clock.c 30 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137
  1. /*
  2. * arch/arm/mach-lpc32xx/clock.c
  3. *
  4. * Author: Kevin Wells <kevin.wells@nxp.com>
  5. *
  6. * Copyright (C) 2010 NXP Semiconductors
  7. *
  8. * This program is free software; you can redistribute it and/or modify
  9. * it under the terms of the GNU General Public License as published by
  10. * the Free Software Foundation; either version 2 of the License, or
  11. * (at your option) any later version.
  12. *
  13. * This program is distributed in the hope that it will be useful,
  14. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. * GNU General Public License for more details.
  17. */
  18. /*
  19. * LPC32xx clock management driver overview
  20. *
  21. * The LPC32XX contains a number of high level system clocks that can be
  22. * generated from different sources. These system clocks are used to
  23. * generate the CPU and bus rates and the individual peripheral clocks in
  24. * the system. When Linux is started by the boot loader, the system
  25. * clocks are already running. Stopping a system clock during normal
  26. * Linux operation should never be attempted, as peripherals that require
  27. * those clocks will quit working (ie, DRAM).
  28. *
  29. * The LPC32xx high level clock tree looks as follows. Clocks marked with
  30. * an asterisk are always on and cannot be disabled. Clocks marked with
  31. * an ampersand can only be disabled in CPU suspend mode. Clocks marked
  32. * with a caret are always on if it is the selected clock for the SYSCLK
  33. * source. The clock that isn't used for SYSCLK can be enabled and
  34. * disabled normally.
  35. * 32KHz oscillator*
  36. * / | \
  37. * RTC* PLL397^ TOUCH
  38. * /
  39. * Main oscillator^ /
  40. * | \ /
  41. * | SYSCLK&
  42. * | \
  43. * | \
  44. * USB_PLL HCLK_PLL&
  45. * | | |
  46. * USB host/device PCLK& |
  47. * | |
  48. * Peripherals
  49. *
  50. * The CPU and chip bus rates are derived from the HCLK PLL, which can
  51. * generate various clock rates up to 266MHz and beyond. The internal bus
  52. * rates (PCLK and HCLK) are generated from dividers based on the HCLK
  53. * PLL rate. HCLK can be a ratio of 1:1, 1:2, or 1:4 or HCLK PLL rate,
  54. * while PCLK can be 1:1 to 1:32 of HCLK PLL rate. Most peripherals high
  55. * level clocks are based on either HCLK or PCLK, but have their own
  56. * dividers as part of the IP itself. Because of this, the system clock
  57. * rates should not be changed.
  58. *
  59. * The HCLK PLL is clocked from SYSCLK, which can be derived from the
  60. * main oscillator or PLL397. PLL397 generates a rate that is 397 times
  61. * the 32KHz oscillator rate. The main oscillator runs at the selected
  62. * oscillator/crystal rate on the mosc_in pin of the LPC32xx. This rate
  63. * is normally 13MHz, but depends on the selection of external crystals
  64. * or oscillators. If USB operation is required, the main oscillator must
  65. * be used in the system.
  66. *
  67. * Switching SYSCLK between sources during normal Linux operation is not
  68. * supported. SYSCLK is preset in the bootloader. Because of the
  69. * complexities of clock management during clock frequency changes,
  70. * there are some limitations to the clock driver explained below:
  71. * - The PLL397 and main oscillator can be enabled and disabled by the
  72. * clk_enable() and clk_disable() functions unless SYSCLK is based
  73. * on that clock. This allows the other oscillator that isn't driving
  74. * the HCLK PLL to be used as another system clock that can be routed
  75. * to an external pin.
  76. * - The muxed SYSCLK input and HCLK_PLL rate cannot be changed with
  77. * this driver.
  78. * - HCLK and PCLK rates cannot be changed as part of this driver.
  79. * - Most peripherals have their own dividers are part of the peripheral
  80. * block. Changing SYSCLK, HCLK PLL, HCLK, or PCLK sources or rates
  81. * will also impact the individual peripheral rates.
  82. */
  83. #include <linux/kernel.h>
  84. #include <linux/list.h>
  85. #include <linux/errno.h>
  86. #include <linux/device.h>
  87. #include <linux/err.h>
  88. #include <linux/clk.h>
  89. #include <linux/amba/bus.h>
  90. #include <linux/amba/clcd.h>
  91. #include <mach/hardware.h>
  92. #include <asm/clkdev.h>
  93. #include <mach/clkdev.h>
  94. #include <mach/platform.h>
  95. #include "clock.h"
  96. #include "common.h"
  97. static struct clk clk_armpll;
