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authorPaul Walmsley <paul@pwsan.com>2009-07-24 21:44:03 -0400
committerpaul <paul@twilight.(none)>2009-07-24 22:10:35 -0400
commit72350b29a4c0debfc27c2edbeed9b4ff3f935dd4 (patch)
tree0c4637987fdbe97bfbdab7e00031283af47aadc1 /arch/arm/mach-omap2/clock.c
parentdf56556e571234cf26072cd58c01ac3520986b44 (diff)
OMAP2/3 clock: split, rename omap2_wait_clock_ready()
Some OMAP2/3 hardware modules have CM_IDLEST attributes that are not handled by the current omap2_wait_clock_ready() code. In preparation for patches that fix the unusual devices, rename the function omap2_wait_clock_ready() to omap2_wait_module_ready() and split it into three parts: 1. A clkops-specific companion clock return function (by default, omap2_clk_dflt_find_companion()) 2. A clkops-specific CM_IDLEST register address and bit shift return function (by default, omap2_clk_dflt_find_idlest()) 3. Code to wait for the CM to indicate that the module is ready (omap2_cm_wait_idlest()) Clocks can now specify their own custom find_companion() and find_idlest() functions; used in subsequent patches. Signed-off-by: Paul Walmsley <paul@pwsan.com>
Diffstat (limited to 'arch/arm/mach-omap2/clock.c')
-rw-r--r--arch/arm/mach-omap2/clock.c156
1 files changed, 79 insertions, 77 deletions
diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
index b0665f161c03..456e2ad5f621 100644
--- a/arch/arm/mach-omap2/clock.c
+++ b/arch/arm/mach-omap2/clock.c
@@ -27,6 +27,7 @@
27#include <mach/clock.h> 27#include <mach/clock.h>
28#include <mach/clockdomain.h> 28#include <mach/clockdomain.h>
29#include <mach/cpu.h> 29#include <mach/cpu.h>
30#include <mach/prcm.h>
30#include <asm/div64.h> 31#include <asm/div64.h>
31 32
32#include <mach/sdrc.h> 33#include <mach/sdrc.h>
@@ -38,8 +39,6 @@
38#include "cm-regbits-24xx.h" 39#include "cm-regbits-24xx.h"
39#include "cm-regbits-34xx.h" 40#include "cm-regbits-34xx.h"
40 41
41#define MAX_CLOCK_ENABLE_WAIT 100000
42
43/* DPLL rate rounding: minimum DPLL multiplier, divider values */ 42/* DPLL rate rounding: minimum DPLL multiplier, divider values */
44#define DPLL_MIN_MULTIPLIER 1 43#define DPLL_MIN_MULTIPLIER 1
45#define DPLL_MIN_DIVIDER 1 44#define DPLL_MIN_DIVIDER 1
@@ -274,83 +273,97 @@ unsigned long omap2_fixed_divisor_recalc(struct clk *clk)
274} 273}
275 274
276/** 275/**
277 * omap2_wait_clock_ready - wait for clock to enable 276 * omap2_clk_dflt_find_companion - find companion clock to @clk
278 * @reg: physical address of clock IDLEST register 277 * @clk: struct clk * to find the companion clock of
279 * @mask: value to mask against to determine if the clock is active 278 * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in
280 * @name: name of the clock (for printk) 279 * @other_bit: u8 ** to return the companion clock bit shift in
280 *
281 * Note: We don't need special code here for INVERT_ENABLE for the
282 * time being since INVERT_ENABLE only applies to clocks enabled by
283 * CM_CLKEN_PLL
281 * 284 *
282 * Returns 1 if the clock enabled in time, or 0 if it failed to enable 285 * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes it's
283 * in roughly MAX_CLOCK_ENABLE_WAIT microseconds. 286 * just a matter of XORing the bits.
