Add three registers: doorbell_bar, doorbell_addr, and doorbell_data, along with doorbell_done. Use pci_epf_alloc_doorbell() to allocate a doorbell address space. Enable the Root Complex (RC) side driver to trigger pci-epc-test's doorbell callback handler by writing doorbell_data to the mapped doorbell_bar's address space. Set doorbell_done in the doorbell callback to indicate completion. To avoid broken compatibility, add new command COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL. Host side need send COMMAND_ENABLE_DOORBELL to map one bar's inbound address to MSI space. the command COMMAND_DISABLE_DOORBELL to recovery original inbound address mapping. Host side new driver Host side old driver EP: new driver S F EP: old driver F F S: If EP side support MSI, 'pcitest -B' return success. If EP side doesn't support MSI, the same to 'F'. F: 'pcitest -B' return failure, other case as usual. Signed-off-by: Frank Li <Frank.Li@xxxxxxx> --- change from v3 to v4 - remove revid requirement - Add command COMMAND_ENABLE_DOORBELL and COMMAND_DISABLE_DOORBELL. - call pci_epc_set_bar() to map inbound address to MSI space only at COMMAND_ENABLE_DOORBELL. --- drivers/pci/endpoint/functions/pci-epf-test.c | 104 ++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index 7c2ed6eae53ad..dcb69921497fd 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -11,12 +11,14 @@ #include <linux/dmaengine.h> #include <linux/io.h> #include <linux/module.h> +#include <linux/msi.h> #include <linux/slab.h> #include <linux/pci_ids.h> #include <linux/random.h> #include <linux/pci-epc.h> #include <linux/pci-epf.h> +#include <linux/pci-ep-msi.h> #include <linux/pci_regs.h> #define IRQ_TYPE_INTX 0 @@ -29,6 +31,8 @@ #define COMMAND_READ BIT(3) #define COMMAND_WRITE BIT(4) #define COMMAND_COPY BIT(5) +#define COMMAND_ENABLE_DOORBELL BIT(6) +#define COMMAND_DISABLE_DOORBELL BIT(7) #define STATUS_READ_SUCCESS BIT(0) #define STATUS_READ_FAIL BIT(1) @@ -39,6 +43,11 @@ #define STATUS_IRQ_RAISED BIT(6) #define STATUS_SRC_ADDR_INVALID BIT(7) #define STATUS_DST_ADDR_INVALID BIT(8) +#define STATUS_DOORBELL_SUCCESS BIT(9) +#define STATUS_DOORBELL_ENABLE_SUCCESS BIT(10) +#define STATUS_DOORBELL_ENABLE_FAIL BIT(11) +#define STATUS_DOORBELL_DISABLE_SUCCESS BIT(12) +#define STATUS_DOORBELL_DISABLE_FAIL BIT(13) #define FLAG_USE_DMA BIT(0) @@ -74,6 +83,9 @@ struct pci_epf_test_reg { u32 irq_type; u32 irq_number; u32 flags; + u32 doorbell_bar; + u32 doorbell_addr; + u32 doorbell_data; } __packed; static struct pci_epf_header test_header = { @@ -630,6 +642,60 @@ static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test, } } +static void pci_epf_enable_doorbell(struct pci_epf_test *epf_test, struct pci_epf_test_reg *reg) +{ + enum pci_barno bar = reg->doorbell_bar; + struct pci_epf *epf = epf_test->epf; + struct pci_epc *epc = epf->epc; + struct pci_epf_bar db_bar; + struct msi_msg *msg; + u64 doorbell_addr; + u32 align; + int ret; + + align = epf_test->epc_features->align; + align = align ? align : 128; + + if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) { + reg->status |= STATUS_DOORBELL_ENABLE_FAIL; + return; + } + + msg = &epf->db_msg[0].msg; + doorbell_addr = msg->address_hi; + doorbell_addr <<= 32; + doorbell_addr |= msg->address_lo; + + db_bar.phys_addr = round_down(doorbell_addr, align); + db_bar.barno = bar; + db_bar.size = epf->bar[bar].size; + db_bar.flags = epf->bar[bar].flags; + db_bar.addr = NULL; + + ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &db_bar); + if (!ret) + reg->status |= STATUS_DOORBELL_ENABLE_SUCCESS; +} + +static void pci_epf_disable_doorbell(struct pci_epf_test *epf_test, struct pci_epf_test_reg *reg) +{ + enum pci_barno bar = reg->doorbell_bar; + struct pci_epf *epf = epf_test->epf; + struct pci_epc *epc = epf->epc; + int ret; + + if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) { + reg->status |= STATUS_DOORBELL_DISABLE_FAIL; + return; + } + + ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &epf->bar[bar]); + if (ret) + reg->status |= STATUS_DOORBELL_DISABLE_FAIL; + else + reg->status |= STATUS_DOORBELL_DISABLE_SUCCESS; +} + static void pci_epf_test_cmd_handler(struct work_struct *work) { u32 command; @@ -676,6 +742,14 @@ static void pci_epf_test_cmd_handler(struct work_struct *work) pci_epf_test_copy(epf_test, reg); pci_epf_test_raise_irq(epf_test, reg); break; + case COMMAND_ENABLE_DOORBELL: + pci_epf_enable_doorbell(epf_test, reg); + pci_epf_test_raise_irq(epf_test, reg); + break; + case COMMAND_DISABLE_DOORBELL: + pci_epf_disable_doorbell(epf_test, reg); + pci_epf_test_raise_irq(epf_test, reg); + break; default: dev_err(dev, "Invalid command 0x%x\n", command); break; @@ -810,11 +884,24 @@ static int pci_epf_test_link_down(struct pci_epf *epf) return 0; } +static int pci_epf_test_doorbell(struct pci_epf *epf, int index) +{ + struct pci_epf_test *epf_test = epf_get_drvdata(epf); + enum pci_barno test_reg_bar = epf_test->test_reg_bar; + struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar]; + + reg->status |= STATUS_DOORBELL_SUCCESS; + pci_epf_test_raise_irq(epf_test, reg); + + return 0; +} + static const struct pci_epc_event_ops pci_epf_test_event_ops = { .epc_init = pci_epf_test_epc_init, .epc_deinit = pci_epf_test_epc_deinit, .link_up = pci_epf_test_link_up, .link_down = pci_epf_test_link_down, + .doorbell = pci_epf_test_doorbell, }; static int pci_epf_test_alloc_space(struct pci_epf *epf) @@ -909,6 +996,23 @@ static int pci_epf_test_bind(struct pci_epf *epf) if (ret) return ret; + ret = pci_epf_alloc_doorbell(epf, 1); + if (!ret) { + struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar]; + struct msi_msg *msg = &epf->db_msg[0].msg; + u32 align = epc_features->align; + u64 doorbell_addr; + + align = align ? align : 128; + doorbell_addr = msg->address_hi; + doorbell_addr <<= 32; + doorbell_addr |= msg->address_lo; + + reg->doorbell_addr = doorbell_addr & (align - 1); + reg->doorbell_data = msg->data; + reg->doorbell_bar = pci_epc_get_next_free_bar(epc_features, test_reg_bar + 1); + } + return 0; } -- 2.34.1