Hi Jon and Mike, On Fri, 16 Sep 2011, Jon Hunter wrote:
> From: Mike Turquette <[email protected]> > > OMAP4 DPLL_ABE can enable a 4X multipler on top of the normal MN multipler > and divider. This is achieved by setting CM_CLKMODE_DPLL_ABE.DPLL_REGM4XEN > bit in CKGEN module of CM1. From the OMAP4 TRM: > > Fdpll = Fref x 2 x (4 x M/(N+1)) in case REGM4XEN bit field is set (only > applicable to DPLL_ABE). > > Add new round_rate() and recalc() functions for OMAP4, that check the > setting of REGM4XEN bit and handle this appropriately. The new functions > are a simple wrapper on top of the existing omap2_dpll_round_rate() and > omap2_dpll_get_rate() functions to handle the REGM4XEN bit. > > The REGM4XEN bit is only implemented for the ABE DPLL on OMAP4 and so > only dpll_abe_ck uses omap4_dpll_regm4xen_round_rate() and > omap4_dpll_regm4xen_recalc() functions. > > Signed-off-by: Mike Turquette <[email protected]> > Tested-by: Jon Hunter <[email protected]> Some changes have been made to this patch here, to fix a few minor bugs in error paths and to add documentation and Jon's Signed-off-by: (since he's in the submittal chain). Care to review and send any comments? Otherwise, I plan to queue this revised version for 3.2. Thanks for the great changelogs on this, and the other patches in this series. regards - Paul From: Mike Turquette <[email protected]> Date: Wed, 28 Sep 2011 00:00:31 -0600 Subject: [PATCH] ARM: OMAP4: clock: round_rate and recalc functions for DPLL_ABE OMAP4 DPLL_ABE can enable a 4X multipler on top of the normal MN multipler and divider. This is achieved by setting CM_CLKMODE_DPLL_ABE.DPLL_REGM4XEN bit in CKGEN module of CM1. From the OMAP4 TRM: Fdpll = Fref x 2 x (4 x M/(N+1)) in case REGM4XEN bit field is set (only applicable to DPLL_ABE). Add new round_rate() and recalc() functions for OMAP4, that check the setting of REGM4XEN bit and handle this appropriately. The new functions are a simple wrapper on top of the existing omap2_dpll_round_rate() and omap2_dpll_get_rate() functions to handle the REGM4XEN bit. The REGM4XEN bit is only implemented for the ABE DPLL on OMAP4 and so only dpll_abe_ck uses omap4_dpll_regm4xen_round_rate() and omap4_dpll_regm4xen_recalc() functions. Signed-off-by: Mike Turquette <[email protected]> Tested-by: Jon Hunter <[email protected]> Signed-off-by: Jon Hunter <[email protected]> [[email protected]: fixed attempt to return a negative from a fn returning unsigned; pass along errors from omap2_dpll_round_rate(); added documentation; added Jon's S-o-b] Signed-off-by: Paul Walmsley <[email protected]> --- arch/arm/mach-omap2/clock.h | 2 + arch/arm/mach-omap2/clock44xx.h | 7 +++ arch/arm/mach-omap2/clock44xx_data.c | 4 +- arch/arm/mach-omap2/dpll44xx.c | 69 ++++++++++++++++++++++++++++++++++ 4 files changed, 80 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h index 48ac568..2311bc2 100644 --- a/arch/arm/mach-omap2/clock.h +++ b/arch/arm/mach-omap2/clock.h @@ -66,6 +66,8 @@ void omap3_noncore_dpll_disable(struct clk *clk); int omap4_dpllmx_gatectrl_read(struct clk *clk); void omap4_dpllmx_allow_gatectrl(struct clk *clk); void omap4_dpllmx_deny_gatectrl(struct clk *clk); +long omap4_dpll_regm4xen_round_rate(struct clk *clk, unsigned long target_rate); +unsigned long omap4_dpll_regm4xen_recalc(struct clk *clk); #ifdef CONFIG_OMAP_RESET_CLOCKS void omap2_clk_disable_unused(struct clk *clk); diff --git a/arch/arm/mach-omap2/clock44xx.h b/arch/arm/mach-omap2/clock44xx.h index 7ceb870..287a46f 100644 --- a/arch/arm/mach-omap2/clock44xx.h +++ b/arch/arm/mach-omap2/clock44xx.h @@ -8,6 +8,13 @@ #ifndef __ARCH_ARM_MACH_OMAP2_CLOCK44XX_H #define __ARCH_ARM_MACH_OMAP2_CLOCK44XX_H +/* + * OMAP4430_REGM4XEN_MULT: If the CM_CLKMODE_DPLL_ABE.DPLL_REGM4XEN bit is + * set, then the DPLL's lock frequency is multiplied by 4 (OMAP4430 TRM + * vV Section 3.6.3.3.1 "DPLLs Output Clocks Parameters") + */ +#define OMAP4430_REGM4XEN_MULT 4 + int omap4xxx_clk_init(void); #endif diff --git a/arch/arm/mach-omap2/clock44xx_data.c b/arch/arm/mach-omap2/clock44xx_data.c index c0b6fbd..c98c0a2 100644 --- a/arch/arm/mach-omap2/clock44xx_data.c +++ b/arch/arm/mach-omap2/clock44xx_data.c @@ -270,8 +270,8 @@ static struct clk dpll_abe_ck = { .dpll_data = &dpll_abe_dd, .init = &omap2_init_dpll_parent, .ops = &clkops_omap3_noncore_dpll_ops, - .recalc = &omap3_dpll_recalc, - .round_rate = &omap2_dpll_round_rate, + .recalc = &omap4_dpll_regm4xen_recalc, + .round_rate = &omap4_dpll_regm4xen_round_rate, .set_rate = &omap3_noncore_dpll_set_rate, }; diff --git a/arch/arm/mach-omap2/dpll44xx.c b/arch/arm/mach-omap2/dpll44xx.c index 4e4da61..9c6a296 100644 --- a/arch/arm/mach-omap2/dpll44xx.c +++ b/arch/arm/mach-omap2/dpll44xx.c @@ -19,6 +19,7 @@ #include <plat/clock.h> #include "clock.h" +#include "clock44xx.h" #include "cm-regbits-44xx.h" /* Supported only on OMAP4 */ @@ -82,3 +83,71 @@ const struct clkops clkops_omap4_dpllmx_ops = { .deny_idle = omap4_dpllmx_deny_gatectrl, }; +/** + * omap4_dpll_regm4xen_recalc - compute DPLL rate, considering REGM4XEN bit + * @clk: struct clk * of the DPLL to compute the rate for + * + * Compute the output rate for the OMAP4 DPLL represented by @clk. + * Takes the REGM4XEN bit into consideration, which is needed for the + * OMAP4 ABE DPLL. Returns the DPLL's output rate (before M-dividers) + * upon success, or 0 upon error. + */ +unsigned long omap4_dpll_regm4xen_recalc(struct clk *clk) +{ + u32 v; + unsigned long rate; + struct dpll_data *dd; + + if (!clk || !clk->dpll_data) + return 0; + + dd = clk->dpll_data; + + rate = omap2_get_dpll_rate(clk); + + /* regm4xen adds a multiplier of 4 to DPLL calculations */ + v = __raw_readl(dd->control_reg); + if (v & OMAP4430_DPLL_REGM4XEN_MASK) + rate *= OMAP4430_REGM4XEN_MULT; + + return rate; +} + +/** + * omap4_dpll_regm4xen_round_rate - round DPLL rate, considering REGM4XEN bit + * @clk: struct clk * of the DPLL to round a rate for + * @target_rate: the desired rate of the DPLL + * + * Compute the rate that would be programmed into the DPLL hardware + * for @clk if set_rate() were to be provided with the rate + * @target_rate. Takes the REGM4XEN bit into consideration, which is + * needed for the OMAP4 ABE DPLL. Returns the rounded rate (before + * M-dividers) upon success, -EINVAL if @clk is null or not a DPLL, or + * ~0 if an error occurred in omap2_dpll_round_rate(). + */ +long omap4_dpll_regm4xen_round_rate(struct clk *clk, unsigned long target_rate) +{ + u32 v; + struct dpll_data *dd; + long r; + + if (!clk || !clk->dpll_data) + return -EINVAL; + + dd = clk->dpll_data; + + /* regm4xen adds a multiplier of 4 to DPLL calculations */ + v = __raw_readl(dd->control_reg) & OMAP4430_DPLL_REGM4XEN_MASK; + + if (v) + target_rate = target_rate / OMAP4430_REGM4XEN_MULT; + + r = omap2_dpll_round_rate(clk, target_rate); + if (r == ~0) + return r; + + if (v) + clk->dpll_data->last_rounded_rate *= OMAP4430_REGM4XEN_MULT; + + return clk->dpll_data->last_rounded_rate; +} -- 1.7.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
