On Sat, Nov 16, 2024 at 09:40:44AM -0500, Frank Li wrote:
> Add three registers: doorbell_bar, doorbell_addr, and doorbell_data,
> along with doorbell_done. Use pci_epf_alloc_doorbell() to allocate a
I don't see 'doorbell_done' defined anywhere.
> 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.
>
Same here.
> To avoid broken compatibility, add new command COMMAND_ENABLE_DOORBELL
'avoid breaking compatibility between host and endpoint,...'
> 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
So the last case of old EP and host drivers will fail?
>
> 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 v7 to v8
> - rename to pci_epf_align_inbound_addr_lo_hi()
>
> Change from v6 to v7
> - use help function pci_epf_align_addr_lo_hi()
>
> 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 | 117 ++++++++++++++++++++++++++
> 1 file changed, 117 insertions(+)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index ef6677f34116e..410b2f4bb7ce7 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;
db_bar = {};
> + struct msi_msg *msg;
> + size_t offset;
> + int ret;
> +
> + if (bar < BAR_0 || bar == epf_test->test_reg_bar || !epf->db_msg) {
What is the need of BAR check here and below? pci_epf_alloc_doorbell() should've
allocated proper BAR already.
> + reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
> + return;
> + }
> +
> + msg = &epf->db_msg[0].msg;
> + ret = pci_epf_align_inbound_addr_lo_hi(epf, bar, msg->address_lo, msg->address_hi,
> + &db_bar.phys_addr, &offset);
> +
> + if (ret) {
> + reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
> + return;
> + }
> +
> + reg->doorbell_offset = offset;
> +
> + db_bar.barno = bar;
> + db_bar.size = epf->bar[bar].size;
> + db_bar.flags = epf->bar[bar].flags;
> + db_bar.addr = NULL;
Not needed if you initialize above.
> +
> + ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, &db_bar);
> + if (!ret)
> + reg->status |= STATUS_DOORBELL_ENABLE_SUCCESS;
> + else
> + reg->status |= STATUS_DOORBELL_ENABLE_FAIL;
> +}
> +
[...]
> 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 +1010,34 @@ 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;
> + enum pci_barno bar;
> +
> + bar = pci_epc_get_next_free_bar(epc_features, test_reg_bar + 1);
NO_BAR check?
- Mani
--
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