  98. static struct clk clk_usbpll;
  99. static DEFINE_MUTEX(clkm_lock);
  100. /*
  101. * Post divider values for PLLs based on selected register value
  102. */
  103. static const u32 pll_postdivs[4] = {1, 2, 4, 8};
  104. static unsigned long local_return_parent_rate(struct clk *clk)
  105. {
  106. /*
  107. * If a clock has a rate of 0, then it inherits it's parent
  108. * clock rate
  109. */
  110. while (clk->rate == 0)
  111. clk = clk->parent;
  112. return clk->rate;
  113. }
  114. /* 32KHz clock has a fixed rate and is not stoppable */
  115. static struct clk osc_32KHz = {
  116. .rate = LPC32XX_CLOCK_OSC_FREQ,
  117. .get_rate = local_return_parent_rate,
  118. };
  119. static int local_pll397_enable(struct clk *clk, int enable)
  120. {
  121. u32 reg;
  122. unsigned long timeout = 1 + msecs_to_jiffies(10);
  123. reg = __raw_readl(LPC32XX_CLKPWR_PLL397_CTRL);
  124. if (enable == 0) {
  125. reg |= LPC32XX_CLKPWR_SYSCTRL_PLL397_DIS;
  126. __raw_writel(reg, LPC32XX_CLKPWR_PLL397_CTRL);
  127. } else {
  128. /* Enable PLL397 */
  129. reg &= ~LPC32XX_CLKPWR_SYSCTRL_PLL397_DIS;
  130. __raw_writel(reg, LPC32XX_CLKPWR_PLL397_CTRL);
  131. /* Wait for PLL397 lock */
  132. while (((__raw_readl(LPC32XX_CLKPWR_PLL397_CTRL) &
  133. LPC32XX_CLKPWR_SYSCTRL_PLL397_STS) == 0) &&
  134. (timeout > jiffies))
  135. cpu_relax();
  136. if ((__raw_readl(LPC32XX_CLKPWR_PLL397_CTRL) &
  137. LPC32XX_CLKPWR_SYSCTRL_PLL397_STS) == 0)
  138. return -ENODEV;
  139. }
  140. return 0;
  141. }
  142. static int local_oscmain_enable(struct clk *clk, int enable)
  143. {
  144. u32 reg;
  145. unsigned long timeout = 1 + msecs_to_jiffies(10);
  146. reg = __raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL);
  147. if (enable == 0) {
  148. reg |= LPC32XX_CLKPWR_MOSC_DISABLE;
  149. __raw_writel(reg, LPC32XX_CLKPWR_MAIN_OSC_CTRL);
  150. } else {
  151. /* Enable main oscillator */
  152. reg &= ~LPC32XX_CLKPWR_MOSC_DISABLE;
  153. __raw_writel(reg, LPC32XX_CLKPWR_MAIN_OSC_CTRL);
  154. /* Wait for main oscillator to start */
  155. while (((__raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL) &
  156. LPC32XX_CLKPWR_MOSC_DISABLE) != 0) &&
  157. (timeout > jiffies))
  158. cpu_relax();
  159. if ((__raw_readl(LPC32XX_CLKPWR_MAIN_OSC_CTRL) &
  160. LPC32XX_CLKPWR_MOSC_DISABLE) != 0)
  161. return -ENODEV;
  162. }
  163. return 0;
  164. }
  165. static struct clk osc_pll397 = {
  166. .parent = &osc_32KHz,
  167. .enable = local_pll397_enable,
  168. .rate = LPC32XX_CLOCK_OSC_FREQ * 397,
  169. .get_rate = local_return_parent_rate,
  170. };
  171. static struct clk osc_main = {
  172. .enable = local_oscmain_enable,
  173. .rate = LPC32XX_MAIN_OSC_FREQ,
  174. .get_rate = local_return_parent_rate,
  175. };
  176. static struct clk clk_sys;
  177. /*
  178. * Convert a PLL register value to a PLL output frequency
  179. */
  180. u32 clk_get_pllrate_from_reg(u32 inputclk, u32 regval)
  181. {
  182. struct clk_pll_setup pllcfg;
  183. pllcfg.cco_bypass_b15 = 0;
  184. pllcfg.direct_output_b14 = 0;
  185. pllcfg.fdbk_div_ctrl_b13 = 0;
  186. if ((regval & LPC32XX_CLKPWR_HCLKPLL_CCO_BYPASS) != 0)
  187. pllcfg.cco_bypass_b15 = 1;
  188. if ((regval & LPC32XX_CLKPWR_HCLKPLL_POSTDIV_BYPASS) != 0)
  189. pllcfg.direct_output_b14 = 1;
  190. if ((regval & LPC32XX_CLKPWR_HCLKPLL_FDBK_SEL_FCLK) != 0)
  191. pllcfg.fdbk_div_ctrl_b13 = 1;
  192. pllcfg.pll_m = 1 + ((regval >> 1) & 0xFF);
  193. pllcfg.pll_n = 1 + ((regval >> 9) & 0x3);
  194. pllcfg.pll_p = pll_postdivs[((regval >> 11) & 0x3)];
  195. return clk_check_pll_setup(inputclk, &pllcfg);
  196. }
  197. /*
  198. * Setup the HCLK PLL with a PLL structure
  199. */
  200. static u32 local_clk_pll_setup(struct clk_pll_setup *PllSetup)
  201. {
  202. u32 tv, tmp = 0;
  203. if (PllSetup->analog_on != 0)
  204. tmp |= LPC32XX_CLKPWR_HCLKPLL_POWER_UP;
  205. if (PllSetup->cco_bypass_b15 != 0)
  206. tmp |= LPC32XX_CLKPWR_HCLKPLL_CCO_BYPASS;
  207. if (PllSetup->direct_output_b14 != 0)
  208. tmp |= LPC32XX_CLKPWR_HCLKPLL_POSTDIV_BYPASS;
  209. if (PllSetup->fdbk_div_ctrl_b13 != 0)
  210. tmp |= LPC32XX_CLKPWR_HCLKPLL_FDBK_SEL_FCLK;
  211. tv = ffs(PllSetup->pll_p) - 1;
  212. if ((!is_power_of_2(PllSetup->pll_p)) || (tv > 3))
  213. return 0;
  214. tmp |= LPC32XX_CLKPWR_HCLKPLL_POSTDIV_2POW(tv);
  215. tmp |= LPC32XX_CLKPWR_HCLKPLL_PREDIV_PLUS1(PllSetup->pll_n - 1);
  216. tmp |= LPC32XX_CLKPWR_HCLKPLL_PLLM(PllSetup->pll_m - 1);
  217. return tmp;
  218. }
  219. /*
