From mboxrd@z Thu Jan 1 00:00:00 1970 From: zajec5@gmail.com (=?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?=) Date: Wed, 21 Jan 2015 09:44:26 +0100 Subject: [PATCH RFC] ARM: BCM5301X: add restart support Message-ID: <1421829866-9769-1-git-send-email-zajec5@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Signed-off-by: Rafa? Mi?ecki --- As you can see in the patch code, restarting BCM5301X devices requires performing some operation on its bcma bus. That of course requires getting a reference to it which I do by calling of_find_compatible_node with two NULLs. Unfortuantely this may not be preferred way to do that. I remember Arnd saying following thing when I was looking for chipcommon reference in another patch of mine: > This doesn't: you are now searching through all nodes starting at the > axi node rather than searching just through the children. Is there any better way to get reference to the bus node? --- arch/arm/mach-bcm/bcm_5301x.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/arch/arm/mach-bcm/bcm_5301x.c b/arch/arm/mach-bcm/bcm_5301x.c index e9bcbdb..5b8cd05 100644 --- a/arch/arm/mach-bcm/bcm_5301x.c +++ b/arch/arm/mach-bcm/bcm_5301x.c @@ -12,9 +12,26 @@ #include #include +#include static bool first_fault = true; +static struct bcma_bus *bcm5301x_get_bcma_bus(void) +{ + struct device_node *np; + struct platform_device *pdev; + + np = of_find_compatible_node(NULL, NULL, "brcm,bus-axi"); + if (!np) + return NULL; + + pdev = of_find_device_by_node(np); + if (!pdev) + return NULL; + + return platform_get_drvdata(pdev); +} + static int bcm5301x_abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { @@ -43,6 +60,19 @@ static void __init bcm5301x_init_early(void) "imprecise external abort"); } +static void bcm5301x_restart(enum reboot_mode mode, const char *cmd) +{ + struct bcma_bus *bus = bcm5301x_get_bcma_bus(); + + if (bus) + bcma_chipco_watchdog_timer_set(&bus->drv_cc, 1); + else + pr_warn("Unable to access bcma bus\n"); + + while (1) + ; +} + static const char __initconst *bcm5301x_dt_compat[] = { "brcm,bcm4708", NULL, @@ -52,5 +82,6 @@ DT_MACHINE_START(BCM5301X, "BCM5301X") .l2c_aux_val = 0, .l2c_aux_mask = ~0, .init_early = bcm5301x_init_early, + .restart = bcm5301x_restart, .dt_compat = bcm5301x_dt_compat, MACHINE_END -- 1.8.4.5