diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc/syslib/m8xx_wdt.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/ppc/syslib/m8xx_wdt.c')
-rw-r--r-- | arch/ppc/syslib/m8xx_wdt.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/ppc/syslib/m8xx_wdt.c b/arch/ppc/syslib/m8xx_wdt.c new file mode 100644 index 00000000000..7838a44bfd1 --- /dev/null +++ b/arch/ppc/syslib/m8xx_wdt.c @@ -0,0 +1,99 @@ +/* + * m8xx_wdt.c - MPC8xx watchdog driver + * + * Author: Florian Schirmer <jolt@tuxbox.org> + * + * 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <asm/8xx_immap.h> +#include <syslib/m8xx_wdt.h> + +static int wdt_timeout; + +void m8xx_wdt_reset(void) +{ + volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; + + imap->im_siu_conf.sc_swsr = 0x556c; /* write magic1 */ + imap->im_siu_conf.sc_swsr = 0xaa39; /* write magic2 */ +} + +static irqreturn_t m8xx_wdt_interrupt(int irq, void *dev, struct pt_regs *regs) +{ + volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; + + m8xx_wdt_reset(); + + imap->im_sit.sit_piscr |= PISCR_PS; /* clear irq */ + + return IRQ_HANDLED; +} + +void __init m8xx_wdt_handler_install(bd_t * binfo) +{ + volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR; + u32 pitc; + u32 sypcr; + u32 pitrtclk; + + sypcr = imap->im_siu_conf.sc_sypcr; + + if (!(sypcr & 0x04)) { + printk(KERN_NOTICE "m8xx_wdt: wdt disabled (SYPCR: 0x%08X)\n", + sypcr); + return; + } + + m8xx_wdt_reset(); + + printk(KERN_NOTICE + "m8xx_wdt: active wdt found (SWTC: 0x%04X, SWP: 0x%01X)\n", + (sypcr >> 16), sypcr & 0x01); + + wdt_timeout = (sypcr >> 16) & 0xFFFF; + + if (!wdt_timeout) + wdt_timeout = 0xFFFF; + + if (sypcr & 0x01) + wdt_timeout *= 2048; + + /* + * Fire trigger if half of the wdt ticked down + */ + + if (imap->im_sit.sit_rtcsc & RTCSC_38K) + pitrtclk = 9600; + else + pitrtclk = 8192; + + if ((wdt_timeout) > (UINT_MAX / pitrtclk)) + pitc = wdt_timeout / binfo->bi_intfreq * pitrtclk / 2; + else + pitc = pitrtclk * wdt_timeout / binfo->bi_intfreq / 2; + + imap->im_sit.sit_pitc = pitc << 16; + imap->im_sit.sit_piscr = + (mk_int_int_mask(PIT_INTERRUPT) << 8) | PISCR_PIE | PISCR_PTE; + + if (request_irq(PIT_INTERRUPT, m8xx_wdt_interrupt, 0, "watchdog", NULL)) + panic("m8xx_wdt: could not allocate watchdog irq!"); + + printk(KERN_NOTICE + "m8xx_wdt: keep-alive trigger installed (PITC: 0x%04X)\n", pitc); + + wdt_timeout /= binfo->bi_intfreq; +} + +int m8xx_wdt_get_timeout(void) +{ + return wdt_timeout; +} |