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/cnt32_to_63.h>
31 #include <asm/system.h>
32 #include <asm/hardware.h>
36 #include <asm/hardware/arm_timer.h>
37 #include <asm/hardware/icst307.h>
38 #include <asm/hardware/vic.h>
39 #include <asm/mach-types.h>
41 #include <asm/mach/arch.h>
42 #include <asm/mach/flash.h>
43 #include <asm/mach/irq.h>
44 #include <asm/mach/time.h>
45 #include <asm/mach/map.h>
46 #include <asm/mach/mmc.h>
52 * All IO addresses are mapped onto VA 0xFFFx.xxxx, where x.xxxx
55 * Setup a VA for the Versatile Vectored Interrupt Controller.
57 #define __io_address(n) __io(IO_ADDRESS(n))
58 #define VA_VIC_BASE __io_address(VERSATILE_VIC_BASE)
59 #define VA_SIC_BASE __io_address(VERSATILE_SIC_BASE)
61 static void sic_mask_irq(unsigned int irq)
64 writel(1 << irq, VA_SIC_BASE + SIC_IRQ_ENABLE_CLEAR);
67 static void sic_unmask_irq(unsigned int irq)
70 writel(1 << irq, VA_SIC_BASE + SIC_IRQ_ENABLE_SET);
73 static struct irq_chip sic_chip = {
77 .unmask = sic_unmask_irq,
81 sic_handle_irq(unsigned int irq, struct irq_desc *desc)
83 unsigned long status = readl(VA_SIC_BASE + SIC_IRQ_STATUS);
86 do_bad_IRQ(irq, desc);
91 irq = ffs(status) - 1;
92 status &= ~(1 << irq);
96 desc = irq_desc + irq;
97 desc_handle_irq(irq, desc);
102 #define IRQ_MMCI0A IRQ_VICSOURCE22
103 #define IRQ_AACI IRQ_VICSOURCE24
104 #define IRQ_ETH IRQ_VICSOURCE25
105 #define PIC_MASK 0xFFD00000
107 #define IRQ_MMCI0A IRQ_SIC_MMCI0A
108 #define IRQ_AACI IRQ_SIC_AACI
109 #define IRQ_ETH IRQ_SIC_ETH
113 void __init versatile_init_irq(void)
117 vic_init(VA_VIC_BASE, IRQ_VIC_START, ~0);
119 set_irq_chained_handler(IRQ_VICSOURCE31, sic_handle_irq);
121 /* Do second interrupt controller */
122 writel(~0, VA_SIC_BASE + SIC_IRQ_ENABLE_CLEAR);
124 for (i = IRQ_SIC_START; i <= IRQ_SIC_END; i++) {
125 if ((PIC_MASK & (1 << (i - IRQ_SIC_START))) == 0) {
126 set_irq_chip(i, &sic_chip);
127 set_irq_handler(i, handle_level_irq);
128 set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
133 * Interrupts on secondary controller from 0 to 8 are routed to
135 * Interrupts from 21 to 31 are routed directly to the VIC on
136 * the corresponding number on primary controller. This is controlled
137 * by setting PIC_ENABLEx.
