From 6adb8f388ef2f23d4a81e1e42d15f22d62749a06 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:24 -0600 Subject: OMAP3 clock: remove wait for DPLL3 M2 clock to stabilize The original CDP kernel that this code comes from waited for 0x800 loops after switching the CORE DPLL M2 divider. This does not appear to be necessary. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/sram34xx.S | 3 --- 1 file changed, 3 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index c080c82521e..84781a6cd26 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -102,9 +102,6 @@ configure_core_dpll: orr r12, r12, r3, lsl #0x1B @ r3 contains the M2 val str r12, [r11] ldr r12, [r11] @ posted-write barrier for CM - mov r12, #0x800 @ wait for the clock to stabilise - cmp r3, #2 - bne wait_clk_stable bx lr wait_clk_stable: subs r12, r12, #1 -- cgit v1.2.3 From 2f135eaf182761bb9a5cbd5138a447b0ad2a1fef Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:25 -0600 Subject: OMAP3 clock: initialize SDRC timings at kernel start On the OMAP3, initialize SDRC timings when the kernel boots. This ensures that the kernel is running with known, optimized SDRC timings, rather than whatever was configured by the bootloader. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/clock34xx.c | 3 --- arch/arm/mach-omap2/io.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+), 3 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index 9e43fe5209d..5458ab3bf65 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -718,9 +718,6 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) 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; diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c index 32afd944821..3a86b0f6603 100644 --- a/arch/arm/mach-omap2/io.c +++ b/arch/arm/mach-omap2/io.c @@ -21,6 +21,7 @@ #include #include #include +#include #include @@ -241,6 +242,40 @@ void __init omap2_map_common_io(void) omapfb_reserve_sdram(); } +/* + * omap2_init_reprogram_sdrc - reprogram SDRC timing parameters + * + * Sets the CORE DPLL3 M2 divider to the same value that it's at + * currently. This has the effect of setting the SDRC SDRAM AC timing + * registers to the values currently defined by the kernel. Currently + * only defined for OMAP3; will return 0 if called on OMAP2. Returns + * -EINVAL if the dpll3_m2_ck cannot be found, 0 if called on OMAP2, + * or passes along the return value of clk_set_rate(). + */ +static int __init _omap2_init_reprogram_sdrc(void) +{ + struct clk *dpll3_m2_ck; + int v = -EINVAL; + long rate; + + if (!cpu_is_omap34xx()) + return 0; + + dpll3_m2_ck = clk_get(NULL, "dpll3_m2_ck"); + if (!dpll3_m2_ck) + return -EINVAL; + + rate = clk_get_rate(dpll3_m2_ck); + pr_info("Reprogramming SDRC clock to %ld Hz\n", rate); + v = clk_set_rate(dpll3_m2_ck, rate); + if (v) + pr_err("dpll3_m2_clk rate change failed: %d\n", v); + + clk_put(dpll3_m2_ck); + + return v; +} + void __init omap2_init_common_hw(struct omap_sdrc_params *sp) { omap2_mux_init(); @@ -249,6 +284,7 @@ void __init omap2_init_common_hw(struct omap_sdrc_params *sp) clkdm_init(clockdomains_omap, clkdm_pwrdm_autodeps); omap2_clk_init(); omap2_sdrc_init(sp); + _omap2_init_reprogram_sdrc(); #endif gpmc_init(); } -- cgit v1.2.3 From c9812d042a21eb492a36cfabf9f41107f5ecee3d Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:26 -0600 Subject: OMAP3 clock: add a short delay when lowering CORE clk rate When changing the SDRAM clock from 166MHz to 83MHz via the CORE DPLL M2 divider, add a short delay before returning to SDRAM to allow the SDRC time to stabilize. Without this delay, the system is prone to random panics upon re-entering SDRAM. This time delay varies based on MPU frequency. At 500MHz MPU frequency at room temperature, 64 loops seems to work okay; so add another 32 loops for environmental and process variation. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/clock34xx.c | 30 ++++++++++++++++++++++++++++-- arch/arm/mach-omap2/sram34xx.S | 20 +++++++++----------- 2 files changed, 37 insertions(+), 13 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index 5458ab3bf65..4bfa650bb34 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -286,6 +286,20 @@ static struct omap_clk omap34xx_clks[] = { #define MIN_SDRC_DLL_LOCK_FREQ 83000000 +#define CYCLES_PER_MHZ 1000000 + +/* Scale factor for fixed-point arith in omap3_core_dpll_m2_set_rate() */ +#define SDRC_MPURATE_SCALE 8 + +/* 2^SDRC_MPURATE_BASE_SHIFT: MPU MHz that SDRC_MPURATE_LOOPS is defined for */ +#define SDRC_MPURATE_BASE_SHIFT 9 + +/* + * SDRC_MPURATE_LOOPS: Number of MPU loops to execute at + * 2^MPURATE_BASE_SHIFT MHz for SDRC to stabilize + */ +#define SDRC_MPURATE_LOOPS 96 + /** * omap3_dpll_recalc - recalculate DPLL rate * @clk: DPLL struct clk @@ -709,7 +723,8 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) { u32 new_div = 0; u32 unlock_dll = 0; - unsigned long validrate, sdrcrate; + u32 c; + unsigned long validrate, sdrcrate, mpurate; struct omap_sdrc_params *sp; if (!clk || !rate) @@ -737,6 +752,17 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) unlock_dll = 1; } + /* + * XXX This only needs to be done when the CPU frequency changes + */ + mpurate = arm_fck.rate / CYCLES_PER_MHZ; + c = (mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT; + c += 1; /* for safety */ + c *= SDRC_MPURATE_LOOPS; + c >>= SDRC_MPURATE_SCALE; + if (c == 0) + c = 1; + pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate, validrate); pr_debug("clock: SDRC timing params used: %08x %08x %08x\n", @@ -747,7 +773,7 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) /* REVISIT: Add SDRC_MR changing to this code also */ omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla, - sp->actim_ctrlb, new_div, unlock_dll); + sp->actim_ctrlb, new_div, unlock_dll, c); return 0; } diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 84781a6cd26..8d4a88c3071 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -42,10 +42,14 @@ * r0 = sdrc_rfr_ctrl r1 = sdrc_actim_ctrla r2 = sdrc_actim_ctrlb r3 = M2 * r4 = Unlock SDRC DLL? (1 = yes, 0 = no) -- only unlock DLL for * SDRC rates < 83MHz + * r5 = number of MPU cycles to wait for SDRC to stabilize after + * reprogramming the SDRC when switching to a slower MPU speed + * */ ENTRY(omap3_sram_configure_core_dpll) stmfd sp!, {r1-r12, lr} @ store regs to stack ldr r4, [sp, #52] @ pull extra args off the stack + ldr r5, [sp, #56] @ load extra args from the stack dsb @ flush buffered writes to interconnect cmp r3, #0x2 blne configure_sdrc @@ -59,7 +63,11 @@ ENTRY(omap3_sram_configure_core_dpll) bleq wait_dll_unlock blne wait_dll_lock cmp r3, #0x1 - blne configure_sdrc + beq return_to_sdram + bl configure_sdrc + mov r12, r5 @ if slowing, wait for SDRC to stabilize + bl wait_clk_stable +return_to_sdram: isb @ prevent speculative exec past here mov r0, #0 @ return value ldmfd sp!, {r1-r12, pc} @ restore regs and return @@ -106,16 +114,6 @@ configure_core_dpll: wait_clk_stable: subs r12, r12, #1 bne wait_clk_stable - nop - nop - nop - nop - nop - nop - nop - nop - nop - nop bx lr enable_sdrc: ldr r11, omap3_cm_iclken1_core -- cgit v1.2.3 From d0ba3922ae241a87d22a1c3ffad72b96fe993c9a Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:27 -0600 Subject: OMAP3 clock/SDRC: program SDRC_MR register during SDRC clock change Program the SDRC_MR_0 register as well during SDRC clock changes. This register allows selection of the memory CAS latency. Some SDRAM chips, such as the Qimonda HYB18M512160AF6, have a lower CAS latency at lower clock rates. