Re: [PATCH v2] irqchip: xilinx: Add support for multiple instances

[Michal Simek <michal.simek@xilinx.com>]

Hi Mubin,

On 05. 02. 20 15:05, Mubin Usman Sayyed wrote:
> From: Mubin Sayyed <mubin.usman.sayyed@xilinx.com>
> 
> This patch adds support for multiple instances of
> xilinx interrupt controller. Below configurations are
> supported by driver,
> 
> - peripheral->xilinx-intc->xilinx-intc->gic
> - peripheral->xilinx-intc->xilinx-intc
> 
> Signed-off-by: Anirudha Sarangi <anirudha.sarangi@xilinx.com>
> Signed-off-by: Mubin Sayyed <mubin.usman.sayyed@xilinx.com>
> ---
> Changes for v2:
>         - Removed write_fn/read_fn hooks, used xintc_write/
> 	  xintc_read directly
>         - Moved primary_intc declaration after xintc_irq_chip
> ---
>  drivers/irqchip/irq-xilinx-intc.c | 121 +++++++++++++++++++++++---------------
>  1 file changed, 73 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-xilinx-intc.c b/drivers/irqchip/irq-xilinx-intc.c
> index e3043de..14cb630 100644
> --- a/drivers/irqchip/irq-xilinx-intc.c
> +++ b/drivers/irqchip/irq-xilinx-intc.c
> @@ -38,29 +38,32 @@ struct xintc_irq_chip {
>  	void		__iomem *base;
>  	struct		irq_domain *root_domain;
>  	u32		intr_mask;
> +	struct			irq_chip *intc_dev;
> +	u32				nr_irq;

indentation is weird.

>  };
>  
> -static struct xintc_irq_chip *xintc_irqc;
> +static struct xintc_irq_chip *primary_intc;
>  
> -static void xintc_write(int reg, u32 data)
> +static void xintc_write(void __iomem *addr, u32 data)

The best would be if prototype is
static void xintc_write(struct xintc_irq_chip *irqc, int reg, u32 data)


>  {
>  	if (static_branch_unlikely(&xintc_is_be))
> -		iowrite32be(data, xintc_irqc->base + reg);
> +		iowrite32be(data, addr);
>  	else
> -		iowrite32(data, xintc_irqc->base + reg);
> +		iowrite32(data, addr);
>  }
>  
> -static unsigned int xintc_read(int reg)
> +static unsigned int xintc_read(void __iomem *addr)

And the same here.
static unsigned int xintc_read(struct xintc_irq_chip *irqc, int reg)

>  {
>  	if (static_branch_unlikely(&xintc_is_be))
> -		return ioread32be(xintc_irqc->base + reg);
> +		return ioread32be(addr);
>  	else
> -		return ioread32(xintc_irqc->base + reg);
> +		return ioread32(addr);
>  }
>  
>  static void intc_enable_or_unmask(struct irq_data *d)
>  {
>  	unsigned long mask = 1 << d->hwirq;
> +	struct xintc_irq_chip *local_intc = irq_data_get_irq_chip_data(d);

code is using variable name as irqc below. I think that will be the best
to use it in all functions. It means s/local_intc/irqc/g'


