[PATCH v3 02/10] PCI: dwc: Add MSI-X callbacks handler

From: Gustavo Pimentel
Date: Fri Jun 01 2018 - 10:25:35 EST


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.

drivers/pci/dwc/pcie-designware-ep.c | 146 ++++++++++++++++++++++++++++++++-
drivers/pci/dwc/pcie-designware-plat.c | 4 +-
drivers/pci/dwc/pcie-designware.h | 14 +++-
3 files changed, 161 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
index 1eec441..c7f2fa9 100644
--- a/drivers/pci/dwc/pcie-designware-ep.c
+++ b/drivers/pci/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);
}

+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)
+{
+ 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);
}

@@ -410,6 +545,15 @@ 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/dwc/pcie-designware-plat.c b/drivers/pci/dwc/pcie-designware-plat.c
index 5937fed..654dcb5 100644
--- a/drivers/pci/dwc/pcie-designware-plat.c
+++ b/drivers/pci/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/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h
index bee4e25..b22c5bb 100644
--- a/drivers/pci/dwc/pcie-designware.h
+++ b/drivers/pci/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)
{
}
--
2.7.4