From 2f334a3896714b47e24cc4cd08eed11d1a7f0d8e Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Mon, 29 Oct 2012 20:56:07 -0600 Subject: ARM: OMAP2+: PRCM: create SoC-specific chip restart functions Split omap_prcm_restart() from mach-omap2/prcm.c into SoC-specific variants. These functions need to be able to save the reboot reason into the scratchpad RAM. This implies a dependency on both the PRM and SCM IP blocks, so they've been moved into their own file. This will eventually call functions in the PRM and SCM drivers, once those are created. Vaibhav Hiremath identified an unused prototype in the first version of this patch - now removed. Tony Lindgren noted a compile problem with some RMK Kconfigs; resolved in this patch. Signed-off-by: Paul Walmsley Cc: Vaibhav Hiremath Tested-by: Vaibhav Hiremath Cc: Tony Lindgren --- arch/arm/mach-omap2/omap2-restart.c | 65 +++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 arch/arm/mach-omap2/omap2-restart.c (limited to 'arch/arm/mach-omap2/omap2-restart.c') diff --git a/arch/arm/mach-omap2/omap2-restart.c b/arch/arm/mach-omap2/omap2-restart.c new file mode 100644 index 000000000000..be6bc89ab1e8 --- /dev/null +++ b/arch/arm/mach-omap2/omap2-restart.c @@ -0,0 +1,65 @@ +/* + * omap2-restart.c - code common to all OMAP2xxx machines. + * + * Copyright (C) 2012 Texas Instruments + * Paul Walmsley + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include +#include +#include + +#include "common.h" +#include "prm2xxx.h" + +/* + * reset_virt_prcm_set_ck, reset_sys_ck: pointers to the virt_prcm_set + * clock and the sys_ck. Used during the reset process + */ +static struct clk *reset_virt_prcm_set_ck, *reset_sys_ck; + +/* Reboot handling */ + +/** + * omap2xxx_restart - Set DPLL to bypass mode for reboot to work + * + * Set the DPLL to bypass so that reboot completes successfully. No + * return value. + */ +void omap2xxx_restart(char mode, const char *cmd) +{ + u32 rate; + + rate = clk_get_rate(reset_sys_ck); + clk_set_rate(reset_virt_prcm_set_ck, rate); + + /* XXX Should save the cmd argument for use after the reboot */ + + omap2xxx_prm_dpll_reset(); /* never returns */ + while (1); +} + +/** + * omap2xxx_common_look_up_clks_for_reset - look up clocks needed for restart + * + * Some clocks need to be looked up in advance for the SoC restart + * operation to work - see omap2xxx_restart(). Returns -EINVAL upon + * error or 0 upon success. + */ +static int __init omap2xxx_common_look_up_clks_for_reset(void) +{ + reset_virt_prcm_set_ck = clk_get(NULL, "virt_prcm_set"); + if (IS_ERR(reset_virt_prcm_set_ck)) + return -EINVAL; + + reset_sys_ck = clk_get(NULL, "sys_ck"); + if (IS_ERR(reset_sys_ck)) + return -EINVAL; + + return 0; +} +core_initcall(omap2xxx_common_look_up_clks_for_reset); -- cgit