nvme: Do a clean NVMe shutdown
The brute-force controller disable method can end up racing controller
initialization and causing a crash when we shut down Apple ANS2 NVMe
controllers. Do a proper controlled shutdown, which does block until
things are quiesced properly. This is nicer in general for all
controllers.
Signed-off-by: Hector Martin <marcan@marcan.st>
Tested-by: Mark Kettenis <kettenis@openbsd.org> (firefly-rk3399)
diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c
index a305305..5fd2fb9 100644
--- a/drivers/nvme/nvme.c
+++ b/drivers/nvme/nvme.c
@@ -27,9 +27,8 @@
#define IO_TIMEOUT 30
#define MAX_PRP_POOL 512
-static int nvme_wait_ready(struct nvme_dev *dev, bool enabled)
+static int nvme_wait_csts(struct nvme_dev *dev, u32 mask, u32 val)
{
- u32 bit = enabled ? NVME_CSTS_RDY : 0;
int timeout;
ulong start;
@@ -38,7 +37,7 @@
start = get_timer(0);
while (get_timer(start) < timeout) {
- if ((readl(&dev->bar->csts) & NVME_CSTS_RDY) == bit)
+ if ((readl(&dev->bar->csts) & mask) == val)
return 0;
}
@@ -295,7 +294,7 @@
dev->ctrl_config |= NVME_CC_ENABLE;
writel(dev->ctrl_config, &dev->bar->cc);
- return nvme_wait_ready(dev, true);
+ return nvme_wait_csts(dev, NVME_CSTS_RDY, NVME_CSTS_RDY);
}
static int nvme_disable_ctrl(struct nvme_dev *dev)
@@ -304,9 +303,18 @@
dev->ctrl_config &= ~NVME_CC_ENABLE;
writel(dev->ctrl_config, &dev->bar->cc);
- return nvme_wait_ready(dev, false);
+ return nvme_wait_csts(dev, NVME_CSTS_RDY, 0);
}
+static int nvme_shutdown_ctrl(struct nvme_dev *dev)
+{
+ dev->ctrl_config &= ~NVME_CC_SHN_MASK;
+ dev->ctrl_config |= NVME_CC_SHN_NORMAL;
+ writel(dev->ctrl_config, &dev->bar->cc);
+
+ return nvme_wait_csts(dev, NVME_CSTS_SHST_MASK, NVME_CSTS_SHST_CMPLT);
+}
+
static void nvme_free_queue(struct nvme_queue *nvmeq)
{
free((void *)nvmeq->cqes);
@@ -904,6 +912,13 @@
int nvme_shutdown(struct udevice *udev)
{
struct nvme_dev *ndev = dev_get_priv(udev);
+ int ret;
+
+ ret = nvme_shutdown_ctrl(ndev);
+ if (ret < 0) {
+ printf("Error: %s: Shutdown timed out!\n", udev->name);
+ return ret;
+ }
return nvme_disable_ctrl(ndev);
}