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/irq.h>
  18 #include <linux/io.h>
  19
  20 #include <asm/hardware/vic.h>
  21
  22 #include <mach/map.h>
  23 #include <plat/regs-timer.h>
  24 #include <plat/cpu.h>
  25
  26 /* Timer interrupt handling */
  27
  28 static void s3c_irq_demux_timer(unsigned int base_irq, unsigned int sub_irq)
  29 {
  30         generic_handle_irq(sub_irq);
  31 }
  32
  33 static void s3c_irq_demux_timer0(unsigned int irq, struct irq_desc *desc)
  34 {
  35         s3c_irq_demux_timer(irq, IRQ_TIMER0);
  36 }
  37
  38 static void s3c_irq_demux_timer1(unsigned int irq, struct irq_desc *desc)
  39 {
  40         s3c_irq_demux_timer(irq, IRQ_TIMER1);
  41 }
  42
  43 static void s3c_irq_demux_timer2(unsigned int irq, struct irq_desc *desc)
  44 {
  45         s3c_irq_demux_timer(irq, IRQ_TIMER2);
  46 }
  47
  48 static void s3c_irq_demux_timer3(unsigned int irq, struct irq_desc *desc)
  49 {
  50         s3c_irq_demux_timer(irq, IRQ_TIMER3);
  51 }
  52
  53 static void s3c_irq_demux_timer4(unsigned int irq, struct irq_desc *desc)
  54 {
  55         s3c_irq_demux_timer(irq, IRQ_TIMER4);
  56 }
  57
  58 /* We assume the IRQ_TIMER0..IRQ_TIMER4 range is continuous. */
  59
  60 static void s3c_irq_timer_mask(unsigned int irq)
  61 {
  62         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  63
  64         reg &= 0x1f;  /* mask out pending interrupts */
  65         reg &= ~(1 << (irq - IRQ_TIMER0));
  66         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  67 }
  68
  69 static void s3c_irq_timer_unmask(unsigned int irq)
  70 {
  71         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  72
  73         reg &= 0x1f;  /* mask out pending interrupts */
  74         reg |= 1 << (irq - IRQ_TIMER0);
  75         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  76 }
  77
  78 static void s3c_irq_timer_ack(unsigned int irq)
  79 {
  80         u32 reg = __raw_readl(S3C64XX_TINT_CSTAT);
  81
  82         reg &= 0x1f;
  83         reg |= (1 << 5) << (irq - IRQ_TIMER0);
  84         __raw_writel(reg, S3C64XX_TINT_CSTAT);
  85 }
  86
  87 static struct irq_chip s3c_irq_timer = {
  88         .name           = "s3c-timer",
  89         .mask           = s3c_irq_timer_mask,
  90         .unmask         = s3c_irq_timer_unmask,
  91         .ack            = s3c_irq_timer_ack,
  92 };
  93
  94 struct uart_irq {
  95         void __iomem    *regs;
  96         unsigned int     base_irq;
  97         unsigned int     parent_irq;
  98 };
  99
 100 /* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3]
 101  * are consecutive when looking up the interrupt in the demux routines.
 102  */
 103 static struct uart_irq uart_irqs[] = {
 104         [0] = {
 105                 .regs           = S3C_VA_UART0,
 106                 .base_irq       = IRQ_S3CUART_BASE0,
 107                 .parent_irq     = IRQ_UART0,
 108         },
 109         [1] = {
 110                 .regs           = S3C_VA_UART1,
 111                 .base_irq       = IRQ_S3CUART_BASE1,
 112                 .parent_irq     = IRQ_UART1,
 113         },
 114         [2] = {
 115                 .regs           = S3C_VA_UART2,
 116                 .base_irq       = IRQ_S3CUART_BASE2,
 117                 .parent_irq     = IRQ_UART2,
 118         },
 119         [3] = {
 120                 .regs           = S3C_VA_UART3,
 121                 .base_irq       = IRQ_S3CUART_BASE3,
 122                 .parent_irq     = IRQ_UART3,
 123         },
 124 };
 125
 126 static inline void __iomem *s3c_irq_uart_base(unsigned int irq)
 127 {
 128         struct uart_irq *uirq = get_irq_chip_data(irq);
 129         return uirq->regs;
 130 }
 131
 132 static inline unsigned int s3c_irq_uart_bit(unsigned int irq)
 133 {
 134         return irq & 3;
 135 }
 136
 137 /* UART interrupt registers, not worth adding to seperate include header */
 138 #define S3C64XX_UINTP   0x30
 139 #define S3C64XX_UINTSP  0x34
 140 #define S3C64XX_UINTM   0x38
 141
 142 static void s3c_irq_uart_mask(unsigned int irq)
 143 {