139 writel(PIC_MASK, VA_SIC_BASE + SIC_INT_PIC_ENABLE);
142 static struct map_desc versatile_io_desc[] __initdata = {
144 .virtual = IO_ADDRESS(VERSATILE_SYS_BASE),
145 .pfn = __phys_to_pfn(VERSATILE_SYS_BASE),
149 .virtual = IO_ADDRESS(VERSATILE_SIC_BASE),
150 .pfn = __phys_to_pfn(VERSATILE_SIC_BASE),
154 .virtual = IO_ADDRESS(VERSATILE_VIC_BASE),
155 .pfn = __phys_to_pfn(VERSATILE_VIC_BASE),
159 .virtual = IO_ADDRESS(VERSATILE_SCTL_BASE),
160 .pfn = __phys_to_pfn(VERSATILE_SCTL_BASE),
164 #ifdef CONFIG_MACH_VERSATILE_AB
166 .virtual = IO_ADDRESS(VERSATILE_GPIO0_BASE),
167 .pfn = __phys_to_pfn(VERSATILE_GPIO0_BASE),
171 .virtual = IO_ADDRESS(VERSATILE_IB2_BASE),
172 .pfn = __phys_to_pfn(VERSATILE_IB2_BASE),
177 #ifdef CONFIG_DEBUG_LL
179 .virtual = IO_ADDRESS(VERSATILE_UART0_BASE),
180 .pfn = __phys_to_pfn(VERSATILE_UART0_BASE),
187 .virtual = IO_ADDRESS(VERSATILE_PCI_CORE_BASE),
188 .pfn = __phys_to_pfn(VERSATILE_PCI_CORE_BASE),
192 .virtual = (unsigned long)VERSATILE_PCI_VIRT_BASE,
193 .pfn = __phys_to_pfn(VERSATILE_PCI_BASE),
194 .length = VERSATILE_PCI_BASE_SIZE,
197 .virtual = (unsigned long)VERSATILE_PCI_CFG_VIRT_BASE,
198 .pfn = __phys_to_pfn(VERSATILE_PCI_CFG_BASE),
199 .length = VERSATILE_PCI_CFG_BASE_SIZE,
204 .virtual = VERSATILE_PCI_VIRT_MEM_BASE0,
205 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE0),
209 .virtual = VERSATILE_PCI_VIRT_MEM_BASE1,
210 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE1),
214 .virtual = VERSATILE_PCI_VIRT_MEM_BASE2,
215 .pfn = __phys_to_pfn(VERSATILE_PCI_MEM_BASE2),
223 void __init versatile_map_io(void)
225 iotable_init(versatile_io_desc, ARRAY_SIZE(versatile_io_desc));
228 #define VERSATILE_REFCOUNTER (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_24MHz_OFFSET)
231 * This is the Versatile sched_clock implementation. This has
232 * a resolution of 41.7ns, and a maximum value of about 35583 days.
234 * The return value is guaranteed to be monotonic in that range as
235 * long as there is always less than 89 seconds between successive
236 * calls to this function.
238 unsigned long long sched_clock(void)
240 unsigned long long v = cnt32_to_63(readl(VERSATILE_REFCOUNTER));
242 /* the <<1 gets rid of the cnt_32_to_63 top bit saving on a bic insn */
250 #define VERSATILE_FLASHCTRL (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_FLASH_OFFSET)
252 static int versatile_flash_init(void)
256 val = __raw_readl(VERSATILE_FLASHCTRL);
257 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
258 __raw_writel(val, VERSATILE_FLASHCTRL);
263 static void versatile_flash_exit(void)
267 val = __raw_readl(VERSATILE_FLASHCTRL);
268 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
269 __raw_writel(val, VERSATILE_FLASHCTRL);
272 static void versatile_flash_set_vpp(int on)
276 val = __raw_readl(VERSATILE_FLASHCTRL);
278 val |= VERSATILE_FLASHPROG_FLVPPEN;
280 val &= ~VERSATILE_FLASHPROG_FLVPPEN;
281 __raw_writel(val, VERSATILE_FLASHCTRL);
284 static struct flash_platform_data versatile_flash_data = {
285 .map_name = "cfi_probe",
287 .init = versatile_flash_init,
288 .exit = versatile_flash_exit,
289 .set_vpp = versatile_flash_set_vpp,
292 static struct resource versatile_flash_resource = {
293 .start = VERSATILE_FLASH_BASE,
294 .end = VERSATILE_FLASH_BASE + VERSATILE_FLASH_SIZE - 1,
295 .flags = IORESOURCE_MEM,
298 static struct platform_device versatile_flash_device = {
302 .platform_data = &versatile_flash_data,
305 .resource = &versatile_flash_resource,
308 static struct resource smc91x_resources[] = {
310 .start = VERSATILE_ETH_BASE,
311 .end = VERSATILE_ETH_BASE + SZ_64K - 1,
312 .flags = IORESOURCE_MEM,
317 .flags = IORESOURCE_IRQ,