>  
>  	pr_debug("irq-xilinx: enable_or_unmask: %ld\n", d->hwirq);
>  
> @@ -69,47 +72,57 @@ static void intc_enable_or_unmask(struct irq_data *d)
>  	 * acks the irq before calling the interrupt handler
>  	 */
>  	if (irqd_is_level_type(d))
> -		xintc_write(IAR, mask);
> +		xintc_write(local_intc->base + IAR, mask);
>  
> -	xintc_write(SIE, mask);
> +	xintc_write(local_intc->base + SIE, mask);
>  }
>  
>  static void intc_disable_or_mask(struct irq_data *d)
>  {
> +	struct xintc_irq_chip *local_intc = irq_data_get_irq_chip_data(d);
> +
>  	pr_debug("irq-xilinx: disable: %ld\n", d->hwirq);
> -	xintc_write(CIE, 1 << d->hwirq);
> +	xintc_write(local_intc->base + CIE, 1 << d->hwirq);
>  }
>  
>  static void intc_ack(struct irq_data *d)
>  {
> +	struct xintc_irq_chip *local_intc = irq_data_get_irq_chip_data(d);
> +
>  	pr_debug("irq-xilinx: ack: %ld\n", d->hwirq);
> -	xintc_write(IAR, 1 << d->hwirq);
> +	xintc_write(local_intc->base + IAR, 1 << d->hwirq);
>  }
>  
>  static void intc_mask_ack(struct irq_data *d)
>  {
>  	unsigned long mask = 1 << d->hwirq;
> +	struct xintc_irq_chip *local_intc = irq_data_get_irq_chip_data(d);
>  
>  	pr_debug("irq-xilinx: disable_and_ack: %ld\n", d->hwirq);
> -	xintc_write(CIE, mask);
> -	xintc_write(IAR, mask);
> +	xintc_write(local_intc->base + CIE, mask);
> +	xintc_write(local_intc->base + IAR, mask);
>  }
>  
> -static struct irq_chip intc_dev = {
> -	.name = "Xilinx INTC",
> -	.irq_unmask = intc_enable_or_unmask,
> -	.irq_mask = intc_disable_or_mask,
> -	.irq_ack = intc_ack,
> -	.irq_mask_ack = intc_mask_ack,
> -};
> +static unsigned int xintc_get_irq_local(struct xintc_irq_chip *local_intc)
> +{
> +	int hwirq, irq = -1;
> +
> +	hwirq = xintc_read(local_intc->base + IVR);
> +	if (hwirq != -1U)
> +		irq = irq_find_mapping(local_intc->root_domain, hwirq);
> +
> +	pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
> +
> +	return irq;
> +}
>  
>  unsigned int xintc_get_irq(void)
>  {
> -	unsigned int hwirq, irq = -1;
> +	int hwirq, irq = -1;
>  
> -	hwirq = xintc_read(IVR);
> +	hwirq = xintc_read(primary_intc->base + IVR);
>  	if (hwirq != -1U)
> -		irq = irq_find_mapping(xintc_irqc->root_domain, hwirq);
> +		irq = irq_find_mapping(primary_intc->root_domain, hwirq);
>  
>  	pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
>  
> @@ -118,15 +131,18 @@ unsigned int xintc_get_irq(void)
>  
>  static int xintc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
>  {
> -	if (xintc_irqc->intr_mask & (1 << hw)) {
> -		irq_set_chip_and_handler_name(irq, &intc_dev,
> +	struct xintc_irq_chip *local_intc = d->host_data;
> +
> +	if (local_intc->intr_mask & (1 << hw)) {
> +		irq_set_chip_and_handler_name(irq, local_intc->intc_dev,
>  						handle_edge_irq, "edge");
>  		irq_clear_status_flags(irq, IRQ_LEVEL);
>  	} else {
> -		irq_set_chip_and_handler_name(irq, &intc_dev,
> +		irq_set_chip_and_handler_name(irq, local_intc->intc_dev,
>  						handle_level_irq, "level");
>  		irq_set_status_flags(irq, IRQ_LEVEL);
>  	}
> +	irq_set_chip_data(irq, local_intc);
>  	return 0;
>  }
>  
> @@ -138,11 +154,13 @@ static const struct irq_domain_ops xintc_irq_domain_ops = {
>  static void xil_intc_irq_handler(struct irq_desc *desc)
>  {
>  	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	struct xintc_irq_chip *local_intc =
> +		irq_data_get_irq_handler_data(&desc->irq_data);