287 *
288 * Some clocks don't have companion clocks. For example, modules with
289 * only an interface clock (such as MAILBOXES) don't have a companion
290 * clock. Right now, this code relies on the hardware exporting a bit
291 * in the correct companion register that indicates that the
292 * nonexistent 'companion clock' is active. Future patches will
293 * associate this type of code with per-module data structures to
294 * avoid this issue, and remove the casts. No return value.
284 */ 295 */
285int omap2_wait_clock_ready(void __iomem *reg, u32 mask, const char *name) 296void omap2_clk_dflt_find_companion(struct clk *clk, void __iomem **other_reg,
297 u8 *other_bit)
286{ 298{
287 int i = 0; 299 u32 r;
288 int ena = 0;
289 300
290 /* 301 /*
291 * 24xx uses 0 to indicate not ready, and 1 to indicate ready. 302 * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes
292 * 34xx reverses this, just to keep us on our toes 303 * it's just a matter of XORing the bits.
293 */ 304 */
294 if (cpu_mask & (RATE_IN_242X | RATE_IN_243X)) 305 r = ((__force u32)clk->enable_reg ^ (CM_FCLKEN ^ CM_ICLKEN));
295 ena = mask;
296 else if (cpu_mask & RATE_IN_343X)
297 ena = 0;
298
299 /* Wait for lock */
300 while (((__raw_readl(reg) & mask) != ena) &&
301 (i++ < MAX_CLOCK_ENABLE_WAIT)) {
302 udelay(1);
303 }
304
305 if (i <= MAX_CLOCK_ENABLE_WAIT)
306 pr_debug("Clock %s stable after %d loops\n", name, i);
307 else
308 printk(KERN_ERR "Clock %s didn't enable in %d tries\n",
309 name, MAX_CLOCK_ENABLE_WAIT);
310
311
312 return (i < MAX_CLOCK_ENABLE_WAIT) ? 1 : 0;
313};
314 306
307 *other_reg = (__force void __iomem *)r;
308 *other_bit = clk->enable_bit;
309}
315 310
316/* 311/**
317 * Note: We don't need special code here for INVERT_ENABLE 312 * omap2_clk_dflt_find_idlest - find CM_IDLEST reg va, bit shift for @clk
318 * for the time being since INVERT_ENABLE only applies to clocks enabled by 313 * @clk: struct clk * to find IDLEST info for
319 * CM_CLKEN_PLL 314 * @idlest_reg: void __iomem ** to return the CM_IDLEST va in
315 * @idlest_bit: u8 ** to return the CM_IDLEST bit shift in
316 *
317 * Return the CM_IDLEST register address and bit shift corresponding
318 * to the module that "owns" this clock. This default code assumes
319 * that the CM_IDLEST bit shift is the CM_*CLKEN bit shift, and that
320 * the IDLEST register address ID corresponds to the CM_*CLKEN
321 * register address ID (e.g., that CM_FCLKEN2 corresponds to
322 * CM_IDLEST2). This is not true for all modules. No return value.
320 */ 323 */
321static void omap2_clk_wait_ready(struct clk *clk) 324void omap2_clk_dflt_find_idlest(struct clk *clk, void __iomem **idlest_reg,
325 u8 *idlest_bit)
322{ 326{
323 void __iomem *reg, *other_reg, *st_reg; 327 u32 r;
324 u32 bit;
325 328
326 /* 329 r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
327 * REVISIT: This code is pretty ugly. It would be nice to generalize 330 *idlest_reg = (__force void __iomem *)r;
328 * it and pull it into struct clk itself somehow. 331 *idlest_bit = clk->enable_bit;
329 */ 332}
330 reg = clk->enable_reg;
331 333
332 /* 334/**
333 * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes 335 * omap2_module_wait_ready - wait for an OMAP module to leave IDLE
334 * it's just a matter of XORing the bits. 336 * @clk: struct clk * belonging to the module
335 */ 337 *
336 other_reg = (void __iomem *)((u32)reg ^ (CM_FCLKEN ^ CM_ICLKEN)); 338 * If the necessary clocks for the OMAP hardware IP block that
339 * corresponds to clock @clk are enabled, then wait for the module to
340 * indicate readiness (i.e., to leave IDLE). This code does not
341 * belong in the clock code and will be moved in the medium term to
342 * module-dependent code. No return value.