  220. * Update the ARM core PLL frequency rate variable from the actual PLL setting
  221. */
  222. static void local_update_armpll_rate(void)
  223. {
  224. u32 clkin, pllreg;
  225. clkin = clk_armpll.parent->rate;
  226. pllreg = __raw_readl(LPC32XX_CLKPWR_HCLKPLL_CTRL) & 0x1FFFF;
  227. clk_armpll.rate = clk_get_pllrate_from_reg(clkin, pllreg);
  228. }
  229. /*
  230. * Find a PLL configuration for the selected input frequency
  231. */
  232. static u32 local_clk_find_pll_cfg(u32 pllin_freq, u32 target_freq,
  233. struct clk_pll_setup *pllsetup)
  234. {
  235. u32 ifreq, freqtol, m, n, p, fclkout;
  236. /* Determine frequency tolerance limits */
  237. freqtol = target_freq / 250;
  238. ifreq = pllin_freq;
  239. /* Is direct bypass mode possible? */
  240. if (abs(pllin_freq - target_freq) <= freqtol) {
  241. pllsetup->analog_on = 0;
  242. pllsetup->cco_bypass_b15 = 1;
  243. pllsetup->direct_output_b14 = 1;
  244. pllsetup->fdbk_div_ctrl_b13 = 1;
  245. pllsetup->pll_p = pll_postdivs[0];
  246. pllsetup->pll_n = 1;
  247. pllsetup->pll_m = 1;
  248. return clk_check_pll_setup(ifreq, pllsetup);
  249. } else if (target_freq <= ifreq) {
  250. pllsetup->analog_on = 0;
  251. pllsetup->cco_bypass_b15 = 1;
  252. pllsetup->direct_output_b14 = 0;
  253. pllsetup->fdbk_div_ctrl_b13 = 1;
  254. pllsetup->pll_n = 1;
  255. pllsetup->pll_m = 1;
  256. for (p = 0; p <= 3; p++) {
  257. pllsetup->pll_p = pll_postdivs[p];
  258. fclkout = clk_check_pll_setup(ifreq, pllsetup);
  259. if (abs(target_freq - fclkout) <= freqtol)
  260. return fclkout;
  261. }
  262. }
  263. /* Is direct mode possible? */
  264. pllsetup->analog_on = 1;
  265. pllsetup->cco_bypass_b15 = 0;
  266. pllsetup->direct_output_b14 = 1;
  267. pllsetup->fdbk_div_ctrl_b13 = 0;
  268. pllsetup->pll_p = pll_postdivs[0];
  269. for (m = 1; m <= 256; m++) {
  270. for (n = 1; n <= 4; n++) {
  271. /* Compute output frequency for this value */
  272. pllsetup->pll_n = n;
  273. pllsetup->pll_m = m;
  274. fclkout = clk_check_pll_setup(ifreq,
  275. pllsetup);
  276. if (abs(target_freq - fclkout) <=
  277. freqtol)
  278. return fclkout;
  279. }
  280. }
  281. /* Is integer mode possible? */
  282. pllsetup->analog_on = 1;
  283. pllsetup->cco_bypass_b15 = 0;
  284. pllsetup->direct_output_b14 = 0;
  285. pllsetup->fdbk_div_ctrl_b13 = 1;
  286. for (m = 1; m <= 256; m++) {
  287. for (n = 1; n <= 4; n++) {
  288. for (p = 0; p < 4; p++) {
  289. /* Compute output frequency */
  290. pllsetup->pll_p = pll_postdivs[p];
  291. pllsetup->pll_n = n;
  292. pllsetup->pll_m = m;
  293. fclkout = clk_check_pll_setup(
  294. ifreq, pllsetup);
  295. if (abs(target_freq - fclkout) <= freqtol)
  296. return fclkout;
  297. }
  298. }
  299. }
  300. /* Try non-integer mode */
  301. pllsetup->analog_on = 1;
  302. pllsetup->cco_bypass_b15 = 0;
  303. pllsetup->direct_output_b14 = 0;
  304. pllsetup->fdbk_div_ctrl_b13 = 0;
  305. for (m = 1; m <= 256; m++) {
  306. for (n = 1; n <= 4; n++) {
  307. for (p = 0; p < 4; p++) {
  308. /* Compute output frequency */
  309. pllsetup->pll_p = pll_postdivs[p];
  310. pllsetup->pll_n = n;
  311. pllsetup->pll_m = m;
  312. fclkout = clk_check_pll_setup(
  313. ifreq, pllsetup);
  314. if (abs(target_freq - fclkout) <= freqtol)
  315. return fclkout;
  316. }
  317. }
  318. }
  319. return 0;
  320. }
  321. static struct clk clk_armpll = {
  322. .parent = &clk_sys,
  323. .get_rate = local_return_parent_rate,
  324. };
  325. /*
  326. * Setup the USB PLL with a PLL structure
  327. */
  328. static u32 local_clk_usbpll_setup(struct clk_pll_setup *pHCLKPllSetup)
  329. {
  330. u32 reg, tmp = local_clk_pll_setup(pHCLKPllSetup);
  331. reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL) & ~0x1FFFF;
  332. reg |= tmp;
  333. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  334. return clk_check_pll_setup(clk_usbpll.parent->rate,
  335. pHCLKPllSetup);
  336. }
  337. static int local_usbpll_enable(struct clk *clk, int enable)
  338. {
  339. u32 reg;
  340. int ret = -ENODEV;
  341. unsigned long timeout = 1 + msecs_to_jiffies(10);
  342. reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
  343. if (enable == 0) {
  344. reg &= ~(LPC32XX_CLKPWR_USBCTRL_CLK_EN1 |
  345. LPC32XX_CLKPWR_USBCTRL_CLK_EN2);
  346. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  347. } else if (reg & LPC32XX_CLKPWR_USBCTRL_PLL_PWRUP) {
  348. reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN1;
