[src/trunk]: src/sys/dev/acpi The first bug: do not error out if the latency ...

[jruoho <jruoho%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/74845f8f33d3
branches:  trunk
changeset: 756465:74845f8f33d3
user:      jruoho <jruoho%NetBSD.org@localhost>
date:      Sun Jul 18 13:09:04 2010 +0000

description:
The first bug: do not error out if the latency values supplied in _CST are
larger than the upper limit constants. Only sanity check against these
defaults when operating with FADT. This is also noted in a fine print of the
specification (ACPI 4.0, p. 314): "[...] The worst-case latency to enter and
exit the C State (in microseconds). There are no latency restrictions."

diffstat:

 sys/dev/acpi/acpi_cpu_cstate.c |  92 ++++++++++++++---------------------------
 1 files changed, 32 insertions(+), 60 deletions(-)

diffs (160 lines):

diff -r 4d66c608831d -r 74845f8f33d3 sys/dev/acpi/acpi_cpu_cstate.c
--- a/sys/dev/acpi/acpi_cpu_cstate.c    Sun Jul 18 12:44:38 2010 +0000
+++ b/sys/dev/acpi/acpi_cpu_cstate.c    Sun Jul 18 13:09:04 2010 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: acpi_cpu_cstate.c,v 1.2 2010/07/18 09:39:45 jruoho Exp $ */
+/* $NetBSD: acpi_cpu_cstate.c,v 1.3 2010/07/18 13:09:04 jruoho Exp $ */
 
 /*-
  * Copyright (c) 2010 Jukka Ruohonen <jruohonen%iki.fi@localhost>
@@ -27,7 +27,7 @@
  * SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: acpi_cpu_cstate.c,v 1.2 2010/07/18 09:39:45 jruoho Exp $");
+__KERNEL_RCSID(0, "$NetBSD: acpi_cpu_cstate.c,v 1.3 2010/07/18 13:09:04 jruoho Exp $");
 
 #include <sys/param.h>
 #include <sys/cpu.h>
@@ -292,6 +292,9 @@
        (void)memset(sc->sc_cstate, 0,
            sizeof(*sc->sc_cstate) * ACPI_C_STATE_COUNT);
 
+       CTASSERT(ACPI_STATE_C0 == 0 && ACPI_STATE_C1 == 1);
+       CTASSERT(ACPI_STATE_C2 == 2 && ACPI_STATE_C3 == 3);
+
        for (count = 0, i = 1; i <= n; i++) {
 
                elm = &obj->Package.Elements[i];
@@ -324,7 +327,6 @@
        ACPI_STATUS rv = AE_OK;
        ACPI_OBJECT *obj;
        uint32_t type;
-       int i;
 
        (void)memset(&state, 0, sizeof(*cs));
 
@@ -350,6 +352,11 @@
 
        type = obj->Integer.Value;
 
+       if (type < ACPI_STATE_C1 || type > ACPI_STATE_C3) {
+               rv = AE_TYPE;
+               goto out;
+       }
+
        /*
         * Latency.
         */
@@ -408,6 +415,19 @@
                        goto out;
                }
 
+               /*
+                * Check only that the address is in the mapped space.
+                * Systems are allowed to change it when operating
+                * with _CST (see ACPI 4.0, pp. 94-95). For instance,
+                * the offset of P_LVL3 may change depending on whether
+                * acpiacad(4) is connected or disconnected.
+                */
+               if (reg->reg_addr > ao->ao_pblkaddr + ao->ao_pblklen) {
+                       rv = AE_BAD_ADDRESS;
+                       goto out;
+               }
+
+               state.cs_addr = reg->reg_addr;
                break;
 
        case ACPI_ADR_SPACE_FIXED_HARDWARE:
@@ -437,58 +457,7 @@
                goto out;
        }
 
-       state.cs_addr = reg->reg_addr;
-
-       CTASSERT(ACPICPU_C_C2_LATENCY_MAX == 100);
-       CTASSERT(ACPICPU_C_C3_LATENCY_MAX == 1000);
-
-       CTASSERT(ACPI_STATE_C0 == 0 && ACPI_STATE_C1 == 1);
-       CTASSERT(ACPI_STATE_C2 == 2 && ACPI_STATE_C3 == 3);
-
-       switch (type) {
-
-       case ACPI_STATE_C1:
-               i = 1;
-               break;
-
-       case ACPI_STATE_C2:
-
-               if (state.cs_latency > ACPICPU_C_C2_LATENCY_MAX) {
-                       rv = AE_BAD_VALUE;
-                       goto out;
-               }
-
-               i = 2;
-               break;
-
-       case ACPI_STATE_C3:
-
-               if (state.cs_latency > ACPICPU_C_C3_LATENCY_MAX) {
-                       rv = AE_BAD_VALUE;
-                       goto out;
-               }
-
-               i = 3;
-               break;
-
-       default:
-               rv = AE_TYPE;
-               goto out;
-       }
-
-       /*
-        * Check only that the address is in the mapped space.
-        * Systems are allowed to change it when operating
-        * with _CST (see ACPI 4.0, pp. 94-95). For instance,
-        * the offset of P_LVL3 may change depending on whether
-        * acpiacad(4) is connected or disconnected.
-        */
-       if (state.cs_addr > ao->ao_pblkaddr + ao->ao_pblklen) {
-               rv = AE_BAD_ADDRESS;
-               goto out;
-       }
-
-       if (cs[i].cs_method != 0) {
+       if (cs[type].cs_method != 0) {
                rv = AE_ALREADY_EXISTS;
                goto out;
        }
@@ -500,16 +469,16 @@
         *      haphazardly, depending on how long the system slept.
         *      For now, we disable the C3 state unconditionally.
         */
-       if (i == ACPI_STATE_C3) {
+       if (type == ACPI_STATE_C3) {
                sc->sc_flags |= ACPICPU_FLAG_C_NOC3;
                goto out;
        }
 #endif
 
-       cs[i].cs_addr = state.cs_addr;
-       cs[i].cs_power = state.cs_power;
-       cs[i].cs_latency = state.cs_latency;
-       cs[i].cs_method = state.cs_method;
+       cs[type].cs_addr = state.cs_addr;
+       cs[type].cs_power = state.cs_power;
+       cs[type].cs_latency = state.cs_latency;
+       cs[type].cs_method = state.cs_method;
 
 out:
        if (ACPI_FAILURE(rv))
@@ -627,6 +596,9 @@
        if (sc->sc_object.ao_pblklen < 6)
                cs[ACPI_STATE_C3].cs_method = 0;
 
+       CTASSERT(ACPICPU_C_C2_LATENCY_MAX == 100);
+       CTASSERT(ACPICPU_C_C3_LATENCY_MAX == 1000);
+
        if (AcpiGbl_FADT.C2Latency > ACPICPU_C_C2_LATENCY_MAX)
                cs[ACPI_STATE_C2].cs_method = 0;