Subject: [PATCH 2/5] arm-cci: Abstract the CCI400 PMU speicific definitions

From: [email-masked] (Will Deacon)
Date: Tue, 17 Mar 2015 18:49:20 +0000

On Tue, Mar 10, 2015 at 03:18:52PM +0000, Suzuki K. Poulose wrote:
> From: "Suzuki K. Poulose" <[email-masked]>
> 
> CCI400 has different event specifications for PMU, for revsion
> 0 and revision 1. As of now, we check the revision every single
> time before using the parameters for the PMU. This patch abstracts
> the details of the pmu models in a struct (cci_pmu_model) and
> stores the information in cci_pmu at initialisation time, avoiding
> multiple probe operations.
> 
> Changes since V2:
>  - Cleanup event validation(pmu_validate_hw_event). Get rid of
>    helper functions:
> 	pmu_is_valid_slave_event
> 	pmu_is_valid_master_event
> 
> Signed-off-by: Suzuki K. Poulose <[email-masked]>
> ---

Looks good to me:

Reviewed-by: Will Deacon <[email-masked]>

Will

>  drivers/bus/arm-cci.c |  141 ++++++++++++++++++++++++++++---------------------
>  1 file changed, 81 insertions(+), 60 deletions(-)
> 
> diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c
> index ea39fc2..f88383e 100644
> --- a/drivers/bus/arm-cci.c
> +++ b/drivers/bus/arm-cci.c
> @@ -79,19 +79,38 @@ static const struct of_device_id arm_cci_matches[] = {
>  
>  #define CCI_PMU_MAX_HW_EVENTS 5   /* CCI PMU has 4 counters + 1 cycle counter */
>  
> +/* Types of interfaces that can generate events */
> +enum {
> +	CCI_IF_SLAVE,
> +	CCI_IF_MASTER,
> +	CCI_IF_MAX,
> +};
> +
> +struct event_range {
> +	u32 min;
> +	u32 max;
> +};
> +
>  struct cci_pmu_hw_events {
>  	struct perf_event *events[CCI_PMU_MAX_HW_EVENTS];
>  	unsigned long used_mask[BITS_TO_LONGS(CCI_PMU_MAX_HW_EVENTS)];
>  	raw_spinlock_t pmu_lock;
>  };
>  
> +struct cci_pmu_model {
> +	char *name;
> +	struct event_range event_ranges[CCI_IF_MAX];
> +};
> +
> +static struct cci_pmu_model cci_pmu_models[];
> +
>  struct cci_pmu {
>  	void __iomem *base;
>  	struct pmu pmu;
>  	int nr_irqs;
>  	int irqs[CCI_PMU_MAX_HW_EVENTS];
>  	unsigned long active_irqs;
> -	struct pmu_port_event_ranges *port_ranges;
> +	const struct cci_pmu_model *model;
>  	struct cci_pmu_hw_events hw_events;
>  	struct platform_device *plat_device;
>  	int num_events;
> @@ -152,53 +171,11 @@ enum cci400_perf_events {
>  #define CCI_REV_R1_MASTER_PORT_MIN_EV	0x00
>  #define CCI_REV_R1_MASTER_PORT_MAX_EV	0x11
>  
> -struct pmu_port_event_ranges {
> -	u8 slave_min;
> -	u8 slave_max;
> -	u8 master_min;
> -	u8 master_max;
> -};
> -
> -static struct pmu_port_event_ranges port_event_range[] = {
> -	[CCI_REV_R0] = {
> -		.slave_min = CCI_REV_R0_SLAVE_PORT_MIN_EV,
> -		.slave_max = CCI_REV_R0_SLAVE_PORT_MAX_EV,
> -		.master_min = CCI_REV_R0_MASTER_PORT_MIN_EV,
> -		.master_max = CCI_REV_R0_MASTER_PORT_MAX_EV,
> -	},
> -	[CCI_REV_R1] = {
> -		.slave_min = CCI_REV_R1_SLAVE_PORT_MIN_EV,
> -		.slave_max = CCI_REV_R1_SLAVE_PORT_MAX_EV,
> -		.master_min = CCI_REV_R1_MASTER_PORT_MIN_EV,
> -		.master_max = CCI_REV_R1_MASTER_PORT_MAX_EV,
> -	},
> -};
> -
> -/*
> - * Export different PMU names for the different revisions so userspace knows
> - * because the event ids are different
> - */
> -static char *const pmu_names[] = {
> -	[CCI_REV_R0] = "CCI_400",
> -	[CCI_REV_R1] = "CCI_400_r1",
> -};
> -
> -static int pmu_is_valid_slave_event(u8 ev_code)
> -{
> -	return pmu->port_ranges->slave_min <= ev_code &&
> -		ev_code <= pmu->port_ranges->slave_max;
> -}
> -
> -static int pmu_is_valid_master_event(u8 ev_code)
> -{
> -	return pmu->port_ranges->master_min <= ev_code &&
> -		ev_code <= pmu->port_ranges->master_max;
> -}
> -
>  static int pmu_validate_hw_event(u8 hw_event)
>  {
>  	u8 ev_source = CCI_PMU_EVENT_SOURCE(hw_event);
>  	u8 ev_code = CCI_PMU_EVENT_CODE(hw_event);
> +	int if_type;
>  
>  	switch (ev_source) {
>  	case CCI_PORT_S0:
> @@ -207,18 +184,22 @@ static int pmu_validate_hw_event(u8 hw_event)
>  	case CCI_PORT_S3:
>  	case CCI_PORT_S4:
>  		/* Slave Interface */
