From 3e694d4bc633a5e6192e63a644a628e7bbab3e64 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Tue, 21 Oct 2008 14:07:05 +0100 Subject: [PATCH] [ARM] S3C64XX: Demux UART interrupts Add demux handling for the UART interrupts generated by the VIC into their seperate IRQs that the serial driver can register. Signed-off-by: Ben Dooks --- arch/arm/mach-s3c6400/include/mach/map.h | 8 ++ arch/arm/plat-s3c64xx/irq.c | 140 ++++++++++++++++++++++- 2 files changed, 147 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-s3c6400/include/mach/map.h b/arch/arm/mach-s3c6400/include/mach/map.h index de6cdd518cea..83ed3c158693 100644 --- a/arch/arm/mach-s3c6400/include/mach/map.h +++ b/arch/arm/mach-s3c6400/include/mach/map.h @@ -24,6 +24,14 @@ #define S3C_PA_UART3 (S3C_PA_UART + 0xC00) #define S3C_UART_OFFSET (0x400) +/* See notes on UART VA mapping in debug-macro.S */ +#define S3C_VA_UARTx(x) (S3C_VA_UART + (S3C_PA_UART & 0xfffff) + ((x) * S3C_UART_OFFSET)) + +#define S3C_VA_UART0 S3C_VA_UARTx(0) +#define S3C_VA_UART1 S3C_VA_UARTx(1) +#define S3C_VA_UART2 S3C_VA_UARTx(2) +#define S3C_VA_UART3 S3C_VA_UARTx(3) + #define S3C64XX_PA_SYSCON (0x7E00F000) #define S3C64XX_PA_TIMER (0x7F006000) diff --git a/arch/arm/plat-s3c64xx/irq.c b/arch/arm/plat-s3c64xx/irq.c index 1e6fa5c828c9..99df9dbefa69 100644 --- a/arch/arm/plat-s3c64xx/irq.c +++ b/arch/arm/plat-s3c64xx/irq.c @@ -91,9 +91,144 @@ static struct irq_chip s3c_irq_timer = { .ack = s3c_irq_timer_ack, }; +struct uart_irq { + void __iomem *regs; + unsigned int base_irq; + unsigned int parent_irq; +}; + +/* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3] + * are consecutive when looking up the interrupt in the demux routines. + */ +static struct uart_irq uart_irqs[] = { + [0] = { + .regs = S3C_VA_UART0, + .base_irq = IRQ_S3CUART_BASE0, + .parent_irq = IRQ_UART0, + }, + [1] = { + .regs = S3C_VA_UART1, + .base_irq = IRQ_S3CUART_BASE1, + .parent_irq = IRQ_UART1, + }, + [2] = { + .regs = S3C_VA_UART2, + .base_irq = IRQ_S3CUART_BASE2, + .parent_irq = IRQ_UART2, + }, + [3] = { + .regs = S3C_VA_UART3, + .base_irq = IRQ_S3CUART_BASE3, + .parent_irq = IRQ_UART3, + }, +}; + +static inline void __iomem *s3c_irq_uart_base(unsigned int irq) +{ + struct uart_irq *uirq = get_irq_chip_data(irq); + return uirq->regs; +} + +static inline unsigned int s3c_irq_uart_bit(unsigned int irq) +{ + return irq & 3; +} + +/* UART interrupt registers, not worth adding to seperate include header */ +#define S3C64XX_UINTP 0x30 +#define S3C64XX_UINTSP 0x34 +#define S3C64XX_UINTM 0x38 + +static void s3c_irq_uart_mask(unsigned int irq) +{ + void __iomem *regs = s3c_irq_uart_base(irq); + unsigned int bit = s3c_irq_uart_bit(irq); + u32 reg; + + reg = __raw_readl(regs + S3C64XX_UINTM); + reg |= (1 << bit); + __raw_writel(reg, regs + S3C64XX_UINTM); +} + +static void s3c_irq_uart_maskack(unsigned int irq) +{ + void __iomem *regs = s3c_irq_uart_base(irq); + unsigned int bit = s3c_irq_uart_bit(irq); + u32 reg; + + reg = __raw_readl(regs + S3C64XX_UINTM); + reg |= (1 << bit); + __raw_writel(reg, regs + S3C64XX_UINTM); + __raw_writel(1 << bit, regs + S3C64XX_UINTP); +} + +static void s3c_irq_uart_unmask(unsigned int irq) +{ + void __iomem *regs = s3c_irq_uart_base(irq); + unsigned int bit = s3c_irq_uart_bit(irq); + u32 reg; + + reg = __raw_readl(regs + S3C64XX_UINTM); + reg &= ~(1 << bit); + __raw_writel(reg, regs + S3C64XX_UINTM); +} + +static void s3c_irq_uart_ack(unsigned int irq) +{ + void __iomem *regs = s3c_irq_uart_base(irq); + unsigned int bit = s3c_irq_uart_bit(irq); + + __raw_writel(1 << bit, regs + S3C64XX_UINTP); +} + +static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc) +{ + struct uart_irq *uirq = &uart_irqs[irq - IRQ_UART0]; + u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP); + int base = uirq->base_irq; + + if (pend & (1 << 0)) + generic_handle_irq(base); + if (pend & (1 << 1)) + generic_handle_irq(base + 1); + if (pend & (1 << 2)) + generic_handle_irq(base + 2); + if (pend & (1 << 3)) + generic_handle_irq(base + 3); +} + +static struct irq_chip s3c_irq_uart = { + .name = "s3c-uart", + .mask = s3c_irq_uart_mask, + .unmask = s3c_irq_uart_unmask, + .mask_ack = s3c_irq_uart_maskack, + .ack = s3c_irq_uart_ack, +}; + +static void __init s3c64xx_uart_irq(struct uart_irq *uirq) +{ + void *reg_base = uirq->regs; + unsigned int irq; + int offs; + + /* mask all interrupts at the start. */ + __raw_writel(0xf, reg_base + S3C64XX_UINTM); + + for (offs = 0; offs < 3; offs++) { + irq = uirq->base_irq + offs; + + set_irq_chip(irq, &s3c_irq_uart); + set_irq_chip_data(irq, uirq); + set_irq_handler(irq, handle_level_irq); + set_irq_flags(irq, IRQF_VALID); + } + + set_irq_chained_handler(uirq->parent_irq, s3c_irq_demux_uart); +} + void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid) { - int irq; + int uart, irq; printk(KERN_INFO "%s: initialising interrupts\n", __func__); @@ -114,6 +249,9 @@ void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid) set_irq_handler(irq, handle_level_irq); set_irq_flags(irq, IRQF_VALID); } + + for (uart = 0; uart < ARRAY_SIZE(uart_irqs); uart++) + s3c64xx_uart_irq(&uart_irqs[uart]); } -- 2.30.2