ahci: rewrite timeout initialization code

- the "ahci_sig_timeout" variable now denotes the entire checking
  period, and the delay between checks has been hardcoded; what was
  previously "ahci_sig_checks" is now computed from those two;
- timeout values are no longer used for both millisecond and clock
  tick values, and better typed;
- the computation of timeouts is no longer off by half a second.

diff --git a/drivers/ahci/ahci.c b/drivers/ahci/ahci.c
index bbb47efddf2055dc85d5a7f4eb9d2e9b5d57a09f..4af5b1210e53f7d1e345674cca99e48f222ae78a 100644 (file)
--- a/drivers/ahci/ahci.c
+++ b/drivers/ahci/ahci.c
@@ -181,13 +181,27 @@ static int ahci_instance;                 /* driver instance number */
 
 static int ahci_verbose;                       /* verbosity level (0..4) */
 
-/* Timeout values. These can be overridden with environment variables. */
-static long ahci_spinup_timeout = SPINUP_TIMEOUT;
-static long ahci_sig_timeout = SIG_TIMEOUT;
-static long ahci_sig_checks = NR_SIG_CHECKS;
-static long ahci_command_timeout = COMMAND_TIMEOUT;
-static long ahci_transfer_timeout = TRANSFER_TIMEOUT;
-static long ahci_flush_timeout = FLUSH_TIMEOUT;
+/* Timeout-related values. */
+static clock_t ahci_spinup_timeout;
+static clock_t ahci_sig_timeout;
+static clock_t ahci_sig_delay;
+static unsigned int ahci_sig_checks;
+static clock_t ahci_command_timeout;
+static clock_t ahci_transfer_timeout;
+static clock_t ahci_flush_timeout;
+
+/* Timeout environment variable names and default values. */
+static struct {
+       char *name;                             /* environment variable name */
+       u32_t default_ms;                       /* default in milliseconds */
+       clock_t *ptr;                           /* clock ticks value pointer */
+} ahci_timevar[] = {
+       { "ahci_init_timeout",  SPINUP_TIMEOUT,    &ahci_spinup_timeout   },
+       { "ahci_sig_timeout",   SIG_TIMEOUT,       &ahci_sig_timeout      },
+       { "ahci_cmd_timeout",   COMMAND_TIMEOUT,   &ahci_command_timeout  },
+       { "ahci_io_timeout",    TRANSFER_TIMEOUT,  &ahci_transfer_timeout },
+       { "ahci_flush_timeout", FLUSH_TIMEOUT,     &ahci_flush_timeout    }
+};
 
 static int ahci_map[MAX_DRIVES];               /* device-to-port mapping */
 
@@ -202,6 +216,9 @@ static int ahci_exiting = FALSE;            /* exit after last close? */
                printf s;               \
 } while (0)
 
+/* Convert milliseconds to clock ticks. Round up. */
+#define millis_to_hz(ms)       (((ms) * sys_hz() + 999) / 1000)
+
 static void port_set_cmd(struct port_state *ps, int cmd, cmd_fis_t *fis,
        u8_t packet[ATAPI_PACKET_SIZE], prd_t *prdt, int nr_prds, int write);
 static void port_issue(struct port_state *ps, int cmd, clock_t timeout);
@@ -1330,7 +1347,7 @@ static void port_sig_check(struct port_state *ps)
                /* Try for a while before giving up. It may take seconds. */
                if (ps->left > 0) {
                        ps->left--;
-                       set_timer(&ps->cmd_info[0].timer, ahci_sig_timeout,
+                       set_timer(&ps->cmd_info[0].timer, ahci_sig_delay,
                                port_timeout, BUILD_ARG(ps - port_state, 0));
                        return;
                }
@@ -2142,23 +2159,6 @@ static void ahci_intr(unsigned int UNUSED(mask))
                panic("unable to enable IRQ: %d", r);
 }
 
-/*===========================================================================*
- *                             ahci_get_var                                 *
- *===========================================================================*/
-static void ahci_get_var(char *name, long *v, int timeout)
-{
-       /* Retrieve an environment variable, and optionall adjust it to the
-        * scale that we are using internally.
-        */
-
-       /* The value is supposed to be initialized to a default already. */
-       (void) env_parse(name, "d", 0, v, 1, LONG_MAX);
-
-       /* If this is a timeout, convert from milliseconds to ticks. */
-       if (timeout)
-               *v = (*v + 500) * sys_hz() / 1000;
-}
-
 /*===========================================================================*
  *                             ahci_get_params                              *
  *===========================================================================*/
@@ -2168,6 +2168,7 @@ static void ahci_get_params(void)
         * device-to-port mapping, which has to be parsed later.
         */
        long v;
+       int i;
 
        /* Find out which driver instance we are. */
        v = 0;
@@ -2180,12 +2181,18 @@ static void ahci_get_params(void)
        ahci_verbose = (int) v;
 
        /* Initialize timeout-related values. */
-       ahci_get_var("ahci_init_timeout", &ahci_spinup_timeout, TRUE);
-       ahci_get_var("ahci_sig_timeout", &ahci_sig_timeout, TRUE);
-       ahci_get_var("ahci_sig_checks", &ahci_sig_checks, FALSE);
-       ahci_get_var("ahci_cmd_timeout", &ahci_command_timeout, TRUE);
-       ahci_get_var("ahci_io_timeout", &ahci_transfer_timeout, TRUE);
-       ahci_get_var("ahci_flush_timeout", &ahci_flush_timeout, TRUE);
+       for (i = 0; i < sizeof(ahci_timevar) / sizeof(ahci_timevar[0]); i++) {
+               v = ahci_timevar[i].default_ms;
+
+               (void) env_parse(ahci_timevar[i].name, "d", 0, &v, 1,
+                       LONG_MAX);
+
+               *ahci_timevar[i].ptr = millis_to_hz(v);
+       }
+
+       ahci_sig_delay = millis_to_hz(SIG_DELAY);
+       ahci_sig_checks =
+               (ahci_sig_timeout + ahci_sig_delay - 1) / ahci_sig_delay;
 }
 
 /*===========================================================================*

diff --git a/drivers/ahci/ahci.h b/drivers/ahci/ahci.h
index 48b5f5318bb2eff7dedb6a57d23c6cfadcad9887..3a58e423b22b17f25b4ef6b280731fdca20daa8c 100644 (file)
--- a/drivers/ahci/ahci.h
+++ b/drivers/ahci/ahci.h
@@ -8,8 +8,7 @@
 
 /* Time values that can be set with options. */
 #define SPINUP_TIMEOUT         5000    /* initial spin-up time (ms) */
-#define SIG_TIMEOUT            250     /* time between signature checks (ms) */
-#define NR_SIG_CHECKS          60      /* maximum number of times to check */
+#define SIG_TIMEOUT            15000   /* time to wait for signature (ms) */
 #define COMMAND_TIMEOUT                10000   /* time to wait for non-I/O cmd (ms) */
 #define TRANSFER_TIMEOUT       30000   /* time to wait for I/O cmd (ms) */
 #define FLUSH_TIMEOUT          60000   /* time to wait for flush cmd (ms) */
@@ -19,6 +18,9 @@
 #define RESET_DELAY            1000    /* maximum HBA reset time (ms) */
 #define PORTREG_DELAY          500     /* maximum port register update (ms) */
 
+/* Other hardcoded time values. */
+#define SIG_DELAY              250     /* time between signature checks (ms) */
+
 /* Generic FIS layout. */
 #define ATA_FIS_TYPE                   0       /* FIS Type */
 #define        ATA_FIS_TYPE_H2D        0x27    /* Register - Host to Device */