343 */
344static void omap2_module_wait_ready(struct clk *clk)
345{
346 void __iomem *companion_reg, *idlest_reg;
347 u8 other_bit, idlest_bit;
348
349 /* Not all modules have multiple clocks that their IDLEST depends on */
350 if (clk->ops->find_companion) {
351 clk->ops->find_companion(clk, &companion_reg, &other_bit);
352 if (!(__raw_readl(companion_reg) & (1 << other_bit)))
353 return;
354 }
337 355
338 /* Check if both functional and interface clocks 356 clk->ops->find_idlest(clk, &idlest_reg, &idlest_bit);
339 * are running. */
340 bit = 1 << clk->enable_bit;
341 if (!(__raw_readl(other_reg) & bit))
342 return;
343 st_reg = (void __iomem *)(((u32)other_reg & ~0xf0) | 0x20); /* CM_IDLEST* */
344 357
345 omap2_wait_clock_ready(st_reg, bit, clk->name); 358 omap2_cm_wait_idlest(idlest_reg, (1 << idlest_bit), clk->name);
346} 359}
347 360
348static int omap2_dflt_clk_enable(struct clk *clk) 361int omap2_dflt_clk_enable(struct clk *clk)
349{ 362{
350 u32 v; 363 u32 v;
351 364
352 if (unlikely(clk->enable_reg == NULL)) { 365 if (unlikely(clk->enable_reg == NULL)) {
353 printk(KERN_ERR "clock.c: Enable for %s without enable code\n", 366 pr_err("clock.c: Enable for %s without enable code\n",
354 clk->name); 367 clk->name);
355 return 0; /* REVISIT: -EINVAL */ 368 return 0; /* REVISIT: -EINVAL */
356 } 369 }
@@ -363,26 +376,13 @@ static int omap2_dflt_clk_enable(struct clk *clk)
363 __raw_writel(v, clk->enable_reg); 376 __raw_writel(v, clk->enable_reg);
364 v = __raw_readl(clk->enable_reg); /* OCP barrier */ 377 v = __raw_readl(clk->enable_reg); /* OCP barrier */
365 378
366 return 0; 379 if (clk->ops->find_idlest)
367} 380 omap2_module_wait_ready(clk);
368 381
369static int omap2_dflt_clk_enable_wait(struct clk *clk) 382 return 0;
370{
371 int ret;
372
373 if (!clk->enable_reg) {
374 printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
375 clk->name);
376 return 0; /* REVISIT: -EINVAL */
377 }
378
379 ret = omap2_dflt_clk_enable(clk);
380 if (ret == 0)
381 omap2_clk_wait_ready(clk);
382 return ret;
383} 383}
384 384
385static void omap2_dflt_clk_disable(struct clk *clk) 385void omap2_dflt_clk_disable(struct clk *clk)
386{ 386{
387 u32 v; 387 u32 v;
388 388
@@ -406,8 +406,10 @@ static void omap2_dflt_clk_disable(struct clk *clk)
406} 406}
407 407
408const struct clkops clkops_omap2_dflt_wait = { 408const struct clkops clkops_omap2_dflt_wait = {
409 .enable = omap2_dflt_clk_enable_wait, 409 .enable = omap2_dflt_clk_enable,
410 .disable = omap2_dflt_clk_disable, 410 .disable = omap2_dflt_clk_disable,
411 .find_companion = omap2_clk_dflt_find_companion,
412 .find_idlest = omap2_clk_dflt_find_idlest,
411}; 413};
412 414
413const struct clkops clkops_omap2_dflt = { 415const struct clkops clkops_omap2_dflt = {