Luca Tettamanti wrote:
> 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 at redhat.com> 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.
>
<snip>
> 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...):
>
Looks good to me, Len would something like this be acceptable?
Regards,
Hans
> ---
> 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
