Changeset 31de325 in mainline

Timestamp:

2009-08-08T15:21:01Z (15 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

330965c

Parents:

54d0ddc

Message:

Implement simple timeout when waiting for device.

Location:

uspace/srv/bd/ata_bd

Files:

• ata_bd.c (modified) (10 diffs)
• ata_bd.h (modified) (1 diff)

uspace/srv/bd/ata_bd/ata_bd.c

@@ -86 +86 @@
     const void *buf);
 static int drive_identify(int drive_id, disk_t *d);
-static uint8_t wait_status(unsigned set, unsigned n_reset);
+static int wait_status(unsigned set, unsigned n_reset, uint8_t *pstatus,
+    unsigned timeout);
 
 int main(int argc, char **argv)
@@ -101 +102 @@
                 return -1;
 
-        (void) drive_identify(0, &disk[0]);
-        (void) drive_identify(1, &disk[1]);
+        for (i = 0; i < MAX_DISKS; i++) {
+                printf("Identify drive %d... ", i);
+                fflush(stdout);
+
+                rc = drive_identify(i, &disk[i]);
+
+                if (rc == EOK) {
+                        printf("%u cylinders, %u heads, %u sectors\n",
+                            disk[i].cylinders, disk[i].heads, disk[i].sectors);
+                } else {
+                        printf("Not found.\n");
+                }
+        }
 
         n_disks = 0;
@@ -295 +307 @@
         size_t i;
 
-        printf("Identify drive %d... ", disk_id);
-        fflush(stdout);
-
         drv_head = ((disk_id != 0) ? DHR_DRV : 0);
         d->present = false;
 
-        wait_status(0, ~SR_BSY);
+        if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_PROBE) != EOK)
+                return EIO;
+
         pio_write_8(&cmd->drive_head, drv_head);
 
         /*
-         * Detect if drive is present. This is only temorary.
-         * We should really try for some time before giving up.
+         * This is where we would most likely expect a non-existing device to
+         * show up by not setting SR_DRDY.
          */
-        status = wait_status(0, ~SR_BSY);
-
-        if ((status & SR_DRDY) == 0) {
-                printf("None attached.\n");
-                return ENOENT;
-        }
-        /***/
-
-        wait_status(SR_DRDY, ~SR_BSY);
+        if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_PROBE) != EOK)
+                return EIO;
+
         pio_write_8(&cmd->command, CMD_IDENTIFY_DRIVE);
 
-        status = wait_status(0, ~SR_BSY);
+        if (wait_status(0, ~SR_BSY, &status, TIMEOUT_PROBE) != EOK)
+                return EIO;
 
         /* Read data from the disk buffer. */
@@ -344 +350 @@
 
         d->blocks = d->cylinders * d->heads * d->sectors;
-
-        printf("Geometry: %u cylinders, %u heads, %u sectors\n",
-                d->cylinders, d->heads, d->sectors);
 
         d->present = true;
@@ -396 +399 @@
         /* Program a Read Sectors operation. */
 
-        wait_status(0, ~SR_BSY);
+        if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_BSY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
+
         pio_write_8(&cmd->drive_head, drv_head);
 
-        wait_status(SR_DRDY, ~SR_BSY);
+        if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_DRDY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
+
         pio_write_8(&cmd->sector_count, 1);
         pio_write_8(&cmd->sector_number, s);
@@ -407 +418 @@
         pio_write_8(&cmd->command, CMD_READ_SECTORS);
 
-        status = wait_status(0, ~SR_BSY);
-
-        /* Read data from the disk buffer. */
+        if (wait_status(0, ~SR_BSY, &status, TIMEOUT_BSY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
 
         if ((status & SR_DRQ) != 0) {
+                /* Read data from the device buffer. */
+
                 for (i = 0; i < block_size / 2; i++) {
                         data = pio_read_16(&cmd->data_port);
@@ -464 +478 @@
         fibril_mutex_lock(&d->lock);
 
-        /* Program a Read Sectors operation. */
-
-        wait_status(0, ~SR_BSY);
+        /* Program a Write Sectors operation. */
+
+        if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_BSY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
+
         pio_write_8(&cmd->drive_head, drv_head);
 
-        wait_status(SR_DRDY, ~SR_BSY);
+        if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_DRDY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
+
         pio_write_8(&cmd->sector_count, 1);
         pio_write_8(&cmd->sector_number, s);
@@ -477 +499 @@
         pio_write_8(&cmd->command, CMD_WRITE_SECTORS);
 
-        status = wait_status(0, ~SR_BSY);
-
-        /* Write data to the disk buffer. */
+        if (wait_status(0, ~SR_BSY, &status, TIMEOUT_BSY) != EOK) {
+                fibril_mutex_unlock(&d->lock);
+                return EIO;
+        }
 
         if ((status & SR_DRQ) != 0) {
+                /* Write data to the device buffer. */
+
                 for (i = 0; i < block_size / 2; i++) {
                         pio_write_16(&cmd->data_port, ((uint16_t *) buf)[i]);
@@ -495 +520 @@
 }
 
-/** Wait until some status bits are set and some reset.
+/** Wait until some status bits are set and some are reset.
  *
  * Example: wait_status(SR_DRDY, ~SR_BSY) waits for SR_DRDY to become
@@ -502 +527 @@
  * @param set           Combination if bits which must be all set.
  * @param n_reset       Negated combination of bits which must be all reset.
- * @return              The last value of status register that was read.
- */
-static uint8_t wait_status(unsigned set, unsigned n_reset)
+ * @param pstatus       Pointer where to store last read status or NULL.
+ * @param timeout       Timeout in 10ms units.
+ *
+ * @return              EOK on success, EIO on timeout.
+ */
+static int wait_status(unsigned set, unsigned n_reset, uint8_t *pstatus,
+    unsigned timeout)
 {
         uint8_t status;
-
-        do {
+        int cnt;
+
+        status = pio_read_8(&cmd->status);
+
+        /*
+         * This is crude, yet simple. First try with 1us delays
+         * (most likely the device will respond very fast). If not,
+         * start trying every 10 ms.
+         */
+
+        cnt = 100;
+        while ((status & ~n_reset) != 0 || (status & set) != set) {
+                async_usleep(1);
+                --cnt;
+                if (cnt <= 0) break;
+
                 status = pio_read_8(&cmd->status);
-        } while ((status & ~n_reset) != 0 || (status & set) != set);
-
-        return status;
+        }
+
+        cnt = timeout;
+        while ((status & ~n_reset) != 0 || (status & set) != set) {
+                async_usleep(10000);
+                --cnt;
+                if (cnt <= 0) break;
+
+                status = pio_read_8(&cmd->status);
+        }
+
+        if (pstatus)
+                *pstatus = status;
+
+        if (cnt == 0)
+                return EIO;
+
+        return EOK;
 }
 

uspace/srv/bd/ata_bd/ata_bd.h

@@ -135 +135 @@
 };
 
+/** Timeout definitions. Unit is 10 ms. */
+enum ata_timeout {
+        TIMEOUT_PROBE   =  100, /*  1 s */
+        TIMEOUT_BSY     =  100, /*  1 s */
+        TIMEOUT_DRDY    = 1000  /* 10 s */
+};
+
 typedef struct {
         bool present;