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

From: Michal Simek
Date: Wed Feb 05 2020 - 09:54:00 EST


Hi Mubin,

On 05. 02. 20 15:05, Mubin Usman Sayyed wrote:
> From: Mubin Sayyed <mubin.usman.sayyed@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>
> Signed-off-by: Mubin Sayyed <mubin.usman.sayyed@xxxxxxxxxx>
> ---
> 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