sfc: Allow DRV_GEN events to be used outside of selftests

Formerly, efx_test_eventq_irq() assumed it was the only user of
driver generated events. Allow it to interoperate with other users.

We can create more than 16 channels, so align event codes with
a multiple of 256 not 16.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 18 insertions, 22 deletions

diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index 2e6fd89f2a72..ee0ea01c847e 100644
--- a/drivers/net/sfc/net_driver.h
+++ b/drivers/net/sfc/net_driver.h
@@ -336,7 +336,7 @@ enum efx_rx_alloc_method {
  * @eventq: Event queue buffer
  * @eventq_read_ptr: Event queue read pointer
  * @last_eventq_read_ptr: Last event queue read pointer value.
- * @eventq_magic: Event queue magic value for driver-generated test events
+ * @magic_count: Event queue test event count
  * @irq_count: Number of IRQs since last adaptive moderation decision
  * @irq_mod_score: IRQ moderation score
  * @rx_alloc_level: Watermark based heuristic counter for pushing descriptors
@@ -367,7 +367,7 @@ struct efx_channel {
         struct efx_special_buffer eventq;
         unsigned int eventq_read_ptr;
         unsigned int last_eventq_read_ptr;
-        unsigned int eventq_magic;
+        unsigned int magic_count;
 
         unsigned int irq_count;
         unsigned int irq_mod_score;
diff --git a/drivers/net/sfc/nic.c b/drivers/net/sfc/nic.c
index ec0bb80f5ae8..ca9cf1a33803 100644
--- a/drivers/net/sfc/nic.c
+++ b/drivers/net/sfc/nic.c
@@ -79,6 +79,10 @@ MODULE_PARM_DESC(rx_xon_thresh_bytes, "RX fifo XON threshold");
 /* Depth of RX flush request fifo */
 #define EFX_RX_FLUSH_COUNT 4
 
+/* Magic value for efx_generate_test_event() */
+#define EFX_CHANNEL_MAGIC(_channel)                     \
+        (0x00010100 + (_channel)->channel)
+
 /**************************************************************************
  *
  * Solarstorm hardware access
@@ -993,8 +997,10 @@ int efx_nic_process_eventq(struct efx_channel *channel, int budget)
                         }
                         break;
                 case FSE_AZ_EV_CODE_DRV_GEN_EV:
-                        channel->eventq_magic = EFX_QWORD_FIELD(
-                                event, FSF_AZ_DRV_GEN_EV_MAGIC);
+                        if (EFX_QWORD_FIELD(event, FSF_AZ_DRV_GEN_EV_MAGIC)
+                            == EFX_CHANNEL_MAGIC(channel))
+                                ++channel->magic_count;
+
                         EFX_LOG(channel->efx, "channel %d received generated "
                                 "event "EFX_QWORD_FMT"\n", channel->channel,
                                 EFX_QWORD_VAL(event));
@@ -1088,12 +1094,9 @@ void efx_nic_remove_eventq(struct efx_channel *channel)
 }
 
 
-/* Generates a test event on the event queue.  A subsequent call to
- * process_eventq() should pick up the event and place the value of
- * "magic" into channel->eventq_magic;
- */
-void efx_nic_generate_test_event(struct efx_channel *channel, unsigned int magic)
+void efx_nic_generate_test_event(struct efx_channel *channel)
 {
+        unsigned int magic = EFX_CHANNEL_MAGIC(channel);
         efx_qword_t test_event;
 
         EFX_POPULATE_QWORD_2(test_event, FSF_AZ_EV_CODE,
diff --git a/drivers/net/sfc/nic.h b/drivers/net/sfc/nic.h
index bbc2c0c2f843..186aab564c4a 100644
--- a/drivers/net/sfc/nic.h
+++ b/drivers/net/sfc/nic.h
@@ -190,8 +190,7 @@ extern int efx_nic_rx_xoff_thresh, efx_nic_rx_xon_thresh;
 /* Interrupts and test events */
 extern int efx_nic_init_interrupt(struct efx_nic *efx);
 extern void efx_nic_enable_interrupts(struct efx_nic *efx);
-extern void efx_nic_generate_test_event(struct efx_channel *channel,
-                                        unsigned int magic);
+extern void efx_nic_generate_test_event(struct efx_channel *channel);
 extern void efx_nic_generate_interrupt(struct efx_nic *efx);
 extern void efx_nic_disable_interrupts(struct efx_nic *efx);
 extern void efx_nic_fini_interrupt(struct efx_nic *efx);
diff --git a/drivers/net/sfc/selftest.c b/drivers/net/sfc/selftest.c
index 52ac14af83a4..c088740e3493 100644
--- a/drivers/net/sfc/selftest.c
+++ b/drivers/net/sfc/selftest.c
@@ -161,23 +161,17 @@ static int efx_test_interrupts(struct efx_nic *efx,
 static int efx_test_eventq_irq(struct efx_channel *channel,
                                struct efx_self_tests *tests)
 {
-        unsigned int magic, count;
-
-        /* Channel specific code, limited to 20 bits */
-        magic = (0x00010150 + channel->channel);
-        EFX_LOG(channel->efx, "channel %d testing event queue with code %x\n",
-                channel->channel, magic);
+        unsigned int magic_count, count;
 
         tests->eventq_dma[channel->channel] = -1;
         tests->eventq_int[channel->channel] = -1;
         tests->eventq_poll[channel->channel] = -1;
 
-        /* Reset flag and zero magic word */
+        magic_count = channel->magic_count;
         channel->efx->last_irq_cpu = -1;
-        channel->eventq_magic = 0;
         smp_wmb();
 
-        efx_nic_generate_test_event(channel, magic);
+        efx_nic_generate_test_event(channel);
 
         /* Wait for arrival of interrupt */
         count = 0;
@@ -187,7 +181,7 @@ static int efx_test_eventq_irq(struct efx_channel *channel,
                 if (channel->work_pending)
                         efx_process_channel_now(channel);
 
-                if (channel->eventq_magic == magic)
+                if (channel->magic_count != magic_count)
                         goto eventq_ok;
         } while (++count < 2);
 
@@ -204,7 +198,7 @@ static int efx_test_eventq_irq(struct efx_channel *channel,
 
         /* Check to see if event was received even if interrupt wasn't */
         efx_process_channel_now(channel);
-        if (channel->eventq_magic == magic) {
+        if (channel->magic_count != magic_count) {
                 EFX_ERR(channel->efx, "channel %d event was generated, but "
                         "failed to trigger an interrupt\n", channel->channel);
                 tests->eventq_dma[channel->channel] = 1;