321 static struct platform_device smc91x_device = {
324 .num_resources = ARRAY_SIZE(smc91x_resources),
325 .resource = smc91x_resources,
328 static struct resource versatile_i2c_resource = {
329 .start = VERSATILE_I2C_BASE,
330 .end = VERSATILE_I2C_BASE + SZ_4K - 1,
331 .flags = IORESOURCE_MEM,
334 static struct platform_device versatile_i2c_device = {
335 .name = "versatile-i2c",
338 .resource = &versatile_i2c_resource,
341 #define VERSATILE_SYSMCI (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_MCI_OFFSET)
343 unsigned int mmc_status(struct device *dev)
345 struct amba_device *adev = container_of(dev, struct amba_device, dev);
348 if (adev->res.start == VERSATILE_MMCI0_BASE)
353 return readl(VERSATILE_SYSMCI) & mask;
356 static struct mmc_platform_data mmc0_plat_data = {
357 .ocr_mask = MMC_VDD_32_33|MMC_VDD_33_34,
358 .status = mmc_status,
364 static const struct icst307_params versatile_oscvco_params = {
373 static void versatile_oscvco_set(struct clk *clk, struct icst307_vco vco)
375 void __iomem *sys_lock = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LOCK_OFFSET;
376 void __iomem *sys_osc = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_OSCCLCD_OFFSET;
379 val = readl(sys_osc) & ~0x7ffff;
380 val |= vco.v | (vco.r << 9) | (vco.s << 16);
382 writel(0xa05f, sys_lock);
383 writel(val, sys_osc);
387 static struct clk versatile_clcd_clk = {
389 .params = &versatile_oscvco_params,
390 .setvco = versatile_oscvco_set,
396 #define SYS_CLCD_MODE_MASK (3 << 0)
397 #define SYS_CLCD_MODE_888 (0 << 0)
398 #define SYS_CLCD_MODE_5551 (1 << 0)
399 #define SYS_CLCD_MODE_565_RLSB (2 << 0)
400 #define SYS_CLCD_MODE_565_BLSB (3 << 0)
401 #define SYS_CLCD_NLCDIOON (1 << 2)
402 #define SYS_CLCD_VDDPOSSWITCH (1 << 3)
403 #define SYS_CLCD_PWR3V5SWITCH (1 << 4)
404 #define SYS_CLCD_ID_MASK (0x1f << 8)
405 #define SYS_CLCD_ID_SANYO_3_8 (0x00 << 8)
406 #define SYS_CLCD_ID_UNKNOWN_8_4 (0x01 << 8)
407 #define SYS_CLCD_ID_EPSON_2_2 (0x02 << 8)
408 #define SYS_CLCD_ID_SANYO_2_5 (0x07 << 8)
409 #define SYS_CLCD_ID_VGA (0x1f << 8)
411 static struct clcd_panel vga = {
425 .vmode = FB_VMODE_NONINTERLACED,
429 .tim2 = TIM2_BCD | TIM2_IPC,
430 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
434 static struct clcd_panel sanyo_3_8_in = {
436 .name = "Sanyo QVGA",
448 .vmode = FB_VMODE_NONINTERLACED,
453 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
457 static struct clcd_panel sanyo_2_5_in = {
459 .name = "Sanyo QVGA Portrait",
470 .sync = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
471 .vmode = FB_VMODE_NONINTERLACED,
475 .tim2 = TIM2_IVS | TIM2_IHS | TIM2_IPC,
476 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
480 static struct clcd_panel epson_2_2_in = {
482 .name = "Epson QCIF",
494 .vmode = FB_VMODE_NONINTERLACED,
498 .tim2 = TIM2_BCD | TIM2_IPC,
499 .cntl = CNTL_LCDTFT | CNTL_LCDVCOMP(1),
504 * Detect which LCD panel is connected, and return the appropriate
505 * clcd_panel structure. Note: we do not have any information on
506 * the required timings for the 8.4in panel, so we presently assume
509 static struct clcd_panel *versatile_clcd_panel(void)
511 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
512 struct clcd_panel *panel = &vga;
515 val = readl(sys_clcd) & SYS_CLCD_ID_MASK;
516 if (val == SYS_CLCD_ID_SANYO_3_8)
517 panel = &sanyo_3_8_in;
518 else if (val == SYS_CLCD_ID_SANYO_2_5)
519 panel = &sanyo_2_5_in;
520 else if (val == SYS_CLCD_ID_EPSON_2_2)
521 panel = &epson_2_2_in;
522 else if (val == SYS_CLCD_ID_VGA)
525 printk(KERN_ERR "CLCD: unknown LCD panel ID 0x%08x, using VGA\n",
534 * Disable all display connectors on the interface module.
