Hi Frank,
On 9/12/2023 3:39 AM, Frank Li wrote:
> Add three register: doorbell_bar, doorbell_addr, doorbell_data,
> doorbell_done. Call pci_epf_alloc_doorbell() all a doorbell address space.
>
> Root complex(RC) side driver can trigger pci-epc-test's doorbell callback
> handler by write doorbell_data to mapped doorbell_bar's address space.
>
> pci-epc-test will set doorbell_done in doorbell callback.
>
> Signed-off-by: Frank Li <[email protected]>
> ---
> drivers/pci/endpoint/functions/pci-epf-test.c | 59 ++++++++++++++++++-
> 1 file changed, 58 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 1f0d2b84296a3..566549919b87b 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -11,6 +11,7 @@
> #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>
> @@ -39,17 +40,21 @@
> #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 FLAG_USE_DMA BIT(0)
>
> #define TIMER_RESOLUTION 1
>
> +#define MAGIC_VERSION_MASK GENMASK(7, 0)
> +
> static struct workqueue_struct *kpcitest_workqueue;
>
> struct pci_epf_test {
> void *reg[PCI_STD_NUM_BARS];
> struct pci_epf *epf;
> enum pci_barno test_reg_bar;
> + enum pci_barno doorbell_bar;
> size_t msix_table_offset;
> struct delayed_work cmd_handler;
> struct dma_chan *dma_chan_tx;
> @@ -74,6 +79,9 @@ struct pci_epf_test_reg {
> u32 irq_type;
> u32 irq_number;
> u32 flags;
> + u32 doorbell_bar;
You could extend test_reg_bar for doorbell to avoid using additional BAR.
> + u32 doorbell_addr;
> + u32 doorbell_data;
> } __packed;
>
Thanks,
Kishon