arch/arm/plat-s3c64xx/irq.c

   1 /* arch/arm/plat-s3c64xx/irq.c
   2  *
   3  * Copyright 2008 Openmoko, Inc.
   4  * Copyright 2008 Simtec Electronics
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *      http://armlinux.simtec.co.uk/
   7  *
   8  * S3C64XX - Interrupt handling
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/serial_core.h>
  18 #include <linux/irq.h>
  19 #include <linux/io.h>
  20
  21 #include <asm/hardware/vic.h>
  22
  23 #include <mach/map.h>
  24 #include <plat/regs-serial.h>
  25 #include <plat/regs-timer.h>
  26 #include <plat/cpu.h>
  27
  28 /* Timer interrupt handling */
  29
  30 static void s3c_irq_demux_timer(unsigned int base_irq, unsigned int sub_irq)
  31 {
  32         generic_handle_irq(sub_irq);
  33 }
  34
  35 static void s3c_irq_demux_timer0(unsigned int irq, struct irq_desc *desc)
  36 {
  37         s3c_irq_demux_timer(irq, IRQ_TIMER0);
  38 }
  39
  40 static void s3c_irq_demux_timer1(unsigned int irq, struct irq_desc *desc)
  41 {
  42         s3c_irq_demux_timer(irq, IRQ_TIMER1);
  43 }
  44
  45 static void s3c_irq_demux_timer2(unsigned int irq, struct irq_desc *desc)
  46 {
  47         s3c_irq_demux_timer(irq, IRQ_TIMER2);
  48 }
  49
  50 static void s3c_irq_demux_timer3(unsigned int irq, struct irq_desc *desc)
  51 {
  52         s3c_irq_demux_timer(irq, IRQ_TIMER3);
  53 }
  54
  55 static void s3c_irq_demux_timer4(unsigned int irq, struct irq_desc *desc)
  56 {
  57         s3c_irq_demux_timer(irq, IRQ_TIMER4);
  58 }
  59
  60 /* We assume the IRQ_TIMER0..IRQ_TIMER4 range is continuous. */
  61
  62 static void s3c_irq_timer_mask(unsigned int irq)
  63 {
  64         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  65
  66         reg &= 0x1f;  /* mask out pending interrupts */
  67         reg &= ~(1 << (irq - IRQ_TIMER0));
  68         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  69 }
  70
  71 static void s3c_irq_timer_unmask(unsigned int irq)
  72 {
  73         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  74
  75         reg &= 0x1f;  /* mask out pending interrupts */
  76         reg |= 1 << (irq - IRQ_TIMER0);
  77         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  78 }
  79
  80 static void s3c_irq_timer_ack(unsigned int irq)
  81 {
  82         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  83
  84         reg &= 0x1f;
  85         reg |= (1 << 5) << (irq - IRQ_TIMER0);
  86         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  87 }
  88
  89 static struct irq_chip s3c_irq_timer = {
  90         .name           = "s3c-timer",
  91         .mask           = s3c_irq_timer_mask,
  92         .unmask         = s3c_irq_timer_unmask,
  93         .ack            = s3c_irq_timer_ack,
  94 };
  95
  96 struct uart_irq {
  97         void __iomem    *regs;
  98         unsigned int     base_irq;
  99         unsigned int     parent_irq;
 100 };
 101
 102 /* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3]
 103  * are consecutive when looking up the interrupt in the demux routines.
 104  */
 105 static struct uart_irq uart_irqs[] = {
 106         [0] = {
 107                 .regs           = S3C_VA_UART0,
 108                 .base_irq       = IRQ_S3CUART_BASE0,
 109                 .parent_irq     = IRQ_UART0,
 110         },
 111         [1] = {
 112                 .regs           = S3C_VA_UART1,
 113                 .base_irq       = IRQ_S3CUART_BASE1,
 114                 .parent_irq     = IRQ_UART1,
 115         },
 116         [2] = {
 117                 .regs           = S3C_VA_UART2,
 118                 .base_irq       = IRQ_S3CUART_BASE2,
 119                 .parent_irq     = IRQ_UART2,
 120         },
 121         [3] = {
 122                 .regs           = S3C_VA_UART3,
 123                 .base_irq       = IRQ_S3CUART_BASE3,
 124                 .parent_irq     = IRQ_UART3,
 125         },
 126 };
 127
 128 static inline void __iomem *s3c_irq_uart_base(unsigned int irq)
 129 {
 130         struct uart_irq *uirq = get_irq_chip_data(irq);
 131         return uirq->regs;
 132 }
 133
 134 static inline unsigned int s3c_irq_uart_bit(unsigned int irq)
 135 {
 136         return irq & 3;
 137 }
 138