  349. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  350. /* Wait for PLL lock */
  351. while ((timeout > jiffies) & (ret == -ENODEV)) {
  352. reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
  353. if (reg & LPC32XX_CLKPWR_USBCTRL_PLL_STS)
  354. ret = 0;
  355. }
  356. if (ret == 0) {
  357. reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN2;
  358. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  359. }
  360. }
  361. return ret;
  362. }
  363. static unsigned long local_usbpll_round_rate(struct clk *clk,
  364. unsigned long rate)
  365. {
  366. u32 clkin, usbdiv;
  367. struct clk_pll_setup pllsetup;
  368. /*
  369. * Unlike other clocks, this clock has a KHz input rate, so bump
  370. * it up to work with the PLL function
  371. */
  372. rate = rate * 1000;
  373. clkin = clk->parent->rate;
  374. usbdiv = (__raw_readl(LPC32XX_CLKPWR_USBCLK_PDIV) &
  375. LPC32XX_CLKPWR_USBPDIV_PLL_MASK) + 1;
  376. clkin = clkin / usbdiv;
  377. /* Try to find a good rate setup */
  378. if (local_clk_find_pll_cfg(clkin, rate, &pllsetup) == 0)
  379. return 0;
  380. return clk_check_pll_setup(clkin, &pllsetup);
  381. }
  382. static int local_usbpll_set_rate(struct clk *clk, unsigned long rate)
  383. {
  384. u32 clkin, reg, usbdiv;
  385. struct clk_pll_setup pllsetup;
  386. /*
  387. * Unlike other clocks, this clock has a KHz input rate, so bump
  388. * it up to work with the PLL function
  389. */
  390. rate = rate * 1000;
  391. clkin = clk->get_rate(clk);
  392. usbdiv = (__raw_readl(LPC32XX_CLKPWR_USBCLK_PDIV) &
  393. LPC32XX_CLKPWR_USBPDIV_PLL_MASK) + 1;
  394. clkin = clkin / usbdiv;
  395. /* Try to find a good rate setup */
  396. if (local_clk_find_pll_cfg(clkin, rate, &pllsetup) == 0)
  397. return -EINVAL;
  398. local_usbpll_enable(clk, 0);
  399. reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
  400. reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN1;
  401. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  402. pllsetup.analog_on = 1;
  403. local_clk_usbpll_setup(&pllsetup);
  404. clk->rate = clk_check_pll_setup(clkin, &pllsetup);
  405. reg = __raw_readl(LPC32XX_CLKPWR_USB_CTRL);
  406. reg |= LPC32XX_CLKPWR_USBCTRL_CLK_EN2;
  407. __raw_writel(reg, LPC32XX_CLKPWR_USB_CTRL);
  408. return 0;
  409. }
  410. static struct clk clk_usbpll = {
  411. .parent = &osc_main,
  412. .set_rate = local_usbpll_set_rate,
  413. .enable = local_usbpll_enable,
  414. .rate = 48000, /* In KHz */
  415. .get_rate = local_return_parent_rate,
  416. .round_rate = local_usbpll_round_rate,
  417. };
  418. static u32 clk_get_hclk_div(void)
  419. {
  420. static const u32 hclkdivs[4] = {1, 2, 4, 4};
  421. return hclkdivs[LPC32XX_CLKPWR_HCLKDIV_DIV_2POW(
  422. __raw_readl(LPC32XX_CLKPWR_HCLK_DIV))];
  423. }
  424. static struct clk clk_hclk = {
  425. .parent = &clk_armpll,
  426. .get_rate = local_return_parent_rate,
  427. };
  428. static struct clk clk_pclk = {
  429. .parent = &clk_armpll,
  430. .get_rate = local_return_parent_rate,
  431. };
  432. static int local_onoff_enable(struct clk *clk, int enable)
  433. {
  434. u32 tmp;
  435. tmp = __raw_readl(clk->enable_reg);
  436. if (enable == 0)
  437. tmp &= ~clk->enable_mask;
  438. else
  439. tmp |= clk->enable_mask;
  440. __raw_writel(tmp, clk->enable_reg);
  441. return 0;
  442. }
  443. /* Peripheral clock sources */
  444. static struct clk clk_timer0 = {
  445. .parent = &clk_pclk,
  446. .enable = local_onoff_enable,
  447. .enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
  448. .enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER0_EN,
  449. .get_rate = local_return_parent_rate,
  450. };
  451. static struct clk clk_timer1 = {
  452. .parent = &clk_pclk,
  453. .enable = local_onoff_enable,
  454. .enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
  455. .enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER1_EN,
  456. .get_rate = local_return_parent_rate,
  457. };
  458. static struct clk clk_timer2 = {
  459. .parent = &clk_pclk,
  460. .enable = local_onoff_enable,
  461. .enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
  462. .enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER2_EN,
  463. .get_rate = local_return_parent_rate,
  464. };
  465. static struct clk clk_timer3 = {
  466. .parent = &clk_pclk,
  467. .enable = local_onoff_enable,
  468. .enable_reg = LPC32XX_CLKPWR_TIMERS_PWMS_CLK_CTRL_1,
  469. .enable_mask = LPC32XX_CLKPWR_TMRPWMCLK_TIMER3_EN,
  470. .get_rate = local_return_parent_rate,