> -		if (pmu_is_valid_slave_event(ev_code))
> -			return hw_event;
> +		if_type = CCI_IF_SLAVE;
>  		break;
>  	case CCI_PORT_M0:
>  	case CCI_PORT_M1:
>  	case CCI_PORT_M2:
>  		/* Master Interface */
> -		if (pmu_is_valid_master_event(ev_code))
> -			return hw_event;
> +		if_type = CCI_IF_MASTER;
>  		break;
> +	default:
> +		return -ENOENT;
>  	}
>  
> +	if (ev_code >= pmu->model->event_ranges[if_type].min &&
> +		ev_code <= pmu->model->event_ranges[if_type].max)
> +		return hw_event;
> +
>  	return -ENOENT;
>  }
>  
> @@ -234,11 +215,9 @@ static int probe_cci_revision(void)
>  		return CCI_REV_R1;
>  }
>  
> -static struct pmu_port_event_ranges *port_range_by_rev(void)
> +static const struct cci_pmu_model *probe_cci_model(struct platform_device *pdev)
>  {
> -	int rev = probe_cci_revision();
> -
> -	return &port_event_range[rev];
> +	return &cci_pmu_models[probe_cci_revision()];
>  }
>  
>  static int pmu_is_valid_counter(struct cci_pmu *cci_pmu, int idx)
> @@ -807,9 +786,9 @@ static const struct attribute_group *pmu_attr_groups[] = {
>  
>  static int cci_pmu_init(struct cci_pmu *cci_pmu, struct platform_device *pdev)
>  {
> -	char *name = pmu_names[probe_cci_revision()];
> +	char *name = cci_pmu->model->name;
>  	cci_pmu->pmu = (struct pmu) {
> -		.name		= pmu_names[probe_cci_revision()],
> +		.name		= cci_pmu->model->name,
>  		.task_ctx_nr	= perf_invalid_context,
>  		.pmu_enable	= cci_pmu_enable,
>  		.pmu_disable	= cci_pmu_disable,
> @@ -862,6 +841,35 @@ static struct notifier_block cci_pmu_cpu_nb = {
>  	.priority	= CPU_PRI_PERF + 1,
>  };
>  
> +static struct cci_pmu_model cci_pmu_models[] = {
> +	[CCI_REV_R0] = {
> +		.name = "CCI_400",
> +		.event_ranges = {
> +			[CCI_IF_SLAVE] = {
> +				CCI_REV_R0_SLAVE_PORT_MIN_EV,
> +				CCI_REV_R0_SLAVE_PORT_MAX_EV,
> +			},
> +			[CCI_IF_MASTER] = {
> +				CCI_REV_R0_MASTER_PORT_MIN_EV,
> +				CCI_REV_R0_MASTER_PORT_MAX_EV,
> +			},
> +		},
> +	},
> +	[CCI_REV_R1] = {
> +		.name = "CCI_400_r1",
> +		.event_ranges = {
> +			[CCI_IF_SLAVE] = {
> +				CCI_REV_R1_SLAVE_PORT_MIN_EV,
> +				CCI_REV_R1_SLAVE_PORT_MAX_EV,
> +			},
> +			[CCI_IF_MASTER] = {
> +				CCI_REV_R1_MASTER_PORT_MIN_EV,
> +				CCI_REV_R1_MASTER_PORT_MAX_EV,
> +			},
> +		},
> +	},
> +};
> +
>  static const struct of_device_id arm_cci_pmu_matches[] = {
>  	{
>  		.compatible = "arm,cci-400-pmu",
> @@ -869,6 +877,16 @@ static const struct of_device_id arm_cci_pmu_matches[] = {
>  	{},
>  };
>  
> +static inline const struct cci_pmu_model *get_cci_model(struct platform_device *pdev)
> +{
> +	const struct of_device_id *match = of_match_node(arm_cci_pmu_matches,
> +							pdev->dev.of_node);
> +	if (!match)
> +		return NULL;
> +
> +	return probe_cci_model(pdev);
> +}
> +
>  static bool is_duplicate_irq(int irq, int *irqs, int nr_irqs)
>  {
>  	int i;
> @@ -884,11 +902,19 @@ static int cci_pmu_probe(struct platform_device *pdev)
>  {
>  	struct resource *res;
>  	int i, ret, irq;
> +	const struct cci_pmu_model *model;
> +
> +	model = get_cci_model(pdev);
> +	if (!model) {
> +		dev_warn(&pdev->dev, "CCI PMU version not supported\n");
> +		return -ENODEV;
> +	}
>  
>  	pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
>  	if (!pmu)
>  		return -ENOMEM;
>  
> +	pmu->model = model;
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	pmu->base = devm_ioremap_resource(&pdev->dev, res);
>  	if (IS_ERR(pmu->base))
> @@ -920,12 +946,6 @@ static int cci_pmu_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	pmu->port_ranges = port_range_by_rev();
> -	if (!pmu->port_ranges) {
> -		dev_warn(&pdev->dev, "CCI PMU version not supported\n");
> -		return -EINVAL;
> -	}
> -
>  	raw_spin_lock_init(&pmu->hw_events.pmu_lock);
>  	mutex_init(&pmu->reserve_mutex);
>  	atomic_set(&pmu->active_events, 0);
> @@ -939,6 +959,7 @@ static int cci_pmu_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
>  
> +	pr_info("ARM %s PMU driver probed", pmu->model->name);
>  	return 0;
>  }
>  
> -- 
> 1.7.9.5
>