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/clock34xx.c | 4 ++-- arch/arm/mach-omap2/sram34xx.S | 8 +++++++- 2 files changed, 9 insertions(+), 3 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index 4bfa650bb34..cf41ab55fa9 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -771,9 +771,9 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) /* 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 */ omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla, - sp->actim_ctrlb, new_div, unlock_dll, c); + sp->actim_ctrlb, new_div, unlock_dll, c, + sp->mr); return 0; } diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 8d4a88c3071..d13f1cc4bd5 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -44,12 +44,14 @@ * SDRC rates < 83MHz * r5 = number of MPU cycles to wait for SDRC to stabilize after * reprogramming the SDRC when switching to a slower MPU speed + * r6 = SDRC_MR_0 register value * */ ENTRY(omap3_sram_configure_core_dpll) stmfd sp!, {r1-r12, lr} @ store regs to stack ldr r4, [sp, #52] @ pull extra args off the stack ldr r5, [sp, #56] @ load extra args from the stack + ldr r6, [sp, #60] @ load extra args from the stack dsb @ flush buffered writes to interconnect cmp r3, #0x2 blne configure_sdrc @@ -151,7 +153,9 @@ configure_sdrc: str r1, [r11] ldr r11, omap3_sdrc_actim_ctrlb str r2, [r11] - ldr r2, [r11] @ posted-write barrier for SDRC + ldr r11, omap3_sdrc_mr_0 + str r6, [r11] + ldr r6, [r11] @ posted-write barrier for SDRC bx lr omap3_sdrc_power: @@ -168,6 +172,8 @@ omap3_sdrc_actim_ctrla: .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_A_0) omap3_sdrc_actim_ctrlb: .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_B_0) +omap3_sdrc_mr_0: + .word OMAP34XX_SDRC_REGADDR(SDRC_MR_0) omap3_sdrc_dlla_status: .word OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS) omap3_sdrc_dlla_ctrl: -- cgit v1.2.3 From 4267b5d15269ea6b26736a2ccd4c213e63e547ab Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:27 -0600 Subject: OMAP3 SRAM: add more comments on the SRAM code Clean up comments and copyrights on the CORE DPLL3 M2 divider change code. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/sram34xx.S | 45 ++++++++++++++++++++++-------------------- 1 file changed, 24 insertions(+), 21 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index d13f1cc4bd5..37a1e1fc0ab 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -3,13 +3,12 @@ * * Omap3 specific functions that need to be run in internal SRAM * - * (C) Copyright 2007 - * Texas Instruments Inc. - * Rajendra Nayak + * Copyright (C) 2004, 2007, 2008 Texas Instruments, Inc. + * Copyright (C) 2008 Nokia Corporation * - * (C) Copyright 2004 - * Texas Instruments, + * Rajendra Nayak * Richard Woodruff + * Paul Walmsley * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as @@ -38,13 +37,16 @@ .text /* - * Change frequency of core dpll - * r0 = sdrc_rfr_ctrl r1 = sdrc_actim_ctrla r2 = sdrc_actim_ctrlb r3 = M2 - * r4 = Unlock SDRC DLL? (1 = yes, 0 = no) -- only unlock DLL for + * omap3_sram_configure_core_dpll - change DPLL3 M2 divider + * r0 = new SDRC_RFR_CTRL register contents + * r1 = new SDRC_ACTIM_CTRLA register contents + * r2 = new SDRC_ACTIM_CTRLB register contents + * r3 = new M2 divider setting (only 1 and 2 supported right now) + * r4 = unlock SDRC DLL? (1 = yes, 0 = no). Only unlock DLL for * SDRC rates < 83MHz * r5 = number of MPU cycles to wait for SDRC to stabilize after * reprogramming the SDRC when switching to a slower MPU speed - * r6 = SDRC_MR_0 register value + * r6 = new SDRC_MR_0 register value * */ ENTRY(omap3_sram_configure_core_dpll) @@ -53,22 +55,22 @@ ENTRY(omap3_sram_configure_core_dpll) ldr r5, [sp, #56] @ load extra