nvme: move nvme_{enable,disable,shutdown}_ctrl to common code

[linux-2.6-block.git] / drivers / nvme / host / core.c

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 63ec86a93b83a6b3682e54a8ff934716808dc516..e3179b33ff8116eb641116180cd577d53d6983d5 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -14,6 +14,7 @@
 
 #include <linux/blkdev.h>
 #include <linux/blk-mq.h>
+#include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/hdreg.h>
 #include <linux/kernel.h>
@@ -670,6 +671,111 @@ const struct block_device_operations nvme_fops = {
        .pr_ops         = &nvme_pr_ops,
 };
 
+static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
+{
+       unsigned long timeout =
+               ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
+       u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
+       int ret;
+
+       while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
+               if ((csts & NVME_CSTS_RDY) == bit)
+                       break;
+
+               msleep(100);
+               if (fatal_signal_pending(current))
+                       return -EINTR;
+               if (time_after(jiffies, timeout)) {
+                       dev_err(ctrl->dev,
+                               "Device not ready; aborting %s\n", enabled ?
+                                               "initialisation" : "reset");
+                       return -ENODEV;
+               }
+       }
+
+       return ret;
+}
+
+/*
+ * If the device has been passed off to us in an enabled state, just clear
+ * the enabled bit.  The spec says we should set the 'shutdown notification
+ * bits', but doing so may cause the device to complete commands to the
+ * admin queue ... and we don't know what memory that might be pointing at!
+ */
+int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
+{
+       int ret;
+
+       ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
+       ctrl->ctrl_config &= ~NVME_CC_ENABLE;
+
+       ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+       if (ret)
+               return ret;
+       return nvme_wait_ready(ctrl, cap, false);
+}
+
+int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
+{
+       /*
+        * Default to a 4K page size, with the intention to update this
+        * path in the future to accomodate architectures with differing
+        * kernel and IO page sizes.
+        */
+       unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
+       int ret;
+
+       if (page_shift < dev_page_min) {
+               dev_err(ctrl->dev,
+                       "Minimum device page size %u too large for host (%u)\n",
+                       1 << dev_page_min, 1 << page_shift);
+               return -ENODEV;
+       }
+
+       ctrl->page_size = 1 << page_shift;
+
+       ctrl->ctrl_config = NVME_CC_CSS_NVM;
+       ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
+       ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
+       ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
+       ctrl->ctrl_config |= NVME_CC_ENABLE;
+
+       ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+       if (ret)
+               return ret;
+       return nvme_wait_ready(ctrl, cap, true);
+}
+
+int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
+{
+       unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies;
+       u32 csts;
+       int ret;
+
+       ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
+       ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
+
+       ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
+       if (ret)
+               return ret;
+
+       while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
+               if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
+                       break;
+
+               msleep(100);
+               if (fatal_signal_pending(current))
+                       return -EINTR;
+               if (time_after(jiffies, timeout)) {
+                       dev_err(ctrl->dev,
+                               "Device shutdown incomplete; abort shutdown\n");
+                       return -ENODEV;
+               }
+       }
+
+       return ret;
+}
+
 static void nvme_free_ctrl(struct kref *kref)
 {
        struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);