| Message ID | 20190326223938.5365-5-jeremy.linton@arm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [1/4] ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens | expand |
On Thu, Apr 04, 2019 at 12:24:38PM -0500, Jeremy Linton wrote: > On 4/4/19 12:04 PM, Will Deacon wrote: > > On Tue, Mar 26, 2019 at 05:39:38PM -0500, Jeremy Linton wrote: > > > Lets add the MODULE_TABLE and platform id_table entries so that > > > the SPE driver can attach to the ACPI platform device created by > > > the core pmu code. > > > > > > Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> > > > Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> > > > --- > > > drivers/perf/arm_spe_pmu.c | 11 +++++++++-- > > > 1 file changed, 9 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c > > > index 7cb766dafe85..ffa2c76c08bb 100644 > > > --- a/drivers/perf/arm_spe_pmu.c > > > +++ b/drivers/perf/arm_spe_pmu.c > > > @@ -1176,7 +1176,13 @@ static const struct of_device_id arm_spe_pmu_of_match[] = { > > > }; > > > MODULE_DEVICE_TABLE(of, arm_spe_pmu_of_match); > > > -static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev) > > > +static const struct platform_device_id arm_spe_match[] = { > > > + { "arm,spe-v1", 0}, > > > > It would be nice if we could avoid duplicating this string from the ACPI > > parsing code. > > Ok sure, I just need to find a good common place for it. > > > > > > + { } > > > +}; > > > +MODULE_DEVICE_TABLE(platform, arm_spe_match); > > > + > > > +static int arm_spe_pmu_device_probe(struct platform_device *pdev) > > > { > > > int ret; > > > struct arm_spe_pmu *spe_pmu; > > > @@ -1236,11 +1242,12 @@ static int arm_spe_pmu_device_remove(struct platform_device *pdev) > > > } > > > static struct platform_driver arm_spe_pmu_driver = { > > > + .id_table = arm_spe_match, > > > .driver = { > > > .name = DRVNAME, > > > .of_match_table = of_match_ptr(arm_spe_pmu_of_match), > > > > Hmm, so some other drivers don't hook .id_table like you do, but instead > > hook .acpi_match_table in the driver structure. Is that not better? > > This isn't actually an ACPI device, (aka not defined in the namespace), so > its missing much of the ACPI functionality. I think that also means its > needs to be declared this way. Looking at platform_match(), I'd really like to avoid having both an .id_table and an .of_match_table field. acpi_of_match_device() will actually use the .of_match_table, but it relies on ACPI_COMPANION returning a valid acpi_device. If we don't have one of those, perhaps we can use the .id_table exclusively and drop the .of_match_table instead? Will
Hi, On 4/16/19 8:50 AM, Will Deacon wrote: > On Thu, Apr 04, 2019 at 12:24:38PM -0500, Jeremy Linton wrote: >> On 4/4/19 12:04 PM, Will Deacon wrote: >>> On Tue, Mar 26, 2019 at 05:39:38PM -0500, Jeremy Linton wrote: >>>> Lets add the MODULE_TABLE and platform id_table entries so that >>>> the SPE driver can attach to the ACPI platform device created by >>>> the core pmu code. >>>> >>>> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> >>>> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> >>>> --- >>>> drivers/perf/arm_spe_pmu.c | 11 +++++++++-- >>>> 1 file changed, 9 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c >>>> index 7cb766dafe85..ffa2c76c08bb 100644 >>>> --- a/drivers/perf/arm_spe_pmu.c >>>> +++ b/drivers/perf/arm_spe_pmu.c >>>> @@ -1176,7 +1176,13 @@ static const struct of_device_id arm_spe_pmu_of_match[] = { >>>> }; >>>> MODULE_DEVICE_TABLE(of, arm_spe_pmu_of_match); >>>> -static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev) >>>> +static const struct platform_device_id arm_spe_match[] = { >>>> + { "arm,spe-v1", 0}, >>> >>> It would be nice if we could avoid duplicating this string from the ACPI >>> parsing code. >> >> Ok sure, I just need to find a good common place for it. There doesn't appear to be a good common place for this, so maybe