 144         void __iomem *regs = s3c_irq_uart_base(irq);
 145         unsigned int bit = s3c_irq_uart_bit(irq);
 146         u32 reg;
 147
 148         reg = __raw_readl(regs + S3C64XX_UINTM);
 149         reg |= (1 << bit);
 150         __raw_writel(reg, regs + S3C64XX_UINTM);
 151 }
 152
 153 static void s3c_irq_uart_maskack(unsigned int irq)
 154 {
 155         void __iomem *regs = s3c_irq_uart_base(irq);
 156         unsigned int bit = s3c_irq_uart_bit(irq);
 157         u32 reg;
 158
 159         reg = __raw_readl(regs + S3C64XX_UINTM);
 160         reg |= (1 << bit);
 161         __raw_writel(reg, regs + S3C64XX_UINTM);
 162         __raw_writel(1 << bit, regs + S3C64XX_UINTP);
 163 }
 164
 165 static void s3c_irq_uart_unmask(unsigned int irq)
 166 {
 167         void __iomem *regs = s3c_irq_uart_base(irq);
 168         unsigned int bit = s3c_irq_uart_bit(irq);
 169         u32 reg;
 170
 171         reg = __raw_readl(regs + S3C64XX_UINTM);
 172         reg &= ~(1 << bit);
 173         __raw_writel(reg, regs + S3C64XX_UINTM);
 174 }
 175
 176 static void s3c_irq_uart_ack(unsigned int irq)
 177 {
 178         void __iomem *regs = s3c_irq_uart_base(irq);
 179         unsigned int bit = s3c_irq_uart_bit(irq);
 180
 181         __raw_writel(1 << bit, regs + S3C64XX_UINTP);
 182 }
 183
 184 static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc)
 185 {
 186         struct uart_irq *uirq = &uart_irqs[irq - IRQ_UART0];
 187         u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP);
 188         int base = uirq->base_irq;
 189
 190         if (pend & (1 << 0))
 191                 generic_handle_irq(base);
 192         if (pend & (1 << 1))
 193                 generic_handle_irq(base + 1);
 194         if (pend & (1 << 2))
 195                 generic_handle_irq(base + 2);
 196         if (pend & (1 << 3))
 197                 generic_handle_irq(base + 3);
 198 }
 199
 200 static struct irq_chip s3c_irq_uart = {
 201         .name           = "s3c-uart",
 202         .mask           = s3c_irq_uart_mask,
 203         .unmask         = s3c_irq_uart_unmask,
 204         .mask_ack       = s3c_irq_uart_maskack,
 205         .ack            = s3c_irq_uart_ack,
 206 };
 207
 208 static void __init s3c64xx_uart_irq(struct uart_irq *uirq)
 209 {
 210         void *reg_base = uirq->regs;
 211         unsigned int irq;
 212         int offs;
 213
 214         /* mask all interrupts at the start. */
 215         __raw_writel(0xf, reg_base + S3C64XX_UINTM);
 216
 217         for (offs = 0; offs < 3; offs++) {
 218                 irq = uirq->base_irq + offs;
 219
 220                 set_irq_chip(irq, &s3c_irq_uart);
 221                 set_irq_chip_data(irq, uirq);
 222                 set_irq_handler(irq, handle_level_irq);
 223                 set_irq_flags(irq, IRQF_VALID);
 224         }
 225
 226         set_irq_chained_handler(uirq->parent_irq, s3c_irq_demux_uart);
 227 }
 228
 229 void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid)
 230 {
 231         int uart, irq;
 232
 233         printk(KERN_DEBUG "%s: initialising interrupts\n", __func__);
 234
 235         /* initialise the pair of VICs */
 236         vic_init(S3C_VA_VIC0, S3C_VIC0_BASE, vic0_valid);
 237         vic_init(S3C_VA_VIC1, S3C_VIC1_BASE, vic1_valid);
 238
 239         /* add the timer sub-irqs */
 240
 241         set_irq_chained_handler(IRQ_TIMER0_VIC, s3c_irq_demux_timer0);
 242         set_irq_chained_handler(IRQ_TIMER1_VIC, s3c_irq_demux_timer1);
 243         set_irq_chained_handler(IRQ_TIMER2_VIC, s3c_irq_demux_timer2);
 244         set_irq_chained_handler(IRQ_TIMER3_VIC, s3c_irq_demux_timer3);
 245         set_irq_chained_handler(IRQ_TIMER4_VIC, s3c_irq_demux_timer4);
 246
 247         for (irq = IRQ_TIMER0; irq <= IRQ_TIMER4; irq++) {
 248                 set_irq_chip(irq, &s3c_irq_timer);
 249                 set_irq_handler(irq, handle_level_irq);
 250                 set_irq_flags(irq, IRQF_VALID);
 251         }
 252
 253         for (uart = 0; uart < ARRAY_SIZE(uart_irqs); uart++)
 254                 s3c64xx_uart_irq(&uart_irqs[uart]);
 255 }
 256
 257