| Message ID | 1392888200-27567-1-git-send-email-jiang.liu@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Thanks, Rafael. Will cc ACPI maillist next time. On 2014/2/21 4:27, Rafael J. Wysocki wrote: > On 2/20/2014 10:23 AM, Jiang Liu wrote: >> Fix regression caused by commit b072e53, which breaks loading nouveau >> driver on optimus laptops. >> >> On some platforms, ACPI _DSM method (nouveau_op_dsm_muid, function 0) >> has special requirements on the fourth parameter, which is different >> from ACPI specifications. So revert to the private implementation >> to check availability of _DSM functions instead of using common >> acpi_check_dsm() interface. >> >> Reported-and-Tested-by: Maarten Lankhorst >> <maarten.lankhorst@canonical.com> >> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> > > I'm taking this, because the commit that introduced the regression went > in through my tree. > > In the future I'll appreciate CCing ACPI-related patches to linux-acpi, > however. > > Thanks, > Rafael > > >> --- >> drivers/gpu/drm/nouveau/nouveau_acpi.c | 26 >> ++++++++++++++++++++++++-- >> 1 file changed, 24 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c >> b/drivers/gpu/drm/nouveau/nouveau_acpi.c >> index 4ef83df..83face3 100644 >> --- a/drivers/gpu/drm/nouveau/nouveau_acpi.c >> +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c >> @@ -106,6 +106,29 @@ static int nouveau_optimus_dsm(acpi_handle >> handle, int func, int arg, uint32_t * >> return 0; >> } >> +/* >> + * On some platforms, _DSM(nouveau_op_dsm_muid, func0) has special >> + * requirements on the fourth parameter, so a private implementation >> + * instead of using acpi_check_dsm(). >> + */ >> +static int nouveau_check_optimus_dsm(acpi_handle handle) >> +{ >> + int result; >> + >> + /* >> + * Function 0 returns a Buffer containing available functions. >> + * The args parameter is ignored for function 0, so just put 0 in it >> + */ >> + if (nouveau_optimus_dsm(handle, 0, 0, &result)) >> + return 0; >> + >> + /* >> + * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported. >> + * If the n-th bit is enabled, function n is supported >> + */ >> + return result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS); >> +} >> + >> static int nouveau_dsm(acpi_handle handle, int func, int arg) >> { >> int ret = 0; >> @@ -207,8 +230,7 @@ static int nouveau_dsm_pci_probe(struct pci_dev >> *pdev) >> 1 << NOUVEAU_DSM_POWER)) >> retval |= NOUVEAU_DSM_HAS_MUX; >> - if (acpi_check_dsm(dhandle, nouveau_op_dsm_muid, 0x00000100, >> - 1 << NOUVEAU_DSM_OPTIMUS_CAPS)) >> + if (nouveau_check_optimus_dsm(dhandle)) >> retval |= NOUVEAU_DSM_HAS_OPT; >> if (retval & NOUVEAU_DSM_HAS_OPT) { > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
On Fri, Feb 21, 2014 at 6:27 AM, Rafael J. Wysocki <rafael.j.wysocki@intel.com> wrote: > On 2/20/2014 10:23 AM, Jiang Liu wrote: >> >> Fix regression caused by commit b072e53, which breaks loading nouveau >> driver on optimus laptops. >> >> On some platforms, ACPI _DSM method (nouveau_op_dsm_muid, function 0) >> has special requirements on the fourth parameter, which is different >> from ACPI specifications. So revert to the private implementation >> to check availability of _DSM functions instead of using common >> acpi_check_dsm() interface. >> >> Reported-and-Tested-by: Maarten Lankhorst >> <maarten.lankhorst@canonical.com> >> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> > > > I'm taking this, because the commit that introduced the regression went in > through my tree. > > In the future I'll appreciate CCing ACPI-related patches to linux-acpi, > however. Thanks, Acked-by: Dave Airlie <airlied@redhat.com> Dave.
diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c index 4ef83df..83face3 100644 --- a/drivers/gpu/drm/nouveau/nouveau_acpi.c +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c @@ -106,6 +106,29 @@ static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t * return 0; } +/* + * On some platforms, _DSM(nouveau_op_dsm_muid, func0) has special + * requirements on the fourth parameter, so a private implementation + * instead of using acpi_check_dsm(). + */ +static int nouveau_check_optimus_dsm(acpi_handle handle) +{ + int result; + + /* + * Function 0 returns a Buffer containing available functions. + * The args parameter is ignored for function 0, so just put 0 in it + */ + if (nouveau_optimus_dsm(handle, 0, 0, &result)) + return 0; + + /* + * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported. + * If the n-th bit is enabled, function n is supported + */ + return result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS); +} + static int nouveau_dsm(acpi_handle handle, int func, int arg) { int ret = 0; @@ -207,8 +230,7 @@ static int nouveau_dsm_pci_probe(struct pci_dev *pdev) 1 << NOUVEAU_DSM_POWER)) retval |= NOUVEAU_DSM_HAS_MUX; - if (acpi_check_dsm(dhandle, nouveau_op_dsm_muid, 0x00000100, - 1 << NOUVEAU_DSM_OPTIMUS_CAPS)) + if (nouveau_check_optimus_dsm(dhandle)) retval |= NOUVEAU_DSM_HAS_OPT; if (retval & NOUVEAU_DSM_HAS_OPT) {
Fix regression caused by commit b072e53, which breaks loading nouveau driver on optimus laptops. On some platforms, ACPI _DSM method (nouveau_op_dsm_muid, function 0) has special requirements on the fourth parameter, which is different from ACPI specifications. So revert to the private implementation to check availability of _DSM functions instead of using common acpi_check_dsm() interface. Reported-and-Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> --- drivers/gpu/drm/nouveau/nouveau_acpi.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-)