> +
> static inline void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
> {
> }
>