  471. };
  472. static struct clk clk_wdt = {
  473. .parent = &clk_pclk,
  474. .enable = local_onoff_enable,
  475. .enable_reg = LPC32XX_CLKPWR_TIMER_CLK_CTRL,
  476. .enable_mask = LPC32XX_CLKPWR_PWMCLK_WDOG_EN,
  477. .get_rate = local_return_parent_rate,
  478. };
  479. static struct clk clk_vfp9 = {
  480. .parent = &clk_pclk,
  481. .enable = local_onoff_enable,
  482. .enable_reg = LPC32XX_CLKPWR_DEBUG_CTRL,
  483. .enable_mask = LPC32XX_CLKPWR_VFP_CLOCK_ENABLE_BIT,
  484. .get_rate = local_return_parent_rate,
  485. };
  486. static struct clk clk_dma = {
  487. .parent = &clk_hclk,
  488. .enable = local_onoff_enable,
  489. .enable_reg = LPC32XX_CLKPWR_DMA_CLK_CTRL,
  490. .enable_mask = LPC32XX_CLKPWR_DMACLKCTRL_CLK_EN,
  491. .get_rate = local_return_parent_rate,
  492. };
  493. static struct clk clk_uart3 = {
  494. .parent = &clk_pclk,
  495. .enable = local_onoff_enable,
  496. .enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
  497. .enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART3_EN,
  498. .get_rate = local_return_parent_rate,
  499. };
  500. static struct clk clk_uart4 = {
  501. .parent = &clk_pclk,
  502. .enable = local_onoff_enable,
  503. .enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
  504. .enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART4_EN,
  505. .get_rate = local_return_parent_rate,
  506. };
  507. static struct clk clk_uart5 = {
  508. .parent = &clk_pclk,
  509. .enable = local_onoff_enable,
  510. .enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
  511. .enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART5_EN,
  512. .get_rate = local_return_parent_rate,
  513. };
  514. static struct clk clk_uart6 = {
  515. .parent = &clk_pclk,
  516. .enable = local_onoff_enable,
  517. .enable_reg = LPC32XX_CLKPWR_UART_CLK_CTRL,
  518. .enable_mask = LPC32XX_CLKPWR_UARTCLKCTRL_UART6_EN,
  519. .get_rate = local_return_parent_rate,
  520. };
  521. static struct clk clk_i2c0 = {
  522. .parent = &clk_hclk,
  523. .enable = local_onoff_enable,
  524. .enable_reg = LPC32XX_CLKPWR_I2C_CLK_CTRL,
  525. .enable_mask = LPC32XX_CLKPWR_I2CCLK_I2C1CLK_EN,
  526. .get_rate = local_return_parent_rate,
  527. };
  528. static struct clk clk_i2c1 = {
  529. .parent = &clk_hclk,
  530. .enable = local_onoff_enable,
  531. .enable_reg = LPC32XX_CLKPWR_I2C_CLK_CTRL,
  532. .enable_mask = LPC32XX_CLKPWR_I2CCLK_I2C2CLK_EN,
  533. .get_rate = local_return_parent_rate,
  534. };
  535. static struct clk clk_i2c2 = {
  536. .parent = &clk_pclk,
  537. .enable = local_onoff_enable,
  538. .enable_reg = io_p2v(LPC32XX_USB_BASE + 0xFF4),
  539. .enable_mask = 0x4,
  540. .get_rate = local_return_parent_rate,
  541. };
  542. static struct clk clk_ssp0 = {
  543. .parent = &clk_hclk,
  544. .enable = local_onoff_enable,
  545. .enable_reg = LPC32XX_CLKPWR_SSP_CLK_CTRL,
  546. .enable_mask = LPC32XX_CLKPWR_SSPCTRL_SSPCLK0_EN,
  547. .get_rate = local_return_parent_rate,
  548. };
  549. static struct clk clk_ssp1 = {
  550. .parent = &clk_hclk,
  551. .enable = local_onoff_enable,
  552. .enable_reg = LPC32XX_CLKPWR_SSP_CLK_CTRL,
  553. .enable_mask = LPC32XX_CLKPWR_SSPCTRL_SSPCLK1_EN,
  554. .get_rate = local_return_parent_rate,
  555. };
  556. static struct clk clk_kscan = {
  557. .parent = &osc_32KHz,
  558. .enable = local_onoff_enable,
  559. .enable_reg = LPC32XX_CLKPWR_KEY_CLK_CTRL,
  560. .enable_mask = LPC32XX_CLKPWR_KEYCLKCTRL_CLK_EN,
  561. .get_rate = local_return_parent_rate,
  562. };
  563. static struct clk clk_nand = {
  564. .parent = &clk_hclk,
  565. .enable = local_onoff_enable,
  566. .enable_reg = LPC32XX_CLKPWR_NAND_CLK_CTRL,
  567. .enable_mask = LPC32XX_CLKPWR_NANDCLK_SLCCLK_EN,
  568. .get_rate = local_return_parent_rate,
  569. };
  570. static struct clk clk_i2s0 = {
  571. .parent = &clk_hclk,
  572. .enable = local_onoff_enable,
  573. .enable_reg = LPC32XX_CLKPWR_I2S_CLK_CTRL,
  574. .enable_mask = LPC32XX_CLKPWR_I2SCTRL_I2SCLK0_EN,
  575. .get_rate = local_return_parent_rate,
  576. };
  577. static struct clk clk_i2s1 = {
  578. .parent = &clk_hclk,
  579. .enable = local_onoff_enable,
  580. .enable_reg = LPC32XX_CLKPWR_I2S_CLK_CTRL,
  581. .enable_mask = LPC32XX_CLKPWR_I2SCTRL_I2SCLK1_EN,
  582. .get_rate = local_return_parent_rate,
  583. };
  584. static struct clk clk_net = {
  585. .parent = &clk_hclk,
  586. .enable = local_onoff_enable,
  587. .enable_reg = LPC32XX_CLKPWR_MACCLK_CTRL,
