[PATCH v4 05/16] misc: bcm-vk: add triggers when host panic or reboots to notify card

Scott Branden
2020-09-29T00:12:54Z

Pass down an interrupt to card in case of panic or reboot so
that card can take appropriate action to perform a clean reset.
Uses kernel notifier block either directly (register on panic list),
or implicitly (add shutdown method for PCI device).

Co-developed-by: Desmond Yan <desmond.yan@broadcom.com>
Signed-off-by: Desmond Yan <desmond.yan@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
---
drivers/misc/bcm-vk/bcm_vk.h | 2 ++
drivers/misc/bcm-vk/bcm_vk_dev.c | 29 ++++++++++++++++++++++++++++-
2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/bcm-vk/bcm_vk.h b/drivers/misc/bcm-vk/bcm_vk.h
index 0a366db693c8..f428ad9a0c3d 100644
--- a/drivers/misc/bcm-vk/bcm_vk.h
+++ b/drivers/misc/bcm-vk/bcm_vk.h
@@ -223,6 +223,8 @@ struct bcm_vk {
unsigned long wq_offload[1]; /* various flags on wq requested */
void *tdma_vaddr; /* test dma segment virtual addr */
dma_addr_t tdma_addr; /* test dma segment bus addr */
+
+ struct notifier_block panic_nb;
};

/* wq offload work items bits definitions */
diff --git a/drivers/misc/bcm-vk/bcm_vk_dev.c b/drivers/misc/bcm-vk/bcm_vk_dev.c
index cb2e315881d6..0782e2cff36d 100644
--- a/drivers/misc/bcm-vk/bcm_vk_dev.c
+++ b/drivers/misc/bcm-vk/bcm_vk_dev.c
@@ -630,6 +630,16 @@ static int bcm_vk_trigger_reset(struct bcm_vk *vk)
return 0;
}

+static int bcm_vk_on_panic(struct notifier_block *nb,
+ unsigned long e, void *p)
+{
+ struct bcm_vk *vk = container_of(nb, struct bcm_vk, panic_nb);
+
+ bcm_to_v_reset_doorbell(vk, VK_BAR0_RESET_DB_HARD);
+
+ return 0;
+}
+
static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
int err;
@@ -742,6 +752,15 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
/* sync other info */
bcm_vk_sync_card_info(vk);

+ /* register for panic notifier */
+ vk->panic_nb.notifier_call = bcm_vk_on_panic;
+ err = atomic_notifier_chain_register(&panic_notifier_list,
+ &vk->panic_nb);
+ if (err) {
+ dev_err(dev, "Fail to register panic notifier\n");
+ goto err_destroy_workqueue;
+ }
+
/*
* lets trigger an auto download. We don't want to do it serially here
* because at probing time, it is not supposed to block for a long time.
@@ -750,7 +769,7 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
if (auto_load) {
if ((boot_status & BOOT_STATE_MASK) == BROM_RUNNING) {
if (bcm_vk_trigger_autoload(vk))
- goto err_destroy_workqueue;
+ goto err_unregister_panic_notifier;
} else {
dev_err(dev,
"Auto-load skipped - BROM not in proper state (0x%x)\n",
@@ -762,6 +781,10 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)

return 0;

+err_unregister_panic_notifier:
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &vk->panic_nb);
+
err_destroy_workqueue:
destroy_workqueue(vk->wq_thread);

@@ -809,6 +832,10 @@ static void bcm_vk_remove(struct pci_dev *pdev)
bcm_vk_trigger_reset(vk);
usleep_range(BCM_VK_UCODE_BOOT_US, BCM_VK_UCODE_BOOT_MAX_US);

+ /* unregister panic notifier */
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &vk->panic_nb);
+
if (vk->tdma_vaddr)
dma_free_coherent(&pdev->dev, nr_scratch_pages * PAGE_SIZE,
vk->tdma_vaddr, vk->tdma_addr);
--
2.17.1