diff options
Diffstat (limited to 'arch/arm/mach-omap2/clock.c')
| -rw-r--r-- | arch/arm/mach-omap2/clock.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index 426d76f564e..d1f115d0eda 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -17,6 +17,8 @@ #include <linux/kernel.h> #include <linux/list.h> #include <linux/errno.h> +#include <linux/err.h> +#include <linux/delay.h> #include <linux/clk.h> #include <linux/io.h> #include <linux/bitops.h> @@ -349,6 +351,89 @@ void omap2_clk_disable_unused(struct clk *clk) } #endif +/** + * omap2_clk_switch_mpurate_at_boot - switch ARM MPU rate by boot-time argument + * @mpurate_ck_name: clk name of the clock to change rate + * + * Change the ARM MPU clock rate to the rate specified on the command + * line, if one was specified. @mpurate_ck_name should be + * "virt_prcm_set" on OMAP2xxx and "dpll1_ck" on OMAP34xx/OMAP36xx. + * XXX Does not handle voltage scaling - on OMAP2xxx this is currently + * handled by the virt_prcm_set clock, but this should be handled by + * the OPP layer. XXX This is intended to be handled by the OPP layer + * code in the near future and should be removed from the clock code. + * Returns -EINVAL if 'mpurate' is zero or if clk_set_rate() rejects + * the rate, -ENOENT if the struct clk referred to by @mpurate_ck_name + * cannot be found, or 0 upon success. + */ +int __init omap2_clk_switch_mpurate_at_boot(const char *mpurate_ck_name) +{ + struct clk *mpurate_ck; + int r; + + if (!mpurate) + return -EINVAL; + + mpurate_ck = clk_get(NULL, mpurate_ck_name); + if (WARN(IS_ERR(mpurate_ck), "Failed to get %s.\n", mpurate_ck_name)) + return -ENOENT; + + r = clk_set_rate(mpurate_ck, mpurate); + if (IS_ERR_VALUE(r)) { + WARN(1, "clock: %s: unable to set MPU rate to %d: %d\n", + mpurate_ck->name, mpurate, r); + return -EINVAL; + } + + calibrate_delay(); + recalculate_root_clocks(); + + clk_put(mpurate_ck); + + return 0; +} + +/** + * omap2_clk_print_new_rates - print summary of current clock tree rates + * @hfclkin_ck_name: clk name for the off-chip HF oscillator + * @core_ck_name: clk name for the on-chip CORE_CLK + * @mpu_ck_name: clk name for the ARM MPU clock + * + * Prints a short message to the console with the HFCLKIN oscillator + * rate, the rate of the CORE clock, and the rate of the ARM MPU clock. + * Called by the boot-time MPU rate switching code. XXX This is intended + * to be handled by the OPP layer code in the near future and should be + * removed from the clock code. No return value. + */ +void __init omap2_clk_print_new_rates(const char *hfclkin_ck_name, + const char *core_ck_name, + const char *mpu_ck_name) +{ + struct clk *hfclkin_ck, *core_ck, *mpu_ck; + unsigned long hfclkin_rate; + + mpu_ck = clk_get(NULL, mpu_ck_name); + if (WARN(IS_ERR(mpu_ck), "clock: failed to get %s.\n", mpu_ck_name)) + return; + + core_ck = clk_get(NULL, core_ck_name); + if (WARN(IS_ERR(core_ck), "clock: failed to get %s.\n", core_ck_name)) + return; + + hfclkin_ck = clk_get(NULL, hfclkin_ck_name); + if (WARN(IS_ERR(hfclkin_ck), "Failed to get %s.\n", hfclkin_ck_name)) + return; + + hfclkin_rate = clk_get_rate(hfclkin_ck); + + pr_info("Switched to new clocking rate (Crystal/Core/MPU): " + "%ld.%01ld/%ld/%ld MHz\n", + (hfclkin_rate / 1000000), + ((hfclkin_rate / 100000) % 10), + (clk_get_rate(core_ck) / 1000000), + (clk_get_rate(mpu_ck) / 1000000)); +} + /* Common data */ struct clk_functions omap2_clk_functions = { |