2 * linux/arch/arm/mach-versatile/core.c
4 * Copyright (C) 1999 - 2003 ARM Limited
5 * Copyright (C) 2000 Deep Blue Solutions Ltd
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <linux/init.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/platform_device.h>
25 #include <linux/sysdev.h>
26 #include <linux/interrupt.h>
27 #include <linux/amba/bus.h>
28 #include <linux/amba/clcd.h>
30 #include <asm/system.h>
31 #include <asm/hardware.h>
35 #include <asm/hardware/arm_timer.h>
36 #include <asm/hardware/icst307.h>
37 #include <asm/hardware/vic.h>
38 #include <asm/mach-types.h>
40 #include <asm/mach/arch.h>
41 #include <asm/mach/flash.h>
42 #include <asm/mach/irq.h>
43 #include <asm/mach/time.h>
44 #include <asm/mach/map.h>
45 #include <asm/mach/mmc.h>
51 * All IO addresses are mapped onto VA 0xFFFx.xxxx, where x.xxxx
54 * Setup a VA for the Versatile Vectored Interrupt Controller.
56 #define __io_address(n) __io(IO_ADDRESS(n))
57 #define VA_VIC_BASE __io_address(VERSATILE_VIC_BASE)
58 #define VA_SIC_BASE __io_address(VERSATILE_SIC_BASE)
60 static void sic_mask_irq(unsigned int irq)
63 writel(1 << irq, VA_SIC_BASE + SIC_IRQ_ENABLE_CLEAR);
66 static void sic_unmask_irq(unsigned int irq)
69 writel(1 << irq, VA_SIC_BASE + SIC_IRQ_ENABLE_SET);
72 static struct irqchip sic_chip = {
75 .unmask = sic_unmask_irq,
79 sic_handle_irq(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
81 unsigned long status = readl(VA_SIC_BASE + SIC_IRQ_STATUS);
84 do_bad_IRQ(irq, desc, regs);
89 irq = ffs(status) - 1;
90 status &= ~(1 << irq);
94 desc = irq_desc + irq;
95 desc_handle_irq(irq, desc, regs);
100 #define IRQ_MMCI0A IRQ_VICSOURCE22
101 #define IRQ_AACI IRQ_VICSOURCE24
102 #define IRQ_ETH IRQ_VICSOURCE25
103 #define PIC_MASK 0xFFD00000
105 #define IRQ_MMCI0A IRQ_SIC_MMCI0A
106 #define IRQ_AACI IRQ_SIC_AACI
107 #define IRQ_ETH IRQ_SIC_ETH
111 void __init versatile_init_irq(void)
115 vic_init(VA_VIC_BASE, IRQ_VIC_START, ~0);
117 set_irq_chained_handler(IRQ_VICSOURCE31, sic_handle_irq);
119 /* Do second interrupt controller */
120 writel(~0, VA_SIC_BASE + SIC_IRQ_ENABLE_CLEAR);
122 for (i = IRQ_SIC_START; i <= IRQ_SIC_END; i++) {
123 if ((PIC_MASK & (1 << (i - IRQ_SIC_START))) == 0) {
124 set_irq_chip(i, &sic_chip);
125 set_irq_handler(i, do_level_IRQ);
126 set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
131 * Interrupts on secondary controller from 0 to 8 are routed to
133 * Interrupts from 21 to 31 are routed directly to the VIC on
134 * the corresponding number on primary controller. This is controlled
135 * by setting PIC_ENABLEx.