536 static void versatile_clcd_disable(struct clcd_fb *fb)
538 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
541 val = readl(sys_clcd);
542 val &= ~SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
543 writel(val, sys_clcd);
545 #ifdef CONFIG_MACH_VERSATILE_AB
547 * If the LCD is Sanyo 2x5 in on the IB2 board, turn the back-light off
549 if (machine_is_versatile_ab() && fb->panel == &sanyo_2_5_in) {
550 void __iomem *versatile_ib2_ctrl = __io_address(VERSATILE_IB2_CTRL);
553 ctrl = readl(versatile_ib2_ctrl);
555 writel(ctrl, versatile_ib2_ctrl);
561 * Enable the relevant connector on the interface module.
563 static void versatile_clcd_enable(struct clcd_fb *fb)
565 void __iomem *sys_clcd = __io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_CLCD_OFFSET;
568 val = readl(sys_clcd);
569 val &= ~SYS_CLCD_MODE_MASK;
571 switch (fb->fb.var.green.length) {
573 val |= SYS_CLCD_MODE_5551;
576 val |= SYS_CLCD_MODE_565_RLSB;
579 val |= SYS_CLCD_MODE_888;
586 writel(val, sys_clcd);
589 * And now enable the PSUs
591 val |= SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
592 writel(val, sys_clcd);
594 #ifdef CONFIG_MACH_VERSATILE_AB
596 * If the LCD is Sanyo 2x5 in on the IB2 board, turn the back-light on
598 if (machine_is_versatile_ab() && fb->panel == &sanyo_2_5_in) {
599 void __iomem *versatile_ib2_ctrl = __io_address(VERSATILE_IB2_CTRL);
602 ctrl = readl(versatile_ib2_ctrl);
604 writel(ctrl, versatile_ib2_ctrl);
609 static unsigned long framesize = SZ_1M;
611 static int versatile_clcd_setup(struct clcd_fb *fb)
615 fb->panel = versatile_clcd_panel();
617 fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, framesize,
619 if (!fb->fb.screen_base) {
620 printk(KERN_ERR "CLCD: unable to map framebuffer\n");
624 fb->fb.fix.smem_start = dma;
625 fb->fb.fix.smem_len = framesize;
630 static int versatile_clcd_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
632 return dma_mmap_writecombine(&fb->dev->dev, vma,
634 fb->fb.fix.smem_start,
635 fb->fb.fix.smem_len);
638 static void versatile_clcd_remove(struct clcd_fb *fb)
640 dma_free_writecombine(&fb->dev->dev, fb->fb.fix.smem_len,
641 fb->fb.screen_base, fb->fb.fix.smem_start);
644 static struct clcd_board clcd_plat_data = {
646 .check = clcdfb_check,
647 .decode = clcdfb_decode,
648 .disable = versatile_clcd_disable,
649 .enable = versatile_clcd_enable,
650 .setup = versatile_clcd_setup,
651 .mmap = versatile_clcd_mmap,
652 .remove = versatile_clcd_remove,
655 #define AACI_IRQ { IRQ_AACI, NO_IRQ }
656 #define AACI_DMA { 0x80, 0x81 }
657 #define MMCI0_IRQ { IRQ_MMCI0A,IRQ_SIC_MMCI0B }
658 #define MMCI0_DMA { 0x84, 0 }
659 #define KMI0_IRQ { IRQ_SIC_KMI0, NO_IRQ }
660 #define KMI0_DMA { 0, 0 }
661 #define KMI1_IRQ { IRQ_SIC_KMI1, NO_IRQ }
662 #define KMI1_DMA { 0, 0 }
665 * These devices are connected directly to the multi-layer AHB switch
667 #define SMC_IRQ { NO_IRQ, NO_IRQ }
668 #define SMC_DMA { 0, 0 }
