perf/arm-cci: Allow building as a module

Fill in the few extra bits and annotations needed to make the driver
work properly as a module, and jiggle the Kconfig to expose the
driver-level ARM_CCI_PMU option.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
index 28bb5a0..110330e 100644 (file)
--- a/drivers/perf/Kconfig
+++ b/drivers/perf/Kconfig
@@ -6,30 +6,32 @@ menu "Performance monitor support"
        depends on PERF_EVENTS
 
 config ARM_CCI_PMU
-       bool
+       tristate "ARM CCI PMU driver"
+       depends on (ARM && CPU_V7) || ARM64
        select ARM_CCI
+       help
+         Support for PMU events monitoring on the ARM CCI (Cache Coherent
+         Interconnect) family of products.
+
+         If compiled as a module, it will be called arm-cci.
 
 config ARM_CCI400_PMU
-       bool "ARM CCI400 PMU support"
-       depends on (ARM && CPU_V7) || ARM64
+       bool "support CCI-400"
+       default y
+       depends on ARM_CCI_PMU
        select ARM_CCI400_COMMON
-       select ARM_CCI_PMU
        help
-         Support for PMU events monitoring on the ARM CCI-400 (cache coherent
-         interconnect). CCI-400 supports counting events related to the
-         connected slave/master interfaces.
+         CCI-400 provides 4 independent event counters counting events related
+         to the connected slave/master interfaces, plus a cycle counter.
 
 config ARM_CCI5xx_PMU
-       bool "ARM CCI-500/CCI-550 PMU support"
-       depends on (ARM && CPU_V7) || ARM64
-       select ARM_CCI_PMU
+       bool "support CCI-500/CCI-550"
+       default y
+       depends on ARM_CCI_PMU
        help
-         Support for PMU events monitoring on the ARM CCI-500/CCI-550 cache
-         coherent interconnects. Both of them provide 8 independent event counters,
-         which can count events pertaining to the slave/master interfaces as well
-         as the internal events to the CCI.
-
-         If unsure, say Y
+         CCI-500/CCI-550 both provide 8 independent event counters, which can
+         count events pertaining to the slave/master interfaces as well as the
+         internal events to the CCI.
 
 config ARM_CCN
        tristate "ARM CCN driver support"

diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c
index 33b47c2..e6fadc8 100644 (file)
--- a/drivers/perf/arm-cci.c
+++ b/drivers/perf/arm-cci.c
@@ -1407,6 +1407,7 @@ static int cci_pmu_init(struct cci_pmu *cci_pmu, struct platform_device *pdev)
        pmu_format_attr_group.attrs = model->format_attrs;
 
        cci_pmu->pmu = (struct pmu) {
+               .module         = THIS_MODULE,
                .name           = cci_pmu->model->name,
                .task_ctx_nr    = perf_invalid_context,
                .pmu_enable     = cci_pmu_enable,
@@ -1572,6 +1573,7 @@ static const struct of_device_id arm_cci_pmu_matches[] = {
 #endif
        {},
 };
+MODULE_DEVICE_TABLE(of, arm_cci_pmu_matches);
 
 static bool is_duplicate_irq(int irq, int *irqs, int nr_irqs)
 {
@@ -1693,14 +1695,27 @@ static int cci_pmu_probe(struct platform_device *pdev)
        return 0;
 }
 
+static int cci_pmu_remove(struct platform_device *pdev)
+{
+       if (!g_cci_pmu)
+               return 0;
+
+       cpuhp_remove_state(CPUHP_AP_PERF_ARM_CCI_ONLINE);
+       perf_pmu_unregister(&g_cci_pmu->pmu);
+       g_cci_pmu = NULL;
+
+       return 0;
+}
+
 static struct platform_driver cci_pmu_driver = {
        .driver = {
                   .name = DRIVER_NAME,
                   .of_match_table = arm_cci_pmu_matches,
                  },
        .probe = cci_pmu_probe,
+       .remove = cci_pmu_remove,
 };
 
-builtin_platform_driver(cci_pmu_driver);
+module_platform_driver(cci_pmu_driver);
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("ARM CCI PMU support");