arm_pmu.h, which can then be included in the spe driver is the right thing. >> >>> >>>> + { } >>>> +}; >>>> +MODULE_DEVICE_TABLE(platform, arm_spe_match); >>>> + >>>> +static int arm_spe_pmu_device_probe(struct platform_device *pdev) >>>> { >>>> int ret; >>>> struct arm_spe_pmu *spe_pmu; >>>> @@ -1236,11 +1242,12 @@ static int arm_spe_pmu_device_remove(struct platform_device *pdev) >>>> } >>>> static struct platform_driver arm_spe_pmu_driver = { >>>> + .id_table = arm_spe_match, >>>> .driver = { >>>> .name = DRVNAME, >>>> .of_match_table = of_match_ptr(arm_spe_pmu_of_match), >>> >>> Hmm, so some other drivers don't hook .id_table like you do, but instead >>> hook .acpi_match_table in the driver structure. Is that not better? >> >> This isn't actually an ACPI device, (aka not defined in the namespace), so >> its missing much of the ACPI functionality. I think that also means its >> needs to be declared this way. > > Looking at platform_match(), I'd really like to avoid having both an > .id_table and an .of_match_table field. > > acpi_of_match_device() will actually use the .of_match_table, but it relies > on ACPI_COMPANION returning a valid acpi_device. If we don't have one of Right, via the fwnode it can cause an acpi DSDT defined device with a _DSD "compatible" property to match an entry in the of_match_table compatible string. I don't think this is us... > those, perhaps we can use the .id_table exclusively and drop the > .of_match_table instead? This definitely made me do my homework, the following is AFAIK: Its possible to match on just a .id_table, but this requires matching the OF device name against the id_table name rather than against the OF compatible string (*). This doesn't seem like a good idea, despite platform_device_id entries being significantly smaller than the of_device_id ones. Plus, I think we end up with two duplicate tables because we still need the MODULE_TABLE(of,xxx) to assure that userspace can associate the modalias with the module. OTOH, it seems possible to match on module name directly ('arm_spe_pmu'), but this limits us to only a single device type for all ACPI device variations unless we put platform checks in the module itself (ick!). I suspect in the future if a spe.v2 were to come out this would be a problem unless a separate module were created. Then there is the fact this still needs a platform_device_id table, as the modalias will read "platform:arm_spe_pmu". Which will cause people to question why its not just assigned and matched against the .id_table. *(interestingly trivia: There doesn't appear to be a single arm64 module which matches on a MODULE_TABLE OF name. They only match type or compatible. Out of the 3534 modules on my machine only three do any OF table type matching, ipmi_si and two drivers for freescale networking fsl_pq_mdio and gianfar_driver. In those cases, i'm not even sure its actually necessary.)
diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c index 7cb766dafe85..ffa2c76c08bb 100644 --- a/drivers/perf/arm_spe_pmu.c +++ b/drivers/perf/arm_spe_pmu.c @@ -1176,7 +1176,13 @@ static const struct of_device_id arm_spe_pmu_of_match[] = { }; MODULE_DEVICE_TABLE(of, arm_spe_pmu_of_match); -static int arm_spe_pmu_device_dt_probe(struct platform_device *pdev) +static const struct platform_device_id arm_spe_match[] = { + { "arm,spe-v1", 0}, + { } +}; +MODULE_DEVICE_TABLE(platform, arm_spe_match); + +static int arm_spe_pmu_device_probe(struct platform_device *pdev) { int ret; struct arm_spe_pmu *spe_pmu; @@ -1236,11 +1242,12 @@ static int arm_spe_pmu_device_remove(struct platform_device *pdev) } static struct platform_driver arm_spe_pmu_driver = { + .id_table = arm_spe_match, .driver = { .name = DRVNAME, .of_match_table = of_match_ptr(arm_spe_pmu_of_match), }, - .probe = arm_spe_pmu_device_dt_probe, + .probe = arm_spe_pmu_device_probe, .remove = arm_spe_pmu_device_remove, };