Commit 2f7d4bee authored by Daniel Verkamp's avatar Daniel Verkamp
Browse files

nvme: do not set EN=0 during shutdown 



The NVMe specification recommends that orderly shutdown should just
write CC.SHN while the controller is still enabled rather than writing
CC.EN = 0 first.

This also allows removal of the now-unused nvme_ctrlr_disable() and
nvme_ctrlr_wait_for_ready() functions.

Change-Id: I4702ffda153f218ebb8ed92f0e36144b7ceded93
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent 87a3244f

lib/nvme/nvme_ctrlr.c

+0 −48
Original line number Diff line number Diff line
@@ -399,53 +399,6 @@ nvme_ctrlr_fail(struct spdk_nvme_ctrlr *ctrlr) 
	}

}



static int

nvme_ctrlr_wait_for_ready(struct spdk_nvme_ctrlr *ctrlr, int desired_ready_value)

{

	int ms_waited, ready_timeout_in_ms;

	union spdk_nvme_csts_register csts;

	union spdk_nvme_cap_lo_register cap_lo;



	/* Get ready timeout value from controller, in units of 500ms. */

	cap_lo.raw = nvme_mmio_read_4(ctrlr, cap_lo.raw);

	ready_timeout_in_ms = cap_lo.bits.to * 500;



	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);



	ms_waited = 0;



	while (csts.bits.rdy != desired_ready_value) {

		nvme_delay(1000);

		if (ms_waited++ > ready_timeout_in_ms) {

			nvme_printf(ctrlr, "controller ready did not become %d "

				    "within %d ms\n", desired_ready_value, ready_timeout_in_ms);

			return ENXIO;

		}

		csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);

	}



	return 0;

}



static void

nvme_ctrlr_disable(struct spdk_nvme_ctrlr *ctrlr)

{

	union spdk_nvme_cc_register cc;

	union spdk_nvme_csts_register csts;



	cc.raw = nvme_mmio_read_4(ctrlr, cc.raw);

	csts.raw = nvme_mmio_read_4(ctrlr, csts.raw);



	if (cc.bits.en == 1 && csts.bits.rdy == 0) {

		nvme_ctrlr_wait_for_ready(ctrlr, 1);

	}



	cc.bits.en = 0;

	nvme_mmio_write_4(ctrlr, cc.raw, cc.raw);



	nvme_ctrlr_wait_for_ready(ctrlr, 0);

}



static void

nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr)

{
@@ -1040,7 +993,6 @@ nvme_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr) 
{

	uint32_t	i;



	nvme_ctrlr_disable(ctrlr);

	nvme_ctrlr_shutdown(ctrlr);



	nvme_ctrlr_destruct_namespaces(ctrlr);