>  	u32 pending;
>  
>  	chained_irq_enter(chip, desc);
>  	do {
> -		pending = xintc_get_irq();
> +		pending = xintc_get_irq_local(local_intc);
>  		if (pending == -1U)
>  			break;
>  		generic_handle_irq(pending);
> @@ -153,28 +171,20 @@ static void xil_intc_irq_handler(struct irq_desc *desc)
>  static int __init xilinx_intc_of_init(struct device_node *intc,
>  					     struct device_node *parent)
>  {
> -	u32 nr_irq;
>  	int ret, irq;
>  	struct xintc_irq_chip *irqc;
> -
> -	if (xintc_irqc) {
> -		pr_err("irq-xilinx: Multiple instances aren't supported\n");
> -		return -EINVAL;
> -	}
> +	struct irq_chip *intc_dev;
>  
>  	irqc = kzalloc(sizeof(*irqc), GFP_KERNEL);
>  	if (!irqc)
>  		return -ENOMEM;
> -
> -	xintc_irqc = irqc;
> -
>  	irqc->base = of_iomap(intc, 0);
>  	BUG_ON(!irqc->base);
>  
> -	ret = of_property_read_u32(intc, "xlnx,num-intr-inputs", &nr_irq);
> +	ret = of_property_read_u32(intc, "xlnx,num-intr-inputs", &irqc->nr_irq);
>  	if (ret < 0) {
>  		pr_err("irq-xilinx: unable to read xlnx,num-intr-inputs\n");
> -		goto err_alloc;
> +		goto error;
>  	}
>  
>  	ret = of_property_read_u32(intc, "xlnx,kind-of-intr", &irqc->intr_mask);
> @@ -183,30 +193,42 @@ static int __init xilinx_intc_of_init(struct device_node *intc,
>  		irqc->intr_mask = 0;
>  	}
>  
> -	if (irqc->intr_mask >> nr_irq)
> +	if (irqc->intr_mask >> irqc->nr_irq)
>  		pr_warn("irq-xilinx: mismatch in kind-of-intr param\n");
>  
>  	pr_info("irq-xilinx: %pOF: num_irq=%d, edge=0x%x\n",
> -		intc, nr_irq, irqc->intr_mask);
> +		intc, irqc->nr_irq, irqc->intr_mask);
> +
> +	intc_dev = kzalloc(sizeof(*intc_dev), GFP_KERNEL);
> +	if (!intc_dev) {
> +		ret = -ENOMEM;
> +		goto error;
> +	}
>  
> +	intc_dev->name = intc->full_name;
> +	intc_dev->irq_unmask = intc_enable_or_unmask,
> +	intc_dev->irq_mask = intc_disable_or_mask,
> +	intc_dev->irq_ack = intc_ack,
> +	intc_dev->irq_mask_ack = intc_mask_ack,
> +	irqc->intc_dev = intc_dev;
>  
>  	/*
>  	 * Disable all external interrupts until they are
>  	 * explicity requested.
>  	 */
> -	xintc_write(IER, 0);
> +	xintc_write(irqc->base + IER, 0);
>  
>  	/* Acknowledge any pending interrupts just in case. */
> -	xintc_write(IAR, 0xffffffff);
> +	xintc_write(irqc->base + IAR, 0xffffffff);
>  
>  	/* Turn on the Master Enable. */
> -	xintc_write(MER, MER_HIE | MER_ME);
> -	if (!(xintc_read(MER) & (MER_HIE | MER_ME))) {
> +	xintc_write(irqc->base + MER, MER_HIE | MER_ME);
> +	if (!(xintc_read(irqc->base + MER) & (MER_HIE | MER_ME))) {
>  		static_branch_enable(&xintc_is_be);
> -		xintc_write(MER, MER_HIE | MER_ME);
> +		xintc_write(irqc->base + MER, MER_HIE | MER_ME);
>  	}
>  
> -	irqc->root_domain = irq_domain_add_linear(intc, nr_irq,
> +	irqc->root_domain = irq_domain_add_linear(intc, irqc->nr_irq,
>  						  &xintc_irq_domain_ops, irqc);
>  	if (!irqc->root_domain) {
>  		pr_err("irq-xilinx: Unable to create IRQ domain\n");
> @@ -225,13 +247,16 @@ static int __init xilinx_intc_of_init(struct device_node *intc,
>  			goto err_alloc;
>  		}
>  	} else {
> -		irq_set_default_host(irqc->root_domain);
> +		primary_intc = irqc;
> +		irq_set_default_host(primary_intc->root_domain);
>  	}
>  
>  	return 0;
>  
>  err_alloc:
> -	xintc_irqc = NULL;
> +	kfree(intc_dev);
> +error:
> +	iounmap(irqc->base);
>  	kfree(irqc);
>  	return ret;
>  
> 

Thanks,
Michal