  588. .enable_mask = (LPC32XX_CLKPWR_MACCTRL_DMACLK_EN |
  589. LPC32XX_CLKPWR_MACCTRL_MMIOCLK_EN |
  590. LPC32XX_CLKPWR_MACCTRL_HRCCLK_EN),
  591. .get_rate = local_return_parent_rate,
  592. };
  593. static struct clk clk_rtc = {
  594. .parent = &osc_32KHz,
  595. .rate = 1, /* 1 Hz */
  596. .get_rate = local_return_parent_rate,
  597. };
  598. static struct clk clk_usbd = {
  599. .parent = &clk_usbpll,
  600. .enable = local_onoff_enable,
  601. .enable_reg = LPC32XX_CLKPWR_USB_CTRL,
  602. .enable_mask = LPC32XX_CLKPWR_USBCTRL_HCLK_EN,
  603. .get_rate = local_return_parent_rate,
  604. };
  605. static int tsc_onoff_enable(struct clk *clk, int enable)
  606. {
  607. u32 tmp;
  608. /* Make sure 32KHz clock is the selected clock */
  609. tmp = __raw_readl(LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
  610. tmp &= ~LPC32XX_CLKPWR_ADCCTRL1_PCLK_SEL;
  611. __raw_writel(tmp, LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
  612. if (enable == 0)
  613. __raw_writel(0, clk->enable_reg);
  614. else
  615. __raw_writel(clk->enable_mask, clk->enable_reg);
  616. return 0;
  617. }
  618. static struct clk clk_tsc = {
  619. .parent = &osc_32KHz,
  620. .enable = tsc_onoff_enable,
  621. .enable_reg = LPC32XX_CLKPWR_ADC_CLK_CTRL,
  622. .enable_mask = LPC32XX_CLKPWR_ADC32CLKCTRL_CLK_EN,
  623. .get_rate = local_return_parent_rate,
  624. };
  625. static int mmc_onoff_enable(struct clk *clk, int enable)
  626. {
  627. u32 tmp;
  628. tmp = __raw_readl(LPC32XX_CLKPWR_MS_CTRL) &
  629. ~LPC32XX_CLKPWR_MSCARD_SDCARD_EN;
  630. /* If rate is 0, disable clock */
  631. if (enable != 0)
  632. tmp |= LPC32XX_CLKPWR_MSCARD_SDCARD_EN;
  633. __raw_writel(tmp, LPC32XX_CLKPWR_MS_CTRL);
  634. return 0;
  635. }
  636. static unsigned long mmc_get_rate(struct clk *clk)
  637. {
  638. u32 div, rate, oldclk;
  639. /* The MMC clock must be on when accessing an MMC register */
  640. oldclk = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
  641. __raw_writel(oldclk | LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
  642. LPC32XX_CLKPWR_MS_CTRL);
  643. div = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
  644. __raw_writel(oldclk, LPC32XX_CLKPWR_MS_CTRL);
  645. /* Get the parent clock rate */
  646. rate = clk->parent->get_rate(clk->parent);
  647. /* Get the MMC controller clock divider value */
  648. div = div & LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(0xf);
  649. if (!div)
  650. div = 1;
  651. return rate / div;
  652. }
  653. static unsigned long mmc_round_rate(struct clk *clk, unsigned long rate)
  654. {
  655. unsigned long div, prate;
  656. /* Get the parent clock rate */
  657. prate = clk->parent->get_rate(clk->parent);
  658. if (rate >= prate)
  659. return prate;
  660. div = prate / rate;
  661. if (div > 0xf)
  662. div = 0xf;
  663. return prate / div;
  664. }
  665. static int mmc_set_rate(struct clk *clk, unsigned long rate)
  666. {
  667. u32 oldclk, tmp;
  668. unsigned long prate, div, crate = mmc_round_rate(clk, rate);
  669. prate = clk->parent->get_rate(clk->parent);
  670. div = prate / crate;
  671. /* The MMC clock must be on when accessing an MMC register */
  672. oldclk = __raw_readl(LPC32XX_CLKPWR_MS_CTRL);
  673. __raw_writel(oldclk | LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
  674. LPC32XX_CLKPWR_MS_CTRL);
  675. tmp = __raw_readl(LPC32XX_CLKPWR_MS_CTRL) &
  676. ~LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(0xf);
  677. tmp |= LPC32XX_CLKPWR_MSCARD_SDCARD_DIV(div);
  678. __raw_writel(tmp, LPC32XX_CLKPWR_MS_CTRL);
  679. __raw_writel(oldclk, LPC32XX_CLKPWR_MS_CTRL);
  680. return 0;
  681. }
  682. static struct clk clk_mmc = {
  683. .parent = &clk_armpll,
  684. .set_rate = mmc_set_rate,
  685. .get_rate = mmc_get_rate,
  686. .round_rate = mmc_round_rate,
  687. .enable = mmc_onoff_enable,
  688. .enable_reg = LPC32XX_CLKPWR_MS_CTRL,
  689. .enable_mask = LPC32XX_CLKPWR_MSCARD_SDCARD_EN,
  690. };
  691. static unsigned long clcd_get_rate(struct clk *clk)
  692. {
  693. u32 tmp, div, rate, oldclk;
  694. /* The LCD clock must be on when accessing an LCD register */
  695. oldclk = __raw_readl(LPC32XX_CLKPWR_LCDCLK_CTRL);
  696. __raw_writel(oldclk | LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
  697. LPC32XX_CLKPWR_LCDCLK_CTRL);
  698. tmp = __raw_readl(io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2));
  699. __raw_writel(oldclk, LPC32XX_CLKPWR_LCDCLK_CTRL);
  700. rate = clk->parent->get_rate(clk->parent);
