From 4a040b406e3cbbc19f90c086a489744f1d0879cc Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Thu, 23 Mar 2017 16:34:46 +0000 Subject: [PATCH] bcm2835-aux: Add aux interrupt controller The AUX block has a shared interrupt line with a register indicating which devices have active IRQs. Expose this as a nested interrupt controller to avoid sharing problems. See: https://github.com/raspberrypi/linux/issues/1484 https://github.com/raspberrypi/linux/issues/1573 Signed-off-by: Phil Elwell Signed-off-by: Tim Gardner --- drivers/clk/bcm/clk-bcm2835-aux.c | 120 ++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) diff --git a/drivers/clk/bcm/clk-bcm2835-aux.c b/drivers/clk/bcm/clk-bcm2835-aux.c index bd750cf2238d..41e0702fae46 100644 --- a/drivers/clk/bcm/clk-bcm2835-aux.c +++ b/drivers/clk/bcm/clk-bcm2835-aux.c @@ -17,17 +17,107 @@ #include #include #include +#include +#include +#include #include #define BCM2835_AUXIRQ 0x00 #define BCM2835_AUXENB 0x04 +#define BCM2835_AUXIRQ_NUM_IRQS 3 + +#define BCM2835_AUXIRQ_UART_IRQ 0 +#define BCM2835_AUXIRQ_SPI1_IRQ 1 +#define BCM2835_AUXIRQ_SPI2_IRQ 2 + +#define BCM2835_AUXIRQ_UART_MASK 0x01 +#define BCM2835_AUXIRQ_SPI1_MASK 0x02 +#define BCM2835_AUXIRQ_SPI2_MASK 0x04 + +#define BCM2835_AUXIRQ_ALL_MASK \ + (BCM2835_AUXIRQ_UART_MASK | \ + BCM2835_AUXIRQ_SPI1_MASK | \ + BCM2835_AUXIRQ_SPI2_MASK) + +struct auxirq_state { + void __iomem *status; + u32 enables; + struct irq_domain *domain; + struct regmap *local_regmap; +}; + +static struct auxirq_state auxirq __read_mostly; + +static irqreturn_t bcm2835_auxirq_handler(int irq, void *dev_id) +{ + u32 stat = readl_relaxed(auxirq.status); + u32 masked = stat & auxirq.enables; + + if (masked & BCM2835_AUXIRQ_UART_MASK) + generic_handle_irq(irq_linear_revmap(auxirq.domain, + BCM2835_AUXIRQ_UART_IRQ)); + + if (masked & BCM2835_AUXIRQ_SPI1_MASK) + generic_handle_irq(irq_linear_revmap(auxirq.domain, + BCM2835_AUXIRQ_SPI1_IRQ)); + + if (masked & BCM2835_AUXIRQ_SPI2_MASK) + generic_handle_irq(irq_linear_revmap(auxirq.domain, + BCM2835_AUXIRQ_SPI2_IRQ)); + + return (masked & BCM2835_AUXIRQ_ALL_MASK) ? IRQ_HANDLED : IRQ_NONE; +} + +static int bcm2835_auxirq_xlate(struct irq_domain *d, + struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, + unsigned int *out_type) +{ + if (WARN_ON(intsize != 1)) + return -EINVAL; + + if (WARN_ON(intspec[0] >= BCM2835_AUXIRQ_NUM_IRQS)) + return -EINVAL; + + *out_hwirq = intspec[0]; + *out_type = IRQ_TYPE_NONE; + return 0; +} + +static void bcm2835_auxirq_mask(struct irq_data *data) +{ + irq_hw_number_t hwirq = irqd_to_hwirq(data); + + auxirq.enables &= ~(1 << hwirq); +} + +static void bcm2835_auxirq_unmask(struct irq_data *data) +{ + irq_hw_number_t hwirq = irqd_to_hwirq(data); + + auxirq.enables |= (1 << hwirq); +} + +static struct irq_chip bcm2835_auxirq_chip = { + .name = "bcm2835-auxirq", + .irq_mask = bcm2835_auxirq_mask, + .irq_unmask = bcm2835_auxirq_unmask, +}; + +static const struct irq_domain_ops bcm2835_auxirq_ops = { + .xlate = bcm2835_auxirq_xlate//irq_domain_xlate_onecell +}; + static int bcm2835_aux_clk_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node; struct clk_hw_onecell_data *onecell; const char *parent; struct clk *parent_clk; + int parent_irq; struct resource *res; void __iomem *reg, *gate; @@ -41,6 +131,36 @@ static int bcm2835_aux_clk_probe(struct platform_device *pdev) if (IS_ERR(reg)) return PTR_ERR(reg); + parent_irq = irq_of_parse_and_map(node, 0); + if (parent_irq) { + int ret; + int i; + + /* Manage the AUX irq as well */ + auxirq.status = reg + BCM2835_AUXIRQ; + auxirq.domain = irq_domain_add_linear(node, + BCM2835_AUXIRQ_NUM_IRQS, + &bcm2835_auxirq_ops, + NULL); + if (!auxirq.domain) + return -ENXIO; + + for (i = 0; i < BCM2835_AUXIRQ_NUM_IRQS; i++) { + unsigned int irq = irq_create_mapping(auxirq.domain, i); + + if (irq == 0) + return -ENXIO; + + irq_set_chip_and_handler(irq, &bcm2835_auxirq_chip, + handle_level_irq); + } + + ret = devm_request_irq(dev, parent_irq, bcm2835_auxirq_handler, + 0, "bcm2835-auxirq", NULL); + if (ret) + return ret; + } + onecell = devm_kmalloc(dev, sizeof(*onecell) + sizeof(*onecell->hws) * BCM2835_AUX_CLOCK_COUNT, GFP_KERNEL); if (!onecell) -- 2.39.2