137 writel(PIC_MASK, VA_SIC_BASE + SIC_INT_PIC_ENABLE);
140 static struct map_desc versatile_io_desc[] __initdata = {
142 .virtual = IO_ADDRESS(VERSATILE_SYS_BASE),
143 .pfn = __phys_to_pfn(VERSATILE_SYS_BASE),
147 .virtual = IO_ADDRESS(VERSATILE_SIC_BASE),
148 .pfn = __phys_to_pfn(VERSATILE_SIC_BASE),
152 .virtual = IO_ADDRESS(VERSATILE_VIC_BASE),
153 .pfn = __phys_to_pfn(VERSATILE_VIC_BASE),
157 .virtual = IO_ADDRESS(VERSATILE_SCTL_BASE),
158 .pfn = __phys_to_pfn(VERSATILE_SCTL_BASE),
162 #ifdef CONFIG_MACH_VERSATILE_AB
164 .virtual = IO_ADDRESS(VERSATILE_GPIO0_BASE),
165 .pfn = __phys_to_pfn(VERSATILE_GPIO0_BASE),
169 .virtual = IO_ADDRESS(VERSATILE_IB2_BASE),
170 .pfn = __phys_to_pfn(VERSATILE_IB2_BASE),
175 #ifdef CONFIG_DEBUG_LL
177 .virtual = IO_ADDRESS(VERSATILE_UART0_BASE),
178 .pfn = __phys_to_pfn(VERSATILE_UART0_BASE),
185 .virtual = IO_ADDRESS(VERSATILE_PCI_CORE_BASE),
186 .pfn = __phys_to_pfn(VERSATILE_PCI_CORE_BASE),
190 .virtual = VERSATILE_PCI_VIRT_BASE,
191 .pfn = __phys_to_pfn(VERSATILE_PCI_BASE),
192 .length = VERSATILE_PCI_BASE_SIZE,
195 .virtual = VERSATILE_PCI_CFG_VIRT_BASE,
196 .pfn = __phys_to_pfn(VERSATILE_PCI_CFG_BASE),
197 .length = VERSATILE_PCI_CFG_BASE_SIZE,
202 .virtual = VERSATILE_PCI_VIRT_MEM_BASE0,
203 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE0),
207 .virtual = VERSATILE_PCI_VIRT_MEM_BASE1,
208 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE1),
212 .virtual = VERSATILE_PCI_VIRT_MEM_BASE2,
213 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE2),
221 void __init versatile_map_io(void)
223 iotable_init(versatile_io_desc, ARRAY_SIZE(versatile_io_desc));
226 #define VERSATILE_REFCOUNTER (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_24MHz_OFFSET)
229 * This is the Versatile sched_clock implementation. This has
230 * a resolution of 41.7ns, and a maximum value of about 179s.
232 unsigned long long sched_clock(void)
234 unsigned long long v;
236 v = (unsigned long long)readl(VERSATILE_REFCOUNTER) * 125;
243 #define VERSATILE_FLASHCTRL (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_FLASH_OFFSET)
245 static int versatile_flash_init(void)
249 val = __raw_readl(VERSATILE_FLASHCTRL);
250 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
251 __raw_writel(val, VERSATILE_FLASHCTRL);
256 static void versatile_flash_exit(void)
260 val = __raw_readl(VERSATILE_FLASHCTRL);
261 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
262 __raw_writel(val, VERSATILE_FLASHCTRL);
265 static void versatile_flash_set_vpp(int on)
269 val = __raw_readl(VERSATILE_FLASHCTRL);
271 val |= VERSATILE_FLASHPROG_FLVPPEN;
273 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
274 __raw_writel(val, VERSATILE_FLASHCTRL);
277 static struct flash_platform_data versatile_flash_data = {
278 .map_name = "cfi_probe",
280 .init = versatile_flash_init,
281 .exit = versatile_flash_exit,
282 .set_vpp = versatile_flash_set_vpp,
285 static struct resource versatile_flash_resource = {
286 .start = VERSATILE_FLASH_BASE,
287 .end = VERSATILE_FLASH_BASE + VERSATILE_FLASH_SIZE,
288 .flags = IORESOURCE_MEM,
291 static struct platform_device versatile_flash_device = {
295 .platform_data = &versatile_flash_data,
298 .resource = &versatile_flash_resource,
301 static struct resource smc91x_resources[] = {
303 .start = VERSATILE_ETH_BASE,
304 .end = VERSATILE_ETH_BASE + SZ_64K - 1,
305 .flags = IORESOURCE_MEM,