  701. /* Only supports internal clocking */
  702. if (tmp & TIM2_BCD)
  703. return rate;
  704. div = (tmp & 0x1F) | ((tmp & 0xF8) >> 22);
  705. tmp = rate / (2 + div);
  706. return tmp;
  707. }
  708. static int clcd_set_rate(struct clk *clk, unsigned long rate)
  709. {
  710. u32 tmp, prate, div, oldclk;
  711. /* The LCD clock must be on when accessing an LCD register */
  712. oldclk = __raw_readl(LPC32XX_CLKPWR_LCDCLK_CTRL);
  713. __raw_writel(oldclk | LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
  714. LPC32XX_CLKPWR_LCDCLK_CTRL);
  715. tmp = __raw_readl(io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2)) | TIM2_BCD;
  716. prate = clk->parent->get_rate(clk->parent);
  717. if (rate < prate) {
  718. /* Find closest divider */
  719. div = prate / rate;
  720. if (div >= 2) {
  721. div -= 2;
  722. tmp &= ~TIM2_BCD;
  723. }
  724. tmp &= ~(0xF800001F);
  725. tmp |= (div & 0x1F);
  726. tmp |= (((div >> 5) & 0x1F) << 27);
  727. }
  728. __raw_writel(tmp, io_p2v(LPC32XX_LCD_BASE + CLCD_TIM2));
  729. __raw_writel(oldclk, LPC32XX_CLKPWR_LCDCLK_CTRL);
  730. return 0;
  731. }
  732. static unsigned long clcd_round_rate(struct clk *clk, unsigned long rate)
  733. {
  734. u32 prate, div;
  735. prate = clk->parent->get_rate(clk->parent);
  736. if (rate >= prate)
  737. rate = prate;
  738. else {
  739. div = prate / rate;
  740. if (div > 0x3ff)
  741. div = 0x3ff;
  742. rate = prate / div;
  743. }
  744. return rate;
  745. }
  746. static struct clk clk_lcd = {
  747. .parent = &clk_hclk,
  748. .set_rate = clcd_set_rate,
  749. .get_rate = clcd_get_rate,
  750. .round_rate = clcd_round_rate,
  751. .enable = local_onoff_enable,
  752. .enable_reg = LPC32XX_CLKPWR_LCDCLK_CTRL,
  753. .enable_mask = LPC32XX_CLKPWR_LCDCTRL_CLK_EN,
  754. };
  755. static inline void clk_lock(void)
  756. {
  757. mutex_lock(&clkm_lock);
  758. }
  759. static inline void clk_unlock(void)
  760. {
  761. mutex_unlock(&clkm_lock);
  762. }
  763. static void local_clk_disable(struct clk *clk)
  764. {
  765. WARN_ON(clk->usecount == 0);
  766. /* Don't attempt to disable clock if it has no users */
  767. if (clk->usecount > 0) {
  768. clk->usecount--;
  769. /* Only disable clock when it has no more users */
  770. if ((clk->usecount == 0) && (clk->enable))
  771. clk->enable(clk, 0);
  772. /* Check parent clocks, they may need to be disabled too */
  773. if (clk->parent)
  774. local_clk_disable(clk->parent);
  775. }
  776. }
  777. static int local_clk_enable(struct clk *clk)
  778. {
  779. int ret = 0;
  780. /* Enable parent clocks first and update use counts */
  781. if (clk->parent)
  782. ret = local_clk_enable(clk->parent);
  783. if (!ret) {
  784. /* Only enable clock if it's currently disabled */
  785. if ((clk->usecount == 0) && (clk->enable))
  786. ret = clk->enable(clk, 1);
  787. if (!ret)
  788. clk->usecount++;
  789. else if (clk->parent)
  790. local_clk_disable(clk->parent);
  791. }
  792. return ret;
  793. }
  794. /*
  795. * clk_enable - inform the system when the clock source should be running.
  796. */
  797. int clk_enable(struct clk *clk)
  798. {
  799. int ret;
  800. clk_lock();
  801. ret = local_clk_enable(clk);
  802. clk_unlock();
  803. return ret;
  804. }
  805. EXPORT_SYMBOL(clk_enable);
  806. /*
  807. * clk_disable - inform the system when the clock source is no longer required
  808. */
  809. void clk_disable(struct clk *clk)
  810. {
  811. clk_lock();
  812. local_clk_disable(clk);
  813. clk_unlock();
  814. }
  815. EXPORT_SYMBOL(clk_disable);
  816. /*
  817. * clk_get_rate - obtain the current clock rate (in Hz) for a clock source
  818. */
  819. unsigned long clk_get_rate(struct clk *clk)
  820. {
  821. unsigned long rate;
  822. clk_lock();
  823. rate = clk->get_rate(clk);
  824. clk_unlock();
  825. return rate;
  826. }
  827. EXPORT_SYMBOL(clk_get_rate);
  828. /*
  829. * clk_set_rate - set the clock rate for a clock source
  830. */
  831. int clk_set_rate(struct clk *clk, unsigned long rate)
  832. {
  833. int ret = -EINVAL;
  834. /*
  835. * Most system clocks can only be enabled or disabled, with
  836. * the actual rate set as part of the peripheral dividers
  837. * instead of high level clock control
  838. */
  839. if (clk->set_rate) {
  840. clk_lock();
  841. ret = clk->set_rate(clk, rate);
  842. clk_unlock();
  843. }
  844. return ret;
  845. }
  846. EXPORT_SYMBOL(clk_set_rate);
  847. /*
  848. * clk_round_rate - adjust a rate to the exact rate a clock can provide