 139 /* UART interrupt registers, not worth adding to seperate include header */
 140
 141 static void s3c_irq_uart_mask(unsigned int irq)
 142 {
 143         void __iomem *regs = s3c_irq_uart_base(irq);
 144         unsigned int bit = s3c_irq_uart_bit(irq);
 145         u32 reg;
 146
 147         reg = __raw_readl(regs + S3C64XX_UINTM);
 148         reg |= (1 << bit);
 149         __raw_writel(reg, regs + S3C64XX_UINTM);
 150 }
 151
 152 static void s3c_irq_uart_maskack(unsigned int irq)
 153 {
 154         void __iomem *regs = s3c_irq_uart_base(irq);
 155         unsigned int bit = s3c_irq_uart_bit(irq);
 156         u32 reg;
 157
 158         reg = __raw_readl(regs + S3C64XX_UINTM);
 159         reg |= (1 << bit);
 160         __raw_writel(reg, regs + S3C64XX_UINTM);
 161         __raw_writel(1 << bit, regs + S3C64XX_UINTP);
 162 }
 163
 164 static void s3c_irq_uart_unmask(unsigned int irq)
 165 {
 166         void __iomem *regs = s3c_irq_uart_base(irq);
 167         unsigned int bit = s3c_irq_uart_bit(irq);
 168         u32 reg;
 169
 170         reg = __raw_readl(regs + S3C64XX_UINTM);
 171         reg &= ~(1 << bit);
 172         __raw_writel(reg, regs + S3C64XX_UINTM);
 173 }
 174
 175 static void s3c_irq_uart_ack(unsigned int irq)
 176 {
 177         void __iomem *regs = s3c_irq_uart_base(irq);
 178         unsigned int bit = s3c_irq_uart_bit(irq);
 179
 180         __raw_writel(1 << bit, regs + S3C64XX_UINTP);
 181 }
 182
 183 static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc)
 184 {
 185         struct uart_irq *uirq = &uart_irqs[irq - IRQ_UART0];
 186         u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP);
 187         int base = uirq->base_irq;
 188
 189         if (pend & (1 << 0))
 190                 generic_handle_irq(base);
 191         if (pend & (1 << 1))
 192                 generic_handle_irq(base + 1);
 193         if (pend & (1 << 2))
 194                 generic_handle_irq(base + 2);
 195         if (pend & (1 << 3))
 196                 generic_handle_irq(base + 3);
 197 }
 198
 199 static struct irq_chip s3c_irq_uart = {
 200         .name           = "s3c-uart",
 201         .mask           = s3c_irq_uart_mask,
 202         .unmask         = s3c_irq_uart_unmask,
 203         .mask_ack       = s3c_irq_uart_maskack,
 204         .ack            = s3c_irq_uart_ack,
 205 };
 206
 207 static void __init s3c64xx_uart_irq(struct uart_irq *uirq)
 208 {
 209         void __iomem *reg_base = uirq->regs;
 210         unsigned int irq;
 211         int offs;
 212
 213         /* mask all interrupts at the start. */
 214         __raw_writel(0xf, reg_base + S3C64XX_UINTM);
 215
 216         for (offs = 0; offs < 3; offs++) {
 217                 irq = uirq->base_irq + offs;
 218
 219                 set_irq_chip(irq, &s3c_irq_uart);
 220                 set_irq_chip_data(irq, uirq);
 221                 set_irq_handler(irq, handle_level_irq);
 222                 set_irq_flags(irq, IRQF_VALID);
 223         }
 224
 225         set_irq_chained_handler(uirq->parent_irq, s3c_irq_demux_uart);
 226 }
 227
 228 void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid)
 229 {
 230         int uart, irq;
 231
 232         printk(KERN_DEBUG "%s: initialising interrupts\n", __func__);
 233
 234         /* initialise the pair of VICs */
 235         vic_init(S3C_VA_VIC0, S3C_VIC0_BASE, vic0_valid, 0);
 236         vic_init(S3C_VA_VIC1, S3C_VIC1_BASE, vic1_valid, 0);
 237
 238         /* add the timer sub-irqs */
 239
 240         set_irq_chained_handler(IRQ_TIMER0_VIC, s3c_irq_demux_timer0);
 241         set_irq_chained_handler(IRQ_TIMER1_VIC, s3c_irq_demux_timer1);
 242         set_irq_chained_handler(IRQ_TIMER2_VIC, s3c_irq_demux_timer2);
 243         set_irq_chained_handler(IRQ_TIMER3_VIC, s3c_irq_demux_timer3);
 244         set_irq_chained_handler(IRQ_TIMER4_VIC, s3c_irq_demux_timer4);
 245
 246         for (irq = IRQ_TIMER0; irq <= IRQ_TIMER4; irq++) {
 247                 set_irq_chip(irq, &s3c_irq_timer);
 248                 set_irq_handler(irq, handle_level_irq);
 249                 set_irq_flags(irq, IRQF_VALID);
 250         }
 251
 252         for (uart = 0; uart < ARRAY_SIZE(uart_irqs); uart++)
 253                 s3c64xx_uart_irq(&uart_irqs[uart]);
 254 }
 255
 256