310 .flags = IORESOURCE_IRQ,
314 static struct platform_device smc91x_device = {
317 .num_resources = ARRAY_SIZE(smc91x_resources),
318 .resource = smc91x_resources,
321 #define VERSATILE_SYSMCI (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_MCI_OFFSET)
323 unsigned int mmc_status(struct device *dev)
325 struct amba_device *adev = container_of(dev, struct amba_device, dev);
328 if (adev->res.start == VERSATILE_MMCI0_BASE)
333 return readl(VERSATILE_SYSMCI) & mask;
336 static struct mmc_platform_data mmc0_plat_data = {
337 .ocr_mask = MMC_VDD_32_33|MMC_VDD_33_34,
338 .status = mmc_status,
344 static const struct icst307_params versatile_oscvco_params = {
353 static void versatile_oscvco_set(struct clk *clk, struct icst307_vco vco)
355 void __iomem *sys_lock = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LOCK_OFFSET;
356 void __iomem *sys_osc = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_OSCCLCD_OFFSET;
359 val = readl(sys_osc) & ~0x7ffff;
360 val |= vco.v | (vco.r << 9) | (vco.s << 16);
362 writel(0xa05f, sys_lock);
363 writel(val, sys_osc);
367 static struct clk versatile_clcd_clk = {
369 .params = &versatile_oscvco_params,
370 .setvco = versatile_oscvco_set,
376 #define SYS_CLCD_MODE_MASK (3 << 0)
377 #define SYS_CLCD_MODE_888 (0 << 0)
378 #define SYS_CLCD_MODE_5551 (1 << 0)
379 #define SYS_CLCD_MODE_565_RLSB (2 << 0)
380 #define SYS_CLCD_MODE_565_BLSB (3 << 0)
381 #define SYS_CLCD_NLCDIOON (1 << 2)
382 #define SYS_CLCD_VDDPOSSWITCH (1 << 3)
383 #define SYS_CLCD_PWR3V5SWITCH (1 << 4)
384 #define SYS_CLCD_ID_MASK (0x1f << 8)
385 #define SYS_CLCD_ID_SANYO_3_8 (0x00 << 8)
386 #define SYS_CLCD_ID_UNKNOWN_8_4 (0x01 << 8)
387 #define SYS_CLCD_ID_EPSON_2_2 (0x02 << 8)
388 #define SYS_CLCD_ID_SANYO_2_5 (0x07 << 8)
389 #define SYS_CLCD_ID_VGA (0x1f << 8)
391 static struct clcd_panel vga = {
405 .vmode = FB_VMODE_NONINTERLACED,
409 .tim2 = TIM2_BCD | TIM2_IPC,
410 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
414 static struct clcd_panel sanyo_3_8_in = {
416 .name = "Sanyo QVGA",
428 .vmode = FB_VMODE_NONINTERLACED,
433 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
437 static struct clcd_panel sanyo_2_5_in = {
439 .name = "Sanyo QVGA Portrait",
450 .sync = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
451 .vmode = FB_VMODE_NONINTERLACED,
455 .tim2 = TIM2_IVS | TIM2_IHS | TIM2_IPC,
456 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
460 static struct clcd_panel epson_2_2_in = {
462 .name = "Epson QCIF",
474 .vmode = FB_VMODE_NONINTERLACED,
478 .tim2 = TIM2_BCD | TIM2_IPC,
479 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
484 * Detect which LCD panel is connected, and return the appropriate
485 * clcd_panel structure. Note: we do not have any information on
486 * the required timings for the 8.4in panel, so we presently assume
489 static struct clcd_panel *versatile_clcd_panel(void)
491 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
492 struct clcd_panel *panel = &vga;
495 val = readl(sys_clcd) & SYS_CLCD_ID_MASK;
496 if (val == SYS_CLCD_ID_SANYO_3_8)
497 panel = &sanyo_3_8_in;
498 else if (val == SYS_CLCD_ID_SANYO_2_5)
499 panel = &sanyo_2_5_in;
500 else if (val == SYS_CLCD_ID_EPSON_2_2)
501 panel = &epson_2_2_in;
502 else if (val == SYS_CLCD_ID_VGA)
505 printk(KERN_ERR "CLCD: unknown LCD panel ID 0x%08x, using VGA\n",
514 * Disable all display connectors on the interface module.
