Il Sun, Jan 11, 2009 at 08:04:56PM +0100, Hans de Goede ha scritto:
> Luca Tettamanti wrote:
>> On Thu, Jan 8, 2009 at 5:15 PM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>> [...]
>>> So back to the discussion about changing the default of
>>> acpi_enforce_resources to strict, Jean and I have been discussing this on
>>> IRC and we feel it will most likely cause too much pain. So we would like to
>>> suggest to make the default depend up on the motherboard. Our plan is to
>>> have the default be "auto" and that will mean "lax", unless the motherboard
>>> is atk0110 (Asus ACPI interface for reading hwmon data) capable and in that
>>> case "auto" will mean "strict"
>>
>> Hum, that would mean putting ATK specific code into ACPI subsystem.
>> It's not pretty :S
>>
>
> Agreed, an alternative Jean and I discussed was to make the default
> strict for all Asus boards, that would be easier (simple strcmp on
> baseboard manufacturer). I don't know how large the atk detection code
> is.
Pretty small, 25 LoC.
>>> The plan is then to merge this acpi subsystem change and the atk0110 driver
>>> at the same time, so that people will get different hwmon capabilities, but
>>> won't loose hwmon capabilities all together. Important note: this is meant
>>> as an temporary state of affairs, the end goal is to make the checking
>>> strict.
>>>
>>> Luca do you think you could do a patch implementing the described "auto"
>>> value for acpi_enforce_resources ?
>>
>> So the logic would be:
>> - if ATK node is present and the driver is enabled -> strict
>> - otherwise -> auto
>>
>
> No the logic would be:
> if (acpi_enforce_resources == auto) {
> if (atk0110)
> acpi_enforce_resources = strict;
> else
> acpi_enforce_resources = lax;
> }
Detection is pretty easy, the only problem is that I had to hijack the
fs_initcal level, because the code shall run _after_ the interpreter has
been initialized (subsys) but before native drivers have a chance to
poke the HW. So this what I've come up with (I just wrote it - I plan to
reboot tomorrow to test it...):
---
Documentation/kernel-parameters.txt | 19 +++++++++++++
drivers/acpi/osl.c | 49 ++++++++++++++++++++++++++++++++++--
2 files changed, 66 insertions(+), 2 deletions(-)
Index: linux-2.6.git/Documentation/kernel-parameters.txt
===================================================================
--- linux-2.6.git.orig/Documentation/kernel-parameters.txt 2009-01-12 21:21:34.573074955 +0100
+++ linux-2.6.git/Documentation/kernel-parameters.txt 2009-01-12 21:22:01.164076567 +0100
@@ -251,6 +251,25 @@
to assume that this machine's pmtimer latches its value
and always returns good values.
+ acpi_enforce_resources= [ACPI]
+ { strict, auto, lax, no }
+ Check for resource conflicts between native drivers
+ and ACPI OperationRegions (SystemIO and System Memory
+ only). IO ports and memory declared in ACPI might be
+ used by the ACPI subsystem in arbitrary AML code and
+ can interfere with legacy drivers.
+ strict: access to resources claimed by ACPI is denied;
+ legacy drivers trying to access reserved resources
+ will fail to load.
+ auto (default): try and detect ACPI devices with known
+ ACPI drivers; escalates the setting to "strict" if such
+ a device is found, otherwise behaves like "lax".
+ lax: access to resources claimed by ACPI is allowed;
+ legacy drivers trying to access reserved resources
+ will load and a warning message is logged.
+ no: ACPI OperationRegions are not marked as reserved,
+ no further checks are performed.
+
agp= [AGP]
{ off | try_unsupported }
off: disable AGP support
Index: linux-2.6.git/drivers/acpi/osl.c
===================================================================
--- linux-2.6.git.orig/drivers/acpi/osl.c 2009-01-12 21:21:34.549076302 +0100
+++ linux-2.6.git/drivers/acpi/osl.c 2009-01-12 21:22:01.164076567 +0100
@@ -1063,6 +1063,9 @@
* in arbitrary AML code and can interfere with legacy drivers.
* acpi_enforce_resources= can be set to:
*
+ * - auto (3)
+ * -> detect possible conflicts with ACPI drivers and switch to
+ * strict if needed, otherwise act like lax
* - strict (2)
* -> further driver trying to access the resources will not load
* - lax (default) (1)
@@ -1073,11 +1076,12 @@
* -> ACPI Operation Region resources will not be registered
*
*/
-#define ENFORCE_RESOURCES_STRICT 2
+#define ENFORCE_RESOURCES_STRICT 3
+#define ENFORCE_RESOURCES_AUTO 2
#define ENFORCE_RESOURCES_LAX 1
#define ENFORCE_RESOURCES_NO 0
-static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
+static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_AUTO;
static int __init acpi_enforce_resources_setup(char *str)
{
@@ -1086,6 +1090,8 @@
if (!strcmp("strict", str))
acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
+ else if (!strcmp("auto", str))
+ acpi_enforce_resources = ENFORCE_RESOURCES_AUTO;
else if (!strcmp("lax", str))
acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
else if (!strcmp("no", str))
@@ -1096,6 +1102,40 @@
__setup("acpi_enforce_resources=", acpi_enforce_resources_setup);
+static int __init acpi_detect_asus_atk(void)
+{
+ struct acpi_buffer output;
+ union acpi_object *hid;
+ acpi_status ret;
+
+ if (acpi_enforce_resources != ENFORCE_RESOURCES_AUTO)
+ return 0;
+
+ output.pointer = NULL;
+ output.length = ACPI_ALLOCATE_BUFFER;
+ ret = acpi_evaluate_object_typed(NULL, "\\_SB.PCI0.SBRG.ASOC._HID",
+ NULL, &output, ACPI_TYPE_STRING);
+ if (ret == AE_OK) {
+ hid = output.pointer;
+
+ if (!strcmp("ATK0110", hid->string.pointer)) {
+ printk(KERN_DEBUG "Asus ATK0110 interface detected: "
+ "enforcing resource checking.\n");
+
+ acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
+ } else {
+ acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
+ }
+
+ ACPI_FREE(output.pointer);
+ } else {
+ acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
+ }
+
+ return 0;
+}
+fs_initcall(acpi_detect_asus_atk);
+
/* Check for resource conflicts between ACPI OperationRegions and native
* drivers */
int acpi_check_resource_conflict(struct resource *res)
Luca
--
Ligabue canta: "Tutti vogliono viaggiare in primaaaa..."
Io ci ho provato e dopo un chilometro ho fuso il motore e bruciato
la frizione...
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