args from the stack ldr r6, [sp, #60] @ load extra args from the stack dsb @ flush buffered writes to interconnect - cmp r3, #0x2 - blne configure_sdrc - cmp r4, #0x1 + cmp r3, #0x2 @ if increasing SDRC clk rate, + blne configure_sdrc @ program the SDRC regs early (for RFR) + cmp r4, #0x1 @ set the intended DLL state bleq unlock_dll blne lock_dll - bl sdram_in_selfrefresh @ put the SDRAM in self refresh - bl configure_core_dpll - bl enable_sdrc - cmp r4, #0x1 + bl sdram_in_selfrefresh @ put SDRAM in self refresh, idle SDRC + bl configure_core_dpll @ change the DPLL3 M2 divider + bl enable_sdrc @ take SDRC out of idle + cmp r4, #0x1 @ wait for DLL status to change bleq wait_dll_unlock blne wait_dll_lock - cmp r3, #0x1 - beq return_to_sdram - bl configure_sdrc - mov r12, r5 @ if slowing, wait for SDRC to stabilize - bl wait_clk_stable + cmp r3, #0x1 @ if increasing SDRC clk rate, + beq return_to_sdram @ return to SDRAM code, otherwise, + bl configure_sdrc @ reprogram SDRC regs now + mov r12, r5 + bl wait_clk_stable @ wait for SDRC to stabilize return_to_sdram: isb @ prevent speculative exec past here mov r0, #0 @ return value @@ -93,6 +95,7 @@ sdram_in_selfrefresh: bic r12, r12, #0x4 @ clear PWDENA str r12, [r11] @ write back to SDRC_POWER register ldr r12, [r11] @ posted-write barrier for SDRC +idle_sdrc: ldr r11, omap3_cm_iclken1_core @ read the CM_ICLKEN1_CORE reg ldr r12, [r11] bic r12, r12, #0x2 @ disable iclk bit for SDRC -- cgit v1.2.3 From df14e4747aa58126a508ae26661c73d83127c831 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:28 -0600 Subject: OMAP3 SRAM: convert SRAM code to use macros rather than magic numbers Convert omap3_sram_configure_core_dpll() to use macros rather than magic numbers. Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/sram34xx.S | 53 ++++++++++++++++++++++++++++++------------ 1 file changed, 38 insertions(+), 15 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 37a1e1fc0ab..16eb4efa8b7 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -36,6 +36,29 @@ .text +/* r4 parameters */ +#define SDRC_NO_UNLOCK_DLL 0x0 +#define SDRC_UNLOCK_DLL 0x1 + +/* SDRC_DLLA_CTRL bit settings */ +#define DLLIDLE_MASK 0x4 + +/* SDRC_DLLA_STATUS bit settings */ +#define LOCKSTATUS_MASK 0x4 + +/* SDRC_POWER bit settings */ +#define SRFRONIDLEREQ_MASK 0x40 +#define PWDENA_MASK 0x4 + +/* CM_IDLEST1_CORE bit settings */ +#define ST_SDRC_MASK 0x2 + +/* CM_ICLKEN1_CORE bit settings */ +#define EN_SDRC_MASK 0x2 + +/* CM_CLKSEL1_PLL bit settings */ +#define CORE_DPLL_CLKOUT_DIV_SHIFT 0x1b + /* * omap3_sram_configure_core_dpll - change DPLL3 M2 divider * r0 = new SDRC_RFR_CTRL register contents @@ -57,13 +80,13 @@ ENTRY(omap3_sram_configure_core_dpll) dsb @ flush buffered writes to interconnect cmp r3, #0x2 @ if increasing SDRC clk rate, blne configure_sdrc @ program the SDRC regs early (for RFR) - cmp r4, #0x1 @ set the intended DLL state + cmp r4, #SDRC_UNLOCK_DLL @ set the intended DLL state bleq unlock_dll blne lock_dll bl sdram_in_selfrefresh @ put SDRAM in self refresh, idle SDRC bl configure_core_dpll @ change the DPLL3 M2 divider bl enable_sdrc @ take SDRC out of idle - cmp r4, #0x1 @ wait for DLL status to change + cmp r4, #SDRC_UNLOCK_DLL @ wait for DLL status to change bleq wait_dll_unlock blne wait_dll_lock cmp r3, #0x1 @ if increasing SDRC clk rate, @@ -78,33 +101,33 @@ return_to_sdram: unlock_dll: ldr r11, omap3_sdrc_dlla_ctrl ldr r12, [r11] - orr r12, r12, #0x4 + orr r12, r12, #DLLIDLE_MASK str r12, [r11] @ (no OCP barrier needed) bx lr lock_dll: ldr r11, omap3_sdrc_dlla_ctrl ldr r12, [r11] - bic r12, r12, #0x4 + bic r12, r12, #DLLIDLE_MASK str r12, [r11] @ (no OCP barrier needed) bx lr sdram_in_selfrefresh: ldr r11, omap3_sdrc_power @ read