516 static void versatile_clcd_disable(struct clcd_fb *fb)
518 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
521 val = readl(sys_clcd);
522 val &= ~SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
523 writel(val, sys_clcd);
525 #ifdef CONFIG_MACH_VERSATILE_AB
527 * If the LCD is Sanyo 2x5 in on the IB2 board, turn the back-light off
529 if (machine_is_versatile_ab() && fb->panel == &sanyo_2_5_in) {
530 void __iomem *versatile_ib2_ctrl = __io_address(VERSATILE_IB2_CTRL);
533 ctrl = readl(versatile_ib2_ctrl);
535 writel(ctrl, versatile_ib2_ctrl);
541 * Enable the relevant connector on the interface module.
543 static void versatile_clcd_enable(struct clcd_fb *fb)
545 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
548 val = readl(sys_clcd);
549 val &= ~SYS_CLCD_MODE_MASK;
551 switch (fb->fb.var.green.length) {
553 val |= SYS_CLCD_MODE_5551;
556 val |= SYS_CLCD_MODE_565_RLSB;
559 val |= SYS_CLCD_MODE_888;
566 writel(val, sys_clcd);
569 * And now enable the PSUs
571 val |= SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
572 writel(val, sys_clcd);
574 #ifdef CONFIG_MACH_VERSATILE_AB
576 * If the LCD is Sanyo 2x5 in on the IB2 board, turn the back-light on
578 if (machine_is_versatile_ab() && fb->panel == &sanyo_2_5_in) {
579 void __iomem *versatile_ib2_ctrl = __io_address(VERSATILE_IB2_CTRL);
582 ctrl = readl(versatile_ib2_ctrl);
584 writel(ctrl, versatile_ib2_ctrl);
589 static unsigned long framesize = SZ_1M;
591 static int versatile_clcd_setup(struct clcd_fb *fb)
595 fb->panel = versatile_clcd_panel();
597 fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, framesize,
599 if (!fb->fb.screen_base) {
600 printk(KERN_ERR "CLCD: unable to map framebuffer\n");
604 fb->fb.fix.smem_start = dma;
605 fb->fb.fix.smem_len = framesize;
610 static int versatile_clcd_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
612 return dma_mmap_writecombine(&fb->dev->dev, vma,
614 fb->fb.fix.smem_start,
615 fb->fb.fix.smem_len);
618 static void versatile_clcd_remove(struct clcd_fb *fb)
620 dma_free_writecombine(&fb->dev->dev, fb->fb.fix.smem_len,
621 fb->fb.screen_base, fb->fb.fix.smem_start);
624 static struct clcd_board clcd_plat_data = {
626 .check = clcdfb_check,
627 .decode = clcdfb_decode,
628 .disable = versatile_clcd_disable,
629 .enable = versatile_clcd_enable,
630 .setup = versatile_clcd_setup,
631 .mmap = versatile_clcd_mmap,
632 .remove = versatile_clcd_remove,
635 #define AACI_IRQ { IRQ_AACI, NO_IRQ }
636 #define AACI_DMA { 0x80, 0x81 }
637 #define MMCI0_IRQ { IRQ_MMCI0A,IRQ_SIC_MMCI0B }
638 #define MMCI0_DMA { 0x84, 0 }
639 #define KMI0_IRQ { IRQ_SIC_KMI0, NO_IRQ }
640 #define KMI0_DMA { 0, 0 }
641 #define KMI1_IRQ { IRQ_SIC_KMI1, NO_IRQ }
642 #define KMI1_DMA { 0, 0 }
645 * These devices are connected directly to the multi-layer AHB switch
647 #define SMC_IRQ { NO_IRQ, NO_IRQ }
648 #define SMC_DMA { 0, 0 }