669 #define MPMC_IRQ { NO_IRQ, NO_IRQ }
670 #define MPMC_DMA { 0, 0 }
671 #define CLCD_IRQ { IRQ_CLCDINT, NO_IRQ }
672 #define CLCD_DMA { 0, 0 }
673 #define DMAC_IRQ { IRQ_DMAINT, NO_IRQ }
674 #define DMAC_DMA { 0, 0 }
677 * These devices are connected via the core APB bridge
679 #define SCTL_IRQ { NO_IRQ, NO_IRQ }
680 #define SCTL_DMA { 0, 0 }
681 #define WATCHDOG_IRQ { IRQ_WDOGINT, NO_IRQ }
682 #define WATCHDOG_DMA { 0, 0 }
683 #define GPIO0_IRQ { IRQ_GPIOINT0, NO_IRQ }
684 #define GPIO0_DMA { 0, 0 }
685 #define GPIO1_IRQ { IRQ_GPIOINT1, NO_IRQ }
686 #define GPIO1_DMA { 0, 0 }
687 #define RTC_IRQ { IRQ_RTCINT, NO_IRQ }
688 #define RTC_DMA { 0, 0 }
691 * These devices are connected via the DMA APB bridge
693 #define SCI_IRQ { IRQ_SCIINT, NO_IRQ }
694 #define SCI_DMA { 7, 6 }
695 #define UART0_IRQ { IRQ_UARTINT0, NO_IRQ }
696 #define UART0_DMA { 15, 14 }
697 #define UART1_IRQ { IRQ_UARTINT1, NO_IRQ }
698 #define UART1_DMA { 13, 12 }
699 #define UART2_IRQ { IRQ_UARTINT2, NO_IRQ }
700 #define UART2_DMA { 11, 10 }
701 #define SSP_IRQ { IRQ_SSPINT, NO_IRQ }
702 #define SSP_DMA { 9, 8 }
704 /* FPGA Primecells */
705 AMBA_DEVICE(aaci, "fpga:04", AACI, NULL);
706 AMBA_DEVICE(mmc0, "fpga:05", MMCI0, &mmc0_plat_data);
707 AMBA_DEVICE(kmi0, "fpga:06", KMI0, NULL);
708 AMBA_DEVICE(kmi1, "fpga:07", KMI1, NULL);
710 /* DevChip Primecells */
711 AMBA_DEVICE(smc, "dev:00", SMC, NULL);
712 AMBA_DEVICE(mpmc, "dev:10", MPMC, NULL);
713 AMBA_DEVICE(clcd, "dev:20", CLCD, &clcd_plat_data);
714 AMBA_DEVICE(dmac, "dev:30", DMAC, NULL);
715 AMBA_DEVICE(sctl, "dev:e0", SCTL, NULL);
716 AMBA_DEVICE(wdog, "dev:e1", WATCHDOG, NULL);
717 AMBA_DEVICE(gpio0, "dev:e4", GPIO0, NULL);
718 AMBA_DEVICE(gpio1, "dev:e5", GPIO1, NULL);
719 AMBA_DEVICE(rtc, "dev:e8", RTC, NULL);
720 AMBA_DEVICE(sci0, "dev:f0", SCI, NULL);
721 AMBA_DEVICE(uart0, "dev:f1", UART0, NULL);
722 AMBA_DEVICE(uart1, "dev:f2", UART1, NULL);
723 AMBA_DEVICE(uart2, "dev:f3", UART2, NULL);
724 AMBA_DEVICE(ssp0, "dev:f4", SSP, NULL);
726 static struct amba_device *amba_devs[] __initdata = {
748 #define VA_LEDS_BASE (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LED_OFFSET)
750 static void versatile_leds_event(led_event_t ledevt)
755 local_irq_save(flags);
756 val = readl(VA_LEDS_BASE);
760 val = val & ~VERSATILE_SYS_LED0;
764 val = val | VERSATILE_SYS_LED0;
768 val = val ^ VERSATILE_SYS_LED1;
779 writel(val, VA_LEDS_BASE);
780 local_irq_restore(flags);
782 #endif /* CONFIG_LEDS */
784 void __init versatile_init(void)
788 clk_register(&versatile_clcd_clk);
790 platform_device_register(&versatile_flash_device);
791 platform_device_register(&versatile_i2c_device);
792 platform_device_register(&smc91x_device);
794 for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
795 struct amba_device *d = amba_devs[i];
796 amba_device_register(d, &iomem_resource);
800 leds_event = versatile_leds_event;
805 * Where is the timer (VA)?
