From 137b3ee27ab1b27dba081542476054836978ca45 Mon Sep 17 00:00:00 2001 From: Hiroshi DOYU Date: Thu, 3 Jul 2008 12:24:41 +0300 Subject: ARM: OMAP: CLKFW: Initial debugfs support for omap clock framework debugfs can provide the infrastructure to trace the dependencies of clock tree hierarchy quite visibly. This patch enables to keep track of clock tree hierarchy and expose their attributes under each clock directry as below: omap:~# tree -d -L 2 /debug/clock/omap_32k_fck/ /debug/clock/omap_32k_fck/ |-- gpt10_fck |-- gpt11_fck |-- gpt1_fck |-- per_32k_alwon_fck | |-- gpio2_fck | |-- gpio3_fck | |-- gpio4_fck | |-- gpio5_fck | |-- gpio6_fck | `-- wdt3_fck |-- ts_fck `-- wkup_32k_fck |-- gpio1_fck `-- wdt2_fck 14 directories omap:~# tree /debug/clock/omap_32k_fck/gpt10_fck/ /debug/clock/omap_32k_fck/gpt10_fck/ |-- flags |-- rate `-- usecount 0 directories, 3 files Although, compared with David Brownell's small patch, this may look bit overkilling, I expect that this debugfs can deal with other PRCM complexities at the same time. For example, powerdomain dependencies can be expressed by using symbolic links of these clocks if powerdomain supports dubgfs as well. Signed-off-by: Hiroshi DOYU Signed-off-by: Tony Lindgren --- include/asm-arm/arch-omap/clock.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/asm-arm/arch-omap/clock.h') diff --git a/include/asm-arm/arch-omap/clock.h b/include/asm-arm/arch-omap/clock.h index 12a5e4de951..8490fbba39d 100644 --- a/include/asm-arm/arch-omap/clock.h +++ b/include/asm-arm/arch-omap/clock.h @@ -71,6 +71,9 @@ struct clk { __u8 rate_offset; __u8 src_offset; #endif +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) + struct dentry *dent; /* For visible tree hierarchy */ +#endif }; struct cpufreq_frequency_table; -- cgit v1.2.3 From 542313cc98e72d026d2df86f515699dfaface460 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 3 Jul 2008 12:24:45 +0300 Subject: ARM: OMAP2: Clock: Add OMAP3 DPLL autoidle functions This patch adds support for DPLL autoidle control to the OMAP3 clock framework. These functions will be used by the noncore DPLL enable and disable code - this is because, according to the CDP code, the DPLL autoidle status must be saved and restored across DPLL lock/bypass/off transitions. N.B.: the CORE DPLL (DPLL3) has three autoidle mode options, rather than just two. This code currently does not support the third option, low-power bypass autoidle. Signed-off-by: Paul Walmsley Signed-off-by: Tony Lindgren --- include/asm-arm/arch-omap/clock.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/asm-arm/arch-omap/clock.h') diff --git a/include/asm-arm/arch-omap/clock.h b/include/asm-arm/arch-omap/clock.h index 8490fbba39d..22daa5d64d3 100644 --- a/include/asm-arm/arch-omap/clock.h +++ b/include/asm-arm/arch-omap/clock.h @@ -34,11 +34,16 @@ struct dpll_data { u32 mult_mask; u32 div1_mask; # if defined(CONFIG_ARCH_OMAP3) + u8 modes; void __iomem *control_reg; u32 enable_mask; u8 auto_recal_bit; u8 recal_en_bit; u8 recal_st_bit; + void __iomem *autoidle_reg; + u32 autoidle_mask; + void __iomem *idlest_reg; + u8 idlest_bit; # endif }; -- cgit v1.2.3 From 88b8ba90570067178d32c654ad95786041e86e86 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 3 Jul 2008 12:24:46 +0300 Subject: ARM: OMAP2: Clock: New OMAP2/3 DPLL rate rounding algorithm This patch adds a new rate rounding algorithm for DPLL clocks on the OMAP2/3 architecture. For a desired DPLL target rate, there may be several multiplier/divider (M, N) values which will generate a sufficiently close rate. Lower N values result in greater power economy. However, lower N values can cause the difference between the rounded rate and the target rate ("rate error") to be larger than it would be with a higher N. This can cause downstream devices to run more slowly than they otherwise would. This DPLL rate rounding algorithm: - attempts to find the lowest possible N (DPLL divider) to reach the target_rate (since, according to Richard Woodruff , lower N values save more power than higher N values). - allows developers to set an upper bound on the error between the rounded rate and the desired target rate ("rate tolerance"), so an appropriate balance between rate fidelity and power savings can be set. This maximum rate error tolerance is set via omap2_set_dpll_rate_tolerance(). - never returns a rounded rate higher than the target rate. The rate rounding algorithm caches the last rounded M, N, and rate computation to avoid rounding the rate twice for each clk_set_rate() call. (This patch does not yet implement set_rate for DPLLs; that follows in a future patch.) The algorithm trades execution speed for rate accuracy. It will find the (M, N) set that results in the least rate error, within a specified rate tolerance. It does this by evaluating each divider setting - on OMAP3, this involves 128 steps. Another approach to DPLL rate rounding would be to bail out as soon as a valid rate is found within the rate tolerance, which would trade rate accuracy for execution speed. Alternate implementations welcome. This code is not yet used by the OMAP24XX DPLL clock, since it is currently defined as a composite clock, fusing the DPLL M,N and the M2 output divider. This patch also renames the existing OMAP24xx DPLL programming functions to highlight that they program both the DPLL and the DPLL's output multiplier. Signed-off-by: Paul Walmsley Signed-off-by: Tony Lindgren --- include/asm-arm/arch-omap/clock.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/asm-arm/arch-omap/clock.h') diff --git a/include/asm-arm/arch-omap/clock.h b/include/asm-arm/arch-omap/clock.h index 22daa5d64d3..4c7b3514f71 100644 --- a/include/asm-arm/arch-omap/clock.h +++ b/include/asm-arm/arch-omap/clock.h @@ -33,6 +33,13 @@ struct dpll_data { void __iomem *mult_div1_reg; u32 mult_mask; u32 div1_mask; + u16 last_rounded_m; + u8 last_rounded_n; + unsigned long last_rounded_rate; + unsigned int rate_tolerance; + u16 max_multiplier; + u8 max_divider; + u32 max_tolerance; # if defined(CONFIG_ARCH_OMAP3) u8 modes; void __iomem *control_reg; @@ -71,7 +78,7 @@ struct clk { void __iomem *clksel_reg; u32 clksel_mask; const struct clksel *clksel; - const struct dpll_data *dpll_data; + struct dpll_data *dpll_data; #else __u8 rate_offset; __u8 src_offset; -- cgit v1.2.3