From f49f4ab95c301dbccad0efe85296d908b8ae7ad4 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Mon, 29 Oct 2012 14:40:18 +0100 Subject: [PATCH] x86/ce4100: Fix pm_poweroff The CE4100 platform is currently missing a proper pm_poweroff implementation leading to poweroff making the CPU spin forever and the CE4100 platform does not enter a low-power mode where the external Power Management Unit can properly power off the system. Power off on this platform is implemented pretty much like reboot, by writing to the SoC built-in 8051 microcontroller mapped at I/O port 0xcf9, the value 0x4. Signed-off-by: Florian Fainelli Acked-by: Sebastian Andrzej Siewior Cc: rui.zhang@intel.com Cc: alan@linux.intel.com Link: http://lkml.kernel.org/r/1351518020-25556-2-git-send-email-ffainelli@freebox.fr Signed-off-by: Ingo Molnar --- arch/x86/platform/ce4100/ce4100.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/arch/x86/platform/ce4100/ce4100.c b/arch/x86/platform/ce4100/ce4100.c index 4c61b52191eb..5de16e359fe6 100644 --- a/arch/x86/platform/ce4100/ce4100.c +++ b/arch/x86/platform/ce4100/ce4100.c @@ -27,6 +27,18 @@ static int ce4100_i8042_detect(void) return 0; } +/* + * The CE4100 platform has an internal 8051 Microcontroller which is + * responsible for signaling to the external Power Management Unit the + * intention to reset, reboot or power off the system. This 8051 device has + * its command register mapped at I/O port 0xcf9 and the value 0x4 is used + * to power off the system. + */ +static void ce4100_power_off(void) +{ + outb(0x4, 0xcf9); +} + #ifdef CONFIG_SERIAL_8250 static unsigned int mem_serial_in(struct uart_port *p, int offset) @@ -143,4 +155,6 @@ void __init x86_ce4100_early_setup(void) x86_init.pci.init_irq = sdv_pci_init; x86_init.mpparse.setup_ioapic_ids = setup_ioapic_ids_from_mpc_nocheck; #endif + + pm_power_off = ce4100_power_off; }