Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757410AbZA1Uew (ORCPT ); Wed, 28 Jan 2009 15:34:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755382AbZA1U30 (ORCPT ); Wed, 28 Jan 2009 15:29:26 -0500 Received: from utopia.booyaka.com ([72.9.107.138]:32891 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754037AbZA1U3W (ORCPT ); Wed, 28 Jan 2009 15:29:22 -0500 MBOX-Line: From nobody Wed Jan 28 12:27:42 2009 From: Paul Walmsley Subject: [PATCH E 05/14] OMAP3 clock: add omap3_core_dpll_m2_set_rate() To: linux-arm-kernel@lists.arm.linux.org.uk, linux-kernel@vger.kernel.org Cc: linux-omap@vger.kernel.org, Paul Walmsley , Tony Lindgren Date: Wed, 28 Jan 2009 12:27:42 -0700 Message-ID: <20090128192739.29333.84278.stgit@localhost.localdomain> In-Reply-To: <20090128192551.29333.82943.stgit@localhost.localdomain> References: <20090128192551.29333.82943.stgit@localhost.localdomain> User-Agent: StGIT/0.14.3.222.gddca MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4391 Lines: 137 Add the omap3_core_dpll_m2_set_rate() function to the OMAP3 clock code, which calls into the SRAM function omap3_sram_configure_core_dpll() to change the CORE DPLL M2 divider. (SRAM code is necessary since rate changes on clocks upstream from the SDRC can glitch SDRAM accesses.) Use this function for the set_rate function pointer in the dpll3_m2_ck struct clk. With this function in place, PM/OPP code should be able to alter SDRAM speed via code similar to: clk_set_rate(&dpll3_m2_ck, target_rate). linux-omap source commit is 7f8b2b0f4fe52238c67d79dedcd2794dcef4dddd. Signed-off-by: Paul Walmsley Signed-off-by: Tony Lindgren --- arch/arm/mach-omap2/clock34xx.c | 65 +++++++++++++++++++++++++++++++++++++++ arch/arm/mach-omap2/clock34xx.h | 9 ++--- 2 files changed, 69 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index 3dba9ca..2c655be 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -434,6 +434,71 @@ static int omap3_noncore_dpll_set_rate(struct clk *clk, unsigned long rate) return 0; } + +/* + * CORE DPLL (DPLL3) rate programming functions + * + * These call into SRAM code to do the actual CM writes, since the SDRAM + * is clocked from DPLL3. + */ + +/** + * omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider + * @clk: struct clk * of DPLL to set + * @rate: rounded target rate + * + * Program the DPLL M2 divider with the rounded target rate. Returns + * -EINVAL upon error, or 0 upon success. + */ +static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) +{ + u32 new_div = 0; + unsigned long validrate, sdrcrate; + struct omap_sdrc_params *sp; + + if (!clk || !rate) + return -EINVAL; + + if (clk != &dpll3_m2_ck) + return -EINVAL; + + if (rate == clk->rate) + return 0; + + validrate = omap2_clksel_round_rate_div(clk, rate, &new_div); + if (validrate != rate) + return -EINVAL; + + sdrcrate = sdrc_ick.rate; + if (rate > clk->rate) + sdrcrate <<= ((rate / clk->rate) - 1); + else + sdrcrate >>= ((clk->rate / rate) - 1); + + sp = omap2_sdrc_get_params(sdrcrate); + if (!sp) + return -EINVAL; + + pr_info("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate, + validrate); + pr_info("clock: SDRC timing params used: %08x %08x %08x\n", + sp->rfr_ctrl, sp->actim_ctrla, sp->actim_ctrlb); + + /* REVISIT: SRAM code doesn't support other M2 divisors yet */ + WARN_ON(new_div != 1 && new_div != 2); + + /* REVISIT: Add SDRC_MR changing to this code also */ + local_irq_disable(); + omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla, + sp->actim_ctrlb, new_div); + local_irq_enable(); + + omap2_clksel_recalc(clk); + + return 0; +} + + /* DPLL autoidle read/set code */ diff --git a/arch/arm/mach-omap2/clock34xx.h b/arch/arm/mach-omap2/clock34xx.h index 70a1532..5357507 100644 --- a/arch/arm/mach-omap2/clock34xx.h +++ b/arch/arm/mach-omap2/clock34xx.h @@ -35,6 +35,7 @@ static u32 omap3_dpll_autoidle_read(struct clk *clk); static int omap3_noncore_dpll_enable(struct clk *clk); static void omap3_noncore_dpll_disable(struct clk *clk); static int omap3_noncore_dpll_set_rate(struct clk *clk, unsigned long rate); +static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate); /* Maximum DPLL multiplier, divider values for OMAP3 */ #define OMAP3_MAX_DPLL_MULT 2048 @@ -499,11 +500,7 @@ static const struct clksel div31_dpll3m2_clksel[] = { { .parent = NULL } }; -/* - * DPLL3 output M2 - * REVISIT: This DPLL output divider must be changed in SRAM, so until - * that code is ready, this should remain a 'read-only' clksel clock. - */ +/* DPLL3 output M2 - primary control point for CORE speed */ static struct clk dpll3_m2_ck = { .name = "dpll3_m2_ck", .parent = &dpll3_ck, @@ -515,6 +512,8 @@ static struct clk dpll3_m2_ck = { .flags = CLOCK_IN_OMAP343X | RATE_PROPAGATES | PARENT_CONTROLS_CLOCK, .clkdm = { .name = "dpll3_clkdm" }, + .round_rate = &omap2_clksel_round_rate, + .set_rate = &omap3_core_dpll_m2_set_rate, .recalc = &omap2_clksel_recalc, }; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/