  849. */
  850. long clk_round_rate(struct clk *clk, unsigned long rate)
  851. {
  852. clk_lock();
  853. if (clk->round_rate)
  854. rate = clk->round_rate(clk, rate);
  855. else
  856. rate = clk->get_rate(clk);
  857. clk_unlock();
  858. return rate;
  859. }
  860. EXPORT_SYMBOL(clk_round_rate);
  861. /*
  862. * clk_set_parent - set the parent clock source for this clock
  863. */
  864. int clk_set_parent(struct clk *clk, struct clk *parent)
  865. {
  866. /* Clock re-parenting is not supported */
  867. return -EINVAL;
  868. }
  869. EXPORT_SYMBOL(clk_set_parent);
  870. /*
  871. * clk_get_parent - get the parent clock source for this clock
  872. */
  873. struct clk *clk_get_parent(struct clk *clk)
  874. {
  875. return clk->parent;
  876. }
  877. EXPORT_SYMBOL(clk_get_parent);
  878. #define _REGISTER_CLOCK(d, n, c) \
  879. { \
  880. .dev_id = (d), \
  881. .con_id = (n), \
  882. .clk = &(c), \
  883. },
  884. static struct clk_lookup lookups[] = {
  885. _REGISTER_CLOCK(NULL, "osc_32KHz", osc_32KHz)
  886. _REGISTER_CLOCK(NULL, "osc_pll397", osc_pll397)
  887. _REGISTER_CLOCK(NULL, "osc_main", osc_main)
  888. _REGISTER_CLOCK(NULL, "sys_ck", clk_sys)
  889. _REGISTER_CLOCK(NULL, "arm_pll_ck", clk_armpll)
  890. _REGISTER_CLOCK(NULL, "ck_pll5", clk_usbpll)
  891. _REGISTER_CLOCK(NULL, "hclk_ck", clk_hclk)
  892. _REGISTER_CLOCK(NULL, "pclk_ck", clk_pclk)
  893. _REGISTER_CLOCK(NULL, "timer0_ck", clk_timer0)
  894. _REGISTER_CLOCK(NULL, "timer1_ck", clk_timer1)
  895. _REGISTER_CLOCK(NULL, "timer2_ck", clk_timer2)
  896. _REGISTER_CLOCK(NULL, "timer3_ck", clk_timer3)
  897. _REGISTER_CLOCK(NULL, "vfp9_ck", clk_vfp9)
  898. _REGISTER_CLOCK(NULL, "clk_dmac", clk_dma)
  899. _REGISTER_CLOCK("pnx4008-watchdog", NULL, clk_wdt)
  900. _REGISTER_CLOCK(NULL, "uart3_ck", clk_uart3)
  901. _REGISTER_CLOCK(NULL, "uart4_ck", clk_uart4)
  902. _REGISTER_CLOCK(NULL, "uart5_ck", clk_uart5)
  903. _REGISTER_CLOCK(NULL, "uart6_ck", clk_uart6)
  904. _REGISTER_CLOCK("pnx-i2c.0", NULL, clk_i2c0)
  905. _REGISTER_CLOCK("pnx-i2c.1", NULL, clk_i2c1)
  906. _REGISTER_CLOCK("pnx-i2c.2", NULL, clk_i2c2)
  907. _REGISTER_CLOCK("dev:ssp0", NULL, clk_ssp0)
  908. _REGISTER_CLOCK("dev:ssp1", NULL, clk_ssp1)
  909. _REGISTER_CLOCK("lpc32xx_keys.0", NULL, clk_kscan)
  910. _REGISTER_CLOCK("lpc32xx-nand.0", "nand_ck", clk_nand)
  911. _REGISTER_CLOCK("tbd", "i2s0_ck", clk_i2s0)
  912. _REGISTER_CLOCK("tbd", "i2s1_ck", clk_i2s1)
  913. _REGISTER_CLOCK("lpc32xx-ts", NULL, clk_tsc)
  914. _REGISTER_CLOCK("dev:mmc0", "MCLK", clk_mmc)
  915. _REGISTER_CLOCK("lpc-net.0", NULL, clk_net)
  916. _REGISTER_CLOCK("dev:clcd", NULL, clk_lcd)
  917. _REGISTER_CLOCK("lpc32xx_udc", "ck_usbd", clk_usbd)
  918. _REGISTER_CLOCK("lpc32xx_rtc", NULL, clk_rtc)
  919. };
  920. static int __init clk_init(void)
  921. {
  922. int i;
  923. for (i = 0; i < ARRAY_SIZE(lookups); i++)
  924. clkdev_add(&lookups[i]);
  925. /*
  926. * Setup muxed SYSCLK for HCLK PLL base -this selects the
  927. * parent clock used for the ARM PLL and is used to derive
  928. * the many system clock rates in the device.
  929. */
  930. if (clk_is_sysclk_mainosc() != 0)
  931. clk_sys.parent = &osc_main;
  932. else
  933. clk_sys.parent = &osc_pll397;
  934. clk_sys.rate = clk_sys.parent->rate;
  935. /* Compute the current ARM PLL and USB PLL frequencies */
  936. local_update_armpll_rate();
  937. /* Compute HCLK and PCLK bus rates */
  938. clk_hclk.rate = clk_hclk.parent->rate / clk_get_hclk_div();
  939. clk_pclk.rate = clk_pclk.parent->rate / clk_get_pclk_div();
  940. /*
  941. * Enable system clocks - this step is somewhat formal, as the
  942. * clocks are already running, but it does get the clock data
  943. * inline with the actual system state. Never disable these
  944. * clocks as they will only stop if the system is going to sleep.
  945. * In that case, the chip/system power management functions will
  946. * handle clock gating.
  947. */
  948. if (clk_enable(&clk_hclk) || clk_enable(&clk_pclk))
  949. printk(KERN_ERR "Error enabling system HCLK and PCLK\n");
  950. /*
  951. * Timers 0 and 1 were enabled and are being used by the high
  952. * resolution tick function prior to this driver being initialized.
  953. * Tag them now as used.
  954. */
  955. if (clk_enable(&clk_timer0) || clk_enable(&clk_timer1))
  956. printk(KERN_ERR "Error enabling timer tick clocks\n");
  957. return 0;
  958. }
  959. core_initcall(clk_init);