the SDRC_POWER register ldr r12, [r11] @ read the contents of SDRC_POWER mov r9, r12 @ keep a copy of SDRC_POWER bits - orr r12, r12, #0x40 @ enable self refresh on idle req - bic r12, r12, #0x4 @ clear PWDENA + orr r12, r12, #SRFRONIDLEREQ_MASK @ enable self refresh on idle + bic r12, r12, #PWDENA_MASK @ clear PWDENA str r12, [r11] @ write back to SDRC_POWER register ldr r12, [r11] @ posted-write barrier for SDRC idle_sdrc: ldr r11, omap3_cm_iclken1_core @ read the CM_ICLKEN1_CORE reg ldr r12, [r11] - bic r12, r12, #0x2 @ disable iclk bit for SDRC + bic r12, r12, #EN_SDRC_MASK @ disable iclk bit for SDRC str r12, [r11] wait_sdrc_idle: ldr r11, omap3_cm_idlest1_core ldr r12, [r11] - and r12, r12, #0x2 @ check for SDRC idle - cmp r12, #2 + and r12, r12, #ST_SDRC_MASK @ check for SDRC idle + cmp r12, #ST_SDRC_MASK bne wait_sdrc_idle bx lr configure_core_dpll: @@ -112,7 +135,7 @@ configure_core_dpll: ldr r12, [r11] ldr r10, core_m2_mask_val @ modify m2 for core dpll and r12, r12, r10 - orr r12, r12, r3, lsl #0x1B @ r3 contains the M2 val + orr r12, r12, r3, lsl #CORE_DPLL_CLKOUT_DIV_SHIFT str r12, [r11] ldr r12, [r11] @ posted-write barrier for CM bx lr @@ -123,12 +146,12 @@ wait_clk_stable: enable_sdrc: ldr r11, omap3_cm_iclken1_core ldr r12, [r11] - orr r12, r12, #0x2 @ enable iclk bit for SDRC + orr r12, r12, #EN_SDRC_MASK @ enable iclk bit for SDRC str r12, [r11] wait_sdrc_idle1: ldr r11, omap3_cm_idlest1_core ldr r12, [r11] - and r12, r12, #0x2 + and r12, r12, #ST_SDRC_MASK cmp r12, #0 bne wait_sdrc_idle1 restore_sdrc_power_val: @@ -138,14 +161,14 @@ restore_sdrc_power_val: wait_dll_lock: ldr r11, omap3_sdrc_dlla_status ldr r12, [r11] - and r12, r12, #0x4 - cmp r12, #0x4 + and r12, r12, #LOCKSTATUS_MASK + cmp r12, #LOCKSTATUS_MASK bne wait_dll_lock bx lr wait_dll_unlock: ldr r11, omap3_sdrc_dlla_status ldr r12, [r11] - and r12, r12, #0x4 + and r12, r12, #LOCKSTATUS_MASK cmp r12, #0x0 bne wait_dll_unlock bx lr -- cgit v1.2.3 From 3afec6332e1e7cf2d74e0bf08160a68f43a59073 Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Fri, 19 Jun 2009 19:08:29 -0600 Subject: OMAP3: Add support for DPLL3 divisor values higher than 2 Previously only 1 and 2 was supported. This is needed for DVFS VDD2 control. Signed-off-by: Tero Kristo --- arch/arm/mach-omap2/clock34xx.c | 9 +++------ arch/arm/mach-omap2/sram34xx.S | 8 +++++--- 2 files changed, 8 insertions(+), 9 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index cf41ab55fa9..045da923e75 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -739,9 +739,9 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) sdrcrate = sdrc_ick.rate; if (rate > clk->rate) - sdrcrate <<= ((rate / clk->rate) - 1); + sdrcrate <<= ((rate / clk->rate) >> 1); else - sdrcrate >>= ((clk->rate / rate) - 1); + sdrcrate >>= ((clk->rate / rate) >> 1); sp = omap2_sdrc_get_params(sdrcrate); if (!sp) @@ -768,12 +768,9 @@ static int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) pr_debug("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); - omap3_configure_core_dpll(sp->rfr_ctrl, sp->actim_ctrla, sp->actim_ctrlb, new_div, unlock_dll, c, - sp->mr); + sp->mr, rate > clk->rate); return 0; } diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 16eb4efa8b7..487fa8609cd 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -70,6 +70,7 @@ * r5 = number of MPU cycles to wait for SDRC to stabilize after * reprogramming the SDRC when switching to a slower MPU speed * r6 = new SDRC_MR_0 register value + * r7 = increasing SDRC rate? (1 = yes, 0 = no) * */ ENTRY(omap3_sram_configure_core_dpll) @@ -77,9 +78,10 @@ ENTRY(omap3_sram_configure_core_dpll) ldr r4, [sp, #52] @ pull extra args off the stack ldr r5, [sp, #56] @ load extra args from the stack ldr