649 #define MPMC_IRQ { NO_IRQ, NO_IRQ }
650 #define MPMC_DMA { 0, 0 }
651 #define CLCD_IRQ { IRQ_CLCDINT, NO_IRQ }
652 #define CLCD_DMA { 0, 0 }
653 #define DMAC_IRQ { IRQ_DMAINT, NO_IRQ }
654 #define DMAC_DMA { 0, 0 }
657 * These devices are connected via the core APB bridge
659 #define SCTL_IRQ { NO_IRQ, NO_IRQ }
660 #define SCTL_DMA { 0, 0 }
661 #define WATCHDOG_IRQ { IRQ_WDOGINT, NO_IRQ }
662 #define WATCHDOG_DMA { 0, 0 }
663 #define GPIO0_IRQ { IRQ_GPIOINT0, NO_IRQ }
664 #define GPIO0_DMA { 0, 0 }
665 #define GPIO1_IRQ { IRQ_GPIOINT1, NO_IRQ }
666 #define GPIO1_DMA { 0, 0 }
667 #define RTC_IRQ { IRQ_RTCINT, NO_IRQ }
668 #define RTC_DMA { 0, 0 }
671 * These devices are connected via the DMA APB bridge
673 #define SCI_IRQ { IRQ_SCIINT, NO_IRQ }
674 #define SCI_DMA { 7, 6 }
675 #define UART0_IRQ { IRQ_UARTINT0, NO_IRQ }
676 #define UART0_DMA { 15, 14 }
677 #define UART1_IRQ { IRQ_UARTINT1, NO_IRQ }
678 #define UART1_DMA { 13, 12 }
679 #define UART2_IRQ { IRQ_UARTINT2, NO_IRQ }
680 #define UART2_DMA { 11, 10 }
681 #define SSP_IRQ { IRQ_SSPINT, NO_IRQ }
682 #define SSP_DMA { 9, 8 }
684 /* FPGA Primecells */
685 AMBA_DEVICE(aaci, "fpga:04", AACI, NULL);
686 AMBA_DEVICE(mmc0, "fpga:05", MMCI0, &mmc0_plat_data);
687 AMBA_DEVICE(kmi0, "fpga:06", KMI0, NULL);
688 AMBA_DEVICE(kmi1, "fpga:07", KMI1, NULL);
690 /* DevChip Primecells */
691 AMBA_DEVICE(smc, "dev:00", SMC, NULL);
692 AMBA_DEVICE(mpmc, "dev:10", MPMC, NULL);
693 AMBA_DEVICE(clcd, "dev:20", CLCD, &clcd_plat_data);
694 AMBA_DEVICE(dmac, "dev:30", DMAC, NULL);
695 AMBA_DEVICE(sctl, "dev:e0", SCTL, NULL);
696 AMBA_DEVICE(wdog, "dev:e1", WATCHDOG, NULL);
697 AMBA_DEVICE(gpio0, "dev:e4", GPIO0, NULL);
698 AMBA_DEVICE(gpio1, "dev:e5", GPIO1, NULL);
699 AMBA_DEVICE(rtc, "dev:e8", RTC, NULL);
700 AMBA_DEVICE(sci0, "dev:f0", SCI, NULL);
701 AMBA_DEVICE(uart0, "dev:f1", UART0, NULL);
702 AMBA_DEVICE(uart1, "dev:f2", UART1, NULL);
703 AMBA_DEVICE(uart2, "dev:f3", UART2, NULL);
704 AMBA_DEVICE(ssp0, "dev:f4", SSP, NULL);
706 static struct amba_device *amba_devs[] __initdata = {
728 #define VA_LEDS_BASE (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LED_OFFSET)
730 static void versatile_leds_event(led_event_t ledevt)
735 local_irq_save(flags);
736 val = readl(VA_LEDS_BASE);
740 val = val & ~VERSATILE_SYS_LED0;
744 val = val | VERSATILE_SYS_LED0;
748 val = val ^ VERSATILE_SYS_LED1;
759 writel(val, VA_LEDS_BASE);
760 local_irq_restore(flags);
762 #endif /* CONFIG_LEDS */
764 void __init versatile_init(void)
768 clk_register(&versatile_clcd_clk);
770 platform_device_register(&versatile_flash_device);
771 platform_device_register(&smc91x_device);
773 for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
774 struct amba_device *d = amba_devs[i];
775 amba_device_register(d, &iomem_resource);
779 leds_event = versatile_leds_event;
784 * Where is the timer (VA)?