807 #define TIMER0_VA_BASE __io_address(VERSATILE_TIMER0_1_BASE)
808 #define TIMER1_VA_BASE (__io_address(VERSATILE_TIMER0_1_BASE) + 0x20)
809 #define TIMER2_VA_BASE __io_address(VERSATILE_TIMER2_3_BASE)
810 #define TIMER3_VA_BASE (__io_address(VERSATILE_TIMER2_3_BASE) + 0x20)
811 #define VA_IC_BASE __io_address(VERSATILE_VIC_BASE)
814 * How long is the timer interval?
816 #define TIMER_INTERVAL (TICKS_PER_uSEC * mSEC_10)
817 #if TIMER_INTERVAL >= 0x100000
818 #define TIMER_RELOAD (TIMER_INTERVAL >> 8)
819 #define TIMER_DIVISOR (TIMER_CTRL_DIV256)
820 #define TICKS2USECS(x) (256 * (x) / TICKS_PER_uSEC)
821 #elif TIMER_INTERVAL >= 0x10000
822 #define TIMER_RELOAD (TIMER_INTERVAL >> 4) /* Divide by 16 */
823 #define TIMER_DIVISOR (TIMER_CTRL_DIV16)
824 #define TICKS2USECS(x) (16 * (x) / TICKS_PER_uSEC)
826 #define TIMER_RELOAD (TIMER_INTERVAL)
827 #define TIMER_DIVISOR (TIMER_CTRL_DIV1)
828 #define TICKS2USECS(x) ((x) / TICKS_PER_uSEC)
832 * Returns number of ms since last clock interrupt. Note that interrupts
833 * will have been disabled by do_gettimeoffset()
835 static unsigned long versatile_gettimeoffset(void)
837 unsigned long ticks1, ticks2, status;
840 * Get the current number of ticks. Note that there is a race
841 * condition between us reading the timer and checking for
842 * an interrupt. We get around this by ensuring that the
843 * counter has not reloaded between our two reads.
845 ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
848 status = __raw_readl(VA_IC_BASE + VIC_RAW_STATUS);
849 ticks2 = readl(TIMER0_VA_BASE + TIMER_VALUE) & 0xffff;
850 } while (ticks2 > ticks1);
853 * Number of ticks since last interrupt.
855 ticks1 = TIMER_RELOAD - ticks2;
858 * Interrupt pending? If so, we've reloaded once already.
860 * FIXME: Need to check this is effectively timer 0 that expires
862 if (status & IRQMASK_TIMERINT0_1)
863 ticks1 += TIMER_RELOAD;
866 * Convert the ticks to usecs
868 return TICKS2USECS(ticks1);
872 * IRQ handler for the timer
874 static irqreturn_t versatile_timer_interrupt(int irq, void *dev_id)
876 write_seqlock(&xtime_lock);
878 // ...clear the interrupt
879 writel(1, TIMER0_VA_BASE + TIMER_INTCLR);
883 write_sequnlock(&xtime_lock);
888 static struct irqaction versatile_timer_irq = {
889 .name = "Versatile Timer Tick",
890 .flags = IRQF_DISABLED | IRQF_TIMER,
891 .handler = versatile_timer_interrupt,
895 * Set up timer interrupt, and return the current time in seconds.
897 static void __init versatile_timer_init(void)
902 * set clock frequency:
903 * VERSATILE_REFCLK is 32KHz
904 * VERSATILE_TIMCLK is 1MHz
906 val = readl(__io_address(VERSATILE_SCTL_BASE));
907 writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
908 (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
909 (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
910 (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
911 __io_address(VERSATILE_SCTL_BASE));
914 * Initialise to a known state (all timers off)
916 writel(0, TIMER0_VA_BASE + TIMER_CTRL);
917 writel(0, TIMER1_VA_BASE + TIMER_CTRL);
918 writel(0, TIMER2_VA_BASE + TIMER_CTRL);
919 writel(0, TIMER3_VA_BASE + TIMER_CTRL);
921 writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_LOAD);
922 writel(TIMER_RELOAD, TIMER0_VA_BASE + TIMER_VALUE);
923 writel(TIMER_DIVISOR | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC |
924 TIMER_CTRL_IE, TIMER0_VA_BASE + TIMER_CTRL);
927 * Make irqs happen for the system timer
929 setup_irq(IRQ_TIMERINT0_1, &versatile_timer_irq);
932 struct sys_timer versatile_timer = {
933 .init = versatile_timer_init,
934 .offset = versatile_gettimeoffset,