r6, [sp, #60] @ load extra args from the stack + ldr r7, [sp, #64] @ load extra args from the stack dsb @ flush buffered writes to interconnect - cmp r3, #0x2 @ if increasing SDRC clk rate, - blne configure_sdrc @ program the SDRC regs early (for RFR) + cmp r7, #1 @ if increasing SDRC clk rate, + bleq configure_sdrc @ program the SDRC regs early (for RFR) cmp r4, #SDRC_UNLOCK_DLL @ set the intended DLL state bleq unlock_dll blne lock_dll @@ -89,7 +91,7 @@ ENTRY(omap3_sram_configure_core_dpll) cmp r4, #SDRC_UNLOCK_DLL @ wait for DLL status to change bleq wait_dll_unlock blne wait_dll_lock - cmp r3, #0x1 @ if increasing SDRC clk rate, + cmp r7, #1 @ if increasing SDRC clk rate, beq return_to_sdram @ return to SDRAM code, otherwise, bl configure_sdrc @ reprogram SDRC regs now mov r12, r5 -- cgit v1.2.3 From 7b7bcefa35d62fec64c3615a6bef7866f34c7cc9 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Fri, 19 Jun 2009 19:08:29 -0600 Subject: OMAP3 SDRC: set FIXEDDELAY when disabling SDRC DLL Correspondence with the TI OMAP hardware team indicates that SDRC_DLLA_CTRL.FIXEDDELAY should be initialized to 0x0f. This number was apparently derived from process validation. This is only used when the SDRC DLL is unlocked (e.g., SDRC clock frequency less than 83MHz). Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/sram34xx.S | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 487fa8609cd..f41f8d96ddb 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -41,8 +41,18 @@ #define SDRC_UNLOCK_DLL 0x1 /* SDRC_DLLA_CTRL bit settings */ +#define FIXEDDELAY_SHIFT 24 +#define FIXEDDELAY_MASK (0xff << FIXEDDELAY_SHIFT) #define DLLIDLE_MASK 0x4 +/* + * SDRC_DLLA_CTRL default values: TI hardware team indicates that + * FIXEDDELAY should be initialized to 0xf. This apparently was + * empirically determined during process testing, so no derivation + * was provided. + */ +#define FIXEDDELAY_DEFAULT (0x0f << FIXEDDELAY_SHIFT) + /* SDRC_DLLA_STATUS bit settings */ #define LOCKSTATUS_MASK 0x4 @@ -103,6 +113,8 @@ return_to_sdram: unlock_dll: ldr r11, omap3_sdrc_dlla_ctrl ldr r12, [r11] + and r12, r12, #FIXEDDELAY_MASK + orr r12, r12, #FIXEDDELAY_DEFAULT orr r12, r12, #DLLIDLE_MASK str r12, [r11] @ (no OCP barrier needed) bx lr -- cgit v1.2.3 From 2687069f3ac297b820c58de7222e4d16adbca498 Mon Sep 17 00:00:00 2001 From: Roel Kluin Date: Fri, 19 Jun 2009 19:08:30 -0600 Subject: OMAP2 clock/powerdomain: off by 1 error in loop timeout comparisons with while (i++ < MAX_CLOCK_ENABLE_WAIT); i can reach MAX_CLOCK_ENABLE_WAIT + 1 after the loop, so if (i == MAX_CLOCK_ENABLE_WAIT) that's still success. Signed-off-by: Roel Kluin Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/clock.c | 2 +- arch/arm/mach-omap2/powerdomain.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm/mach-omap2') diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index ba528f85749..b0665f161c0 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -302,7 +302,7 @@ int omap2_wait_clock_ready(void __iomem *reg, u32 mask, const char *name) udelay(1); } - if (i < MAX_CLOCK_ENABLE_WAIT) + if (i <= MAX_CLOCK_ENABLE_WAIT) pr_debug("Clock %s stable after %d loops\n", name, i); else printk(KERN_ERR "Clock %s didn't enable in %d tries\n", diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c index 73e2971b175..983f1cb676b 100644 --- a/arch/arm/mach-omap2/powerdomain.c +++ b/arch/arm/mach-omap2/powerdomain.c @@ -1099,7 +1099,7 @@ int pwrdm_wait_transition(struct powerdomain *pwrdm) (c++ < PWRDM_TRANSITION_BAILOUT)) udelay(1); - if (c >= PWRDM_TRANSITION_BAILOUT) { + if (c > PWRDM_TRANSITION_BAILOUT) { printk(KERN_ERR "powerdomain: waited too long for " "powerdomain %s to complete transition\n", pwrdm->name); return -EAGAIN; -- cgit v1.2.3