786 #define TIMER0_VA_BASE __io_address(VERSATILE_TIMER0_1_BASE)
787 #define TIMER1_VA_BASE (__io_address(VERSATILE_TIMER0_1_BASE) + 0x20)
788 #define TIMER2_VA_BASE __io_address(VERSATILE_TIMER2_3_BASE)
789 #define TIMER3_VA_BASE (__io_address(VERSATILE_TIMER2_3_BASE) + 0x20)
790 #define VA_IC_BASE __io_address(VERSATILE_VIC_BASE)
793 * How long is the timer interval?
795 #define TIMER_INTERVAL (TICKS_PER_uSEC * mSEC_10)
796 #if TIMER_INTERVAL >= 0x100000
797 #define TIMER_RELOAD (TIMER_INTERVAL >> 8)
798 #define TIMER_DIVISOR (TIMER_CTRL_DIV256)
799 #define TICKS2USECS(x) (256 * (x) / TICKS_PER_uSEC)
800 #elif TIMER_INTERVAL >= 0x10000
801 #define TIMER_RELOAD (TIMER_INTERVAL >> 4) /* Divide by 16 */
802 #define TIMER_DIVISOR (TIMER_CTRL_DIV16)
803 #define TICKS2USECS(x) (16 * (x) / TICKS_PER_uSEC)
805 #define TIMER_RELOAD (TIMER_INTERVAL)
806 #define TIMER_DIVISOR (TIMER_CTRL_DIV1)
807 #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC)
811 * Returns number of ms since last clock interrupt. Note that interrupts
812 * will have been disabled by do_gettimeoffset()
814 static unsigned long versatile_gettimeoffset(void)
816 unsigned long ticks1, ticks2, status;
819 * Get the current number of ticks. Note that there is a race
820 * condition between us reading the timer and checking for
821 * an interrupt. We get around this by ensuring that the
822 * counter has not reloaded between our two reads.
824 ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
827 status = __raw_readl(VA_IC_BASE + VIC_RAW_STATUS);
828 ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
829 } while (ticks2 > ticks1);
832 * Number of ticks since last interrupt.
834 ticks1 = TIMER_RELOAD - ticks2;
837 * Interrupt pending? If so, we've reloaded once already.
839 * FIXME: Need to check this is effectively timer 0 that expires
841 if (status & IRQMASK_TIMERINT0_1)
842 ticks1 += TIMER_RELOAD;
845 * Convert the ticks to usecs
847 return TICKS2USECS(ticks1);
851 * IRQ handler for the timer
853 static irqreturn_t versatile_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
855 write_seqlock(&xtime_lock);
857 // ...clear the interrupt
858 writel(1, TIMER0_VA_BASE + TIMER_INTCLR);
862 write_sequnlock(&xtime_lock);
867 static struct irqaction versatile_timer_irq = {
868 .name = "Versatile Timer Tick",
869 .flags = IRQF_DISABLED | IRQF_TIMER,
870 .handler = versatile_timer_interrupt,
874 * Set up timer interrupt, and return the current time in seconds.
876 static void __init versatile_timer_init(void)
881 * set clock frequency:
882 * VERSATILE_REFCLK is 32KHz
883 * VERSATILE_TIMCLK is 1MHz
885 val = readl(__io_address(VERSATILE_SCTL_BASE));
886 writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
887 (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
888 (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
889 (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
890 __io_address(VERSATILE_SCTL_BASE));
893 * Initialise to a known state (all timers off)
895 writel(0, TIMER0_VA_BASE + TIMER_CTRL);
896 writel(0, TIMER1_VA_BASE + TIMER_CTRL);
897 writel(0, TIMER2_VA_BASE + TIMER_CTRL);
898 writel(0, TIMER3_VA_BASE + TIMER_CTRL);
900 writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_LOAD);
901 writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_VALUE);
902 writel(TIMER_DIVISOR | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC |
903 TIMER_CTRL_IE, TIMER0_VA_BASE + TIMER_CTRL);
906 * Make irqs happen for the system timer
908 setup_irq(IRQ_TIMERINT0_1, &versatile_timer_irq);
911 struct sys_timer versatile_timer = {
912 .init = versatile_timer_init,
913 .offset = versatile_gettimeoffset,