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.
Tested-by: Niklas Cassel <cassel@xxxxxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
Change from v5 to v6
- rename doorbell_addr to doorbell_offset
Chagne from v4 to v5
- Add doorbell free at unbind function.
- Move msi irq handler to here to more complex user case, such as differece
doorbell can use difference handler function.
- Add Niklas's code to handle fixed bar's case. If need add your signed-off
tag or co-developer tag, please let me know.
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 | 129 ++++++++++++++++++++++++++
1 file changed, 129 insertions(+)
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index ef6677f34116e..2d05ab5e4ac6a 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_offset;
+ u32 doorbell_data;
} __packed;
static struct pci_epf_header test_header = {
@@ -642,6 +654,63 @@ 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 (epf_test->epc_features->bar[bar].type == BAR_FIXED)
+ align = max(epf_test->epc_features->bar[bar].fixed_size, align);
+
+ 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;
@@ -688,6 +757,14 @@ 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;
@@ -822,6 +899,18 @@ static int pci_epf_test_link_down(struct pci_epf *epf)
return 0;
}
+static irqreturn_t pci_epf_test_doorbell_handler(int irq, void *data)
+{
+ struct pci_epf_test *epf_test = data;
+ 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 IRQ_HANDLED;
+}
+
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,
@@ -921,12 +1010,46 @@ 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;
+ enum pci_barno bar;
+
+ bar = pci_epc_get_next_free_bar(epc_features, test_reg_bar + 1);
+
+ ret = request_irq(epf->db_msg[0].virq, pci_epf_test_doorbell_handler, 0,
+ "pci-test-doorbell", epf_test);
+ if (ret) {
+ dev_err(&epf->dev,
+ "Failed to request irq %d, doorbell feature is not supported\n",
+ epf->db_msg[0].virq);
+ return 0;
+ }
+
+ align = align ? align : 128;
+
+ if (epf_test->epc_features->bar[bar].type == BAR_FIXED)
+ align = max(epf_test->epc_features->bar[bar].fixed_size, align);
+
+ doorbell_addr = msg->address_hi;
+ doorbell_addr <<= 32;
+ doorbell_addr |= msg->address_lo;
+
+ reg->doorbell_offset = doorbell_addr & (align - 1);
+ reg->doorbell_data = msg->data;
+ reg->doorbell_bar = bar;
+ }
+
return 0;
}
static void pci_epf_test_unbind(struct pci_epf *epf)
{
struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+ struct pci_epf_test_reg *reg = epf_test->reg[epf_test->test_reg_bar];
struct pci_epc *epc = epf->epc;
cancel_delayed_work_sync(&epf_test->cmd_handler);
@@ -934,6 +1057,12 @@ static void pci_epf_test_unbind(struct pci_epf *epf)
pci_epf_test_clean_dma_chan(epf_test);
pci_epf_test_clear_bar(epf);
}
+
+ if (reg->doorbell_bar > 0) {
+ free_irq(epf->db_msg[0].virq, epf_test);
+ pci_epf_free_doorbell(epf);
+ }
+
pci_epf_test_free_space(epf);
}
--
2.34.1
