o Don't announce that the timer is good when in fact it isn't timing

   at all (ie reads yield constant values). Display the width as the
   difference between max and min so that constant timers have width
   zero.
o  Get the address of the timer from the XPmTmrBlk field instead of
   the V1_PmTmrBlk field. The former is a generic address and can
   specify a memory mapped I/O address. Remove <machine/bus_pio.h>
   to account for this. The timer is now properly configured on
   machines with ACPI v2 tables, whether PIO or MEMIO. Note that
   the acpica code converts v1 tables into v2 tables so the address
   is always present in XPmTmrBlk.
o  Replace the TIMER_READ macro with a call to the read_counter()
   function and add a barrier to make sure that we observe proper
   ordering of the reads.

1 files changed, 43 insertions, 22 deletions

diff --git a/sys/dev/acpica/acpi_timer.c b/sys/dev/acpica/acpi_timer.c
index a5a0dd6..67e308a 100644
--- a/sys/dev/acpica/acpi_timer.c
+++ b/sys/dev/acpica/acpi_timer.c
@@ -37,7 +37,6 @@
 #include <sys/time.h>
 #endif
 
-#include <machine/bus_pio.h>
 #include <machine/bus.h>
 #include <machine/resource.h>
 #include <sys/rman.h>
@@ -61,9 +60,6 @@ ACPI_MODULE_NAME("TIMER")
 
 static device_t	acpi_timer_dev;
 struct resource	*acpi_timer_reg;
-#define TIMER_READ	bus_space_read_4(rman_get_bustag(acpi_timer_reg),	\
-					 rman_get_bushandle(acpi_timer_reg),	\
-					 0)
 
 static u_int	acpi_timer_frequency = 14318182/4;
 
@@ -75,6 +71,9 @@ static unsigned	acpi_timer_get_timecount_safe(struct timecounter *tc);
 static int	acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS);
 static void	acpi_timer_test(void);
 
+static u_int32_t read_counter(void);
+static int test_counter(void);
+
 /*
  * Driver hung off ACPI.
  */
@@ -106,7 +105,20 @@ static struct timecounter acpi_timer_timecounter = {
     "ACPI"
 };
 
-static int test_counter(void);
+
+static u_int32_t
+read_counter()
+{
+	bus_space_handle_t bsh;
+	bus_space_tag_t bst;
+	u_int32_t tv;
+
+	bsh = rman_get_bushandle(acpi_timer_reg);
+	bst = rman_get_bustag(acpi_timer_reg);
+	tv = bus_space_read_4(bst, bsh, 0);
+	bus_space_barrier(bst, bsh, 0, 4, BUS_SPACE_BARRIER_READ);
+	return (tv);
+}
 
 #define N 2000
 static int
@@ -117,9 +129,9 @@ test_counter()
 
 	min = 10000000;
 	max = 0;
-	last = TIMER_READ;
+	last = read_counter();
 	for (n = 0; n < N; n++) {
-		this = TIMER_READ;
+		this = read_counter();
 		delta = (this - last) & 0xffffff;
 		if (delta > max)
 			max = delta;
@@ -129,14 +141,14 @@ test_counter()
 	}
 	if (max - min > 2)
 		n = 0;
-	else if (min < 0)
+	else if (min < 0 || max == 0)
 		n = 0;
 	else
 		n = 1;
 	if (bootverbose)
 		printf("ACPI timer looks %s min = %d, max = %d, width = %d\n",
 			n ? "GOOD" : "BAD ",
-			min, max, max - min + 1);
+			min, max, max - min);
 	return (n);
 }
 
@@ -149,7 +161,8 @@ acpi_timer_identify(driver_t *driver, device_t parent)
 {
     device_t	dev;
     char	desc[40];
-    int		rid, i, j;
+    u_long	rlen, rstart;
+    int		i, j, rid, rtype;
 
     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
 
@@ -164,10 +177,17 @@ acpi_timer_identify(driver_t *driver, device_t parent)
 	return_VOID;
     }
     acpi_timer_dev = dev;
+
     rid = 0;
-    bus_set_resource(dev, SYS_RES_IOPORT, rid, AcpiGbl_FADT->V1_PmTmrBlk, sizeof(u_int32_t));
-    if ((acpi_timer_reg = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0, ~0, 1, RF_ACTIVE)) == NULL) {
-	device_printf(dev, "couldn't allocate I/O resource (port 0x%x)\n", AcpiGbl_FADT->V1_PmTmrBlk);
+    rlen = AcpiGbl_FADT->PmTmLen;
+    rtype = (AcpiGbl_FADT->XPmTmrBlk.AddressSpaceId)
+      ? SYS_RES_IOPORT : SYS_RES_MEMORY;
+    rstart = AcpiGbl_FADT->XPmTmrBlk.Address;
+    bus_set_resource(dev, rtype, rid, rstart, rlen);
+    acpi_timer_reg = bus_alloc_resource(dev, rtype, &rid, 0, ~0, 1, RF_ACTIVE);
+    if (acpi_timer_reg == NULL) {
+	device_printf(dev, "couldn't allocate I/O resource (%s 0x%lx)\n",
+	  (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart);
 	return_VOID;
     }
     if (testenv("debug.acpi.timer_test"))
@@ -186,7 +206,8 @@ acpi_timer_identify(driver_t *driver, device_t parent)
     }
     tc_init(&acpi_timer_timecounter);
 
-    sprintf(desc, "%d-bit timer at 3.579545MHz", AcpiGbl_FADT->TmrValExt ? 32 : 24);
+    sprintf(desc, "%d-bit timer at 3.579545MHz", (AcpiGbl_FADT->TmrValExt)
+      ? 32 : 24);
     device_set_desc_copy(dev, desc);
 
     return_VOID;
@@ -212,7 +233,7 @@ acpi_timer_attach(device_t dev)
 static unsigned
 acpi_timer_get_timecount(struct timecounter *tc)
 {
-    return(TIMER_READ);
+    return (read_counter());
 }
 
 /*
@@ -224,12 +245,12 @@ acpi_timer_get_timecount_safe(struct timecounter *tc)
 {
     unsigned u1, u2, u3;
 
-    u2 = TIMER_READ;
-    u3 = TIMER_READ;
+    u2 = read_counter();
+    u3 = read_counter();
     do {
 	u1 = u2;
 	u2 = u3;
-	u3 = TIMER_READ;
+	u3 = read_counter();
     } while (u1 > u2 || u2 > u3 || (u3 - u1) > 15);
     return (u2);
 }
@@ -266,9 +287,9 @@ acpi_timer_test(void)
 {
     u_int32_t	u1, u2, u3;
     
-    u1 = TIMER_READ;
-    u2 = TIMER_READ;
-    u3 = TIMER_READ;
+    u1 = read_counter();
+    u2 = read_counter();
+    u3 = read_counter();
     
     device_printf(acpi_timer_dev, "timer test in progress, reboot to quit.\n");
     for (;;) {
@@ -283,7 +304,7 @@ acpi_timer_test(void)
 	}
 	u1 = u2;
 	u2 = u3;
-	u3 = TIMER_READ;
+	u3 = read_counter();
     }
 }