On 14.11.2016 13:13, Zubair Lutfullah Kakakhel wrote:
> Add a global structure to house various variables.
> And cleanup read/write handling by using jump label api.
>
> Signed-off-by: Zubair Lutfullah Kakakhel <zubair.kakak...@imgtec.com>
>
> ---
> V6 -> V7
> Restructure and use jump label api
> Better commit log
>
> V5 -> V6
> Removed __func__ from printk
> Rebase to v4.9-rc3
>
> V4 -> V5
> Rebased to v4.9-rc1
> Better error handling
>
> V3 -> V4
> Better error handling for kzalloc
> Erroring out if the axi intc is probed twice as that isn't
> supported
>
> V2 -> V3
> New patch. Cleans up driver structure
> ---
> drivers/irqchip/irq-xilinx-intc.c | 118
> +++++++++++++++++++++-----------------
> 1 file changed, 66 insertions(+), 52 deletions(-)
>
> diff --git a/drivers/irqchip/irq-xilinx-intc.c
> b/drivers/irqchip/irq-xilinx-intc.c
> index 096c1ed..7331d8c 100644
> --- a/drivers/irqchip/irq-xilinx-intc.c
> +++ b/drivers/irqchip/irq-xilinx-intc.c
> @@ -14,10 +14,9 @@
> #include <linux/irqchip.h>
> #include <linux/of_address.h>
> #include <linux/io.h>
> +#include <linux/jump_label.h>
> #include <linux/bug.h>
>
> -static void __iomem *intc_baseaddr;
> -
> /* No one else should require these constants, so define them locally here.
> */
> #define ISR 0x00 /* Interrupt Status Register */
> #define IPR 0x04 /* Interrupt Pending Register */
> @@ -31,27 +30,30 @@ static void __iomem *intc_baseaddr;
> #define MER_ME (1<<0)
> #define MER_HIE (1<<1)
>
> -static unsigned int (*read_fn)(void __iomem *);
> -static void (*write_fn)(u32, void __iomem *);
> +static DEFINE_STATIC_KEY_FALSE(xintc_is_be);
>
> -static void intc_write32(u32 val, void __iomem *addr)
> -{
> - iowrite32(val, addr);
> -}
> +struct xintc_irq_chip {
> + void __iomem *base;
> + struct irq_domain *root_domain;
> + u32 intr_mask;
> +};
>
> -static unsigned int intc_read32(void __iomem *addr)
> -{
> - return ioread32(addr);
> -}
> +static struct xintc_irq_chip *xintc_irqc;
>
> -static void intc_write32_be(u32 val, void __iomem *addr)
> +static void xintc_write(int reg, u32 data)
> {
> - iowrite32be(val, addr);
> + if (static_branch_unlikely(&xintc_is_be))
> + iowrite32be(data, xintc_irqc->base + reg);
> + else
> + iowrite32(data, xintc_irqc->base + reg);
> }
>
> -static unsigned int intc_read32_be(void __iomem *addr)
> +static unsigned int xintc_read(int reg)
> {
> - return ioread32be(addr);
> + if (static_branch_unlikely(&xintc_is_be))
> + return ioread32be(xintc_irqc->base + reg);
> + else
> + return ioread32(xintc_irqc->base + reg);
> }
>
> static void intc_enable_or_unmask(struct irq_data *d)
> @@ -65,21 +67,21 @@ static void intc_enable_or_unmask(struct irq_data *d)
> * acks the irq before calling the interrupt handler
> */
> if (irqd_is_level_type(d))
> - write_fn(mask, intc_baseaddr + IAR);
> + xintc_write(IAR, mask);
>
> - write_fn(mask, intc_baseaddr + SIE);
> + xintc_write(SIE, mask);
> }
>
> static void intc_disable_or_mask(struct irq_data *d)
> {
> pr_debug("irq-xilinx: disable: %ld\n", d->hwirq);
> - write_fn(1 << d->hwirq, intc_baseaddr + CIE);
> + xintc_write(CIE, 1 << d->hwirq);
> }
>
> static void intc_ack(struct irq_data *d)
> {
> pr_debug("irq-xilinx: ack: %ld\n", d->hwirq);
> - write_fn(1 << d->hwirq, intc_baseaddr + IAR);
> + xintc_write(IAR, 1 << d->hwirq);
> }
>
> static void intc_mask_ack(struct irq_data *d)
> @@ -87,8 +89,8 @@ static void intc_mask_ack(struct irq_data *d)
> unsigned long mask = 1 << d->hwirq;
>
> pr_debug("irq-xilinx: disable_and_ack: %ld\n", d->hwirq);
> - write_fn(mask, intc_baseaddr + CIE);
> - write_fn(mask, intc_baseaddr + IAR);
> + xintc_write(CIE, mask);
> + xintc_write(IAR, mask);
> }
>
> static struct irq_chip intc_dev = {
> @@ -99,15 +101,13 @@ static struct irq_chip intc_dev = {
> .irq_mask_ack = intc_mask_ack,
> };
>
> -static struct irq_domain *root_domain;
> -
> unsigned int get_irq(void)
> {
> unsigned int hwirq, irq = -1;
>
> - hwirq = read_fn(intc_baseaddr + IVR);
> + hwirq = xintc_read(IVR);
> if (hwirq != -1U)
> - irq = irq_find_mapping(root_domain, hwirq);
> + irq = irq_find_mapping(xintc_irqc->root_domain, hwirq);
>
> pr_debug("irq-xilinx: hwirq=%d, irq=%d\n", hwirq, irq);
>
> @@ -116,9 +116,7 @@ unsigned int get_irq(void)
>
> static int xintc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t
> hw)
> {
> - u32 intr_mask = (u32)d->host_data;
> -
> - if (intr_mask & (1 << hw)) {
> + if (xintc_irqc->intr_mask & (1 << hw)) {
> irq_set_chip_and_handler_name(irq, &intc_dev,
> handle_edge_irq, "edge");
> irq_clear_status_flags(irq, IRQ_LEVEL);
> @@ -138,59 +136,75 @@ static const struct irq_domain_ops xintc_irq_domain_ops
> = {
> static int __init xilinx_intc_of_init(struct device_node *intc,
> struct device_node *parent)
> {
> - u32 nr_irq, intr_mask;
> + u32 nr_irq;
> int ret;
> + struct xintc_irq_chip *irqc;
>
> - intc_baseaddr = of_iomap(intc, 0);
> - BUG_ON(!intc_baseaddr);
> + if (xintc_irqc) {
> + pr_err("irq-xilinx: Multiple instances aren't supported\n");
> + return -EINVAL;
> + }
I don't agree with this.
Pretty long time ago we were added support for multiple instances in
xilinx private tree.
You can look here.
https://github.com/Xilinx/linux-xlnx/blob/master/drivers/irqchip/irq-xilinx-intc.c
Not sure if this the latest way how to do it but as you can see
we were setting up
irq_set_handler_data(irq, intc);
and then when you need that structure we were calling
struct intc *local_intc = irq_data_get_irq_chip_data(d);
And that should be it to support multiple instance of this driver.
Based on 5/7 you are describing your interrupt subsystem like this.
Peripherals --> xilinx_intcontroller -> mips_cpu_int controller
If mips_cpu_int has more than one input you can connect more xilinx intc
controllers.
If not you still have an option to connect
xilinx_intcontroller(up to 32 peripherals) -> xilinx_intcontroller(one
intc + up to 31 peripherals) -> mips_cpu_int controller
Thanks,
Michal
