clk-xgene.c 19 KB

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  1. /*
  2. * clk-xgene.c - AppliedMicro X-Gene Clock Interface
  3. *
  4. * Copyright (c) 2013, Applied Micro Circuits Corporation
  5. * Author: Loc Ho <lho@apm.com>
  6. *
  7. * This program is free software; you can redistribute it and/or
  8. * modify it under the terms of the GNU General Public License as
  9. * published by the Free Software Foundation; either version 2 of
  10. * the License, or (at your option) any later version.
  11. *
  12. * This program is distributed in the hope that it will be useful,
  13. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15. * GNU General Public License for more details.
  16. *
  17. * You should have received a copy of the GNU General Public License
  18. * along with this program; if not, write to the Free Software
  19. * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  20. * MA 02111-1307 USA
  21. *
  22. */
  23. #include <linux/module.h>
  24. #include <linux/spinlock.h>
  25. #include <linux/io.h>
  26. #include <linux/of.h>
  27. #include <linux/clkdev.h>
  28. #include <linux/clk-provider.h>
  29. #include <linux/of_address.h>
  30. /* Register SCU_PCPPLL bit fields */
  31. #define N_DIV_RD(src) ((src) & 0x000001ff)
  32. #define SC_N_DIV_RD(src) ((src) & 0x0000007f)
  33. #define SC_OUTDIV2(src) (((src) & 0x00000100) >> 8)
  34. /* Register SCU_SOCPLL bit fields */
  35. #define CLKR_RD(src) (((src) & 0x07000000)>>24)
  36. #define CLKOD_RD(src) (((src) & 0x00300000)>>20)
  37. #define REGSPEC_RESET_F1_MASK 0x00010000
  38. #define CLKF_RD(src) (((src) & 0x000001ff))
  39. #define XGENE_CLK_DRIVER_VER "0.1"
  40. static DEFINE_SPINLOCK(clk_lock);
  41. static inline u32 xgene_clk_read(void __iomem *csr)
  42. {
  43. return readl_relaxed(csr);
  44. }
  45. static inline void xgene_clk_write(u32 data, void __iomem *csr)
  46. {
  47. writel_relaxed(data, csr);
  48. }
  49. /* PLL Clock */
  50. enum xgene_pll_type {
  51. PLL_TYPE_PCP = 0,
  52. PLL_TYPE_SOC = 1,
  53. };
  54. struct xgene_clk_pll {
  55. struct clk_hw hw;
  56. void __iomem *reg;
  57. spinlock_t *lock;
  58. u32 pll_offset;
  59. enum xgene_pll_type type;
  60. int version;
  61. };
  62. #define to_xgene_clk_pll(_hw) container_of(_hw, struct xgene_clk_pll, hw)
  63. static int xgene_clk_pll_is_enabled(struct clk_hw *hw)
  64. {
  65. struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
  66. u32 data;
  67. data = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
  68. pr_debug("%s pll %s\n", clk_hw_get_name(hw),
  69. data & REGSPEC_RESET_F1_MASK ? "disabled" : "enabled");
  70. return data & REGSPEC_RESET_F1_MASK ? 0 : 1;
  71. }
  72. static unsigned long xgene_clk_pll_recalc_rate(struct clk_hw *hw,
  73. unsigned long parent_rate)
  74. {
  75. struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
  76. unsigned long fref;
  77. unsigned long fvco;
  78. u32 pll;
  79. u32 nref;
  80. u32 nout;
  81. u32 nfb;
  82. pll = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
  83. if (pllclk->version <= 1) {
  84. if (pllclk->type == PLL_TYPE_PCP) {
  85. /*
  86. * PLL VCO = Reference clock * NF
  87. * PCP PLL = PLL_VCO / 2
  88. */
  89. nout = 2;
  90. fvco = parent_rate * (N_DIV_RD(pll) + 4);
  91. } else {
  92. /*
  93. * Fref = Reference Clock / NREF;
  94. * Fvco = Fref * NFB;
  95. * Fout = Fvco / NOUT;
  96. */
  97. nref = CLKR_RD(pll) + 1;
  98. nout = CLKOD_RD(pll) + 1;
  99. nfb = CLKF_RD(pll);
  100. fref = parent_rate / nref;
  101. fvco = fref * nfb;
  102. }
  103. } else {
  104. /*
  105. * fvco = Reference clock * FBDIVC
  106. * PLL freq = fvco / NOUT
  107. */
  108. nout = SC_OUTDIV2(pll) ? 2 : 3;
  109. fvco = parent_rate * SC_N_DIV_RD(pll);
  110. }
  111. pr_debug("%s pll recalc rate %ld parent %ld version %d\n",
  112. clk_hw_get_name(hw), fvco / nout, parent_rate,
  113. pllclk->version);
  114. return fvco / nout;
  115. }
  116. static const struct clk_ops xgene_clk_pll_ops = {
  117. .is_enabled = xgene_clk_pll_is_enabled,
  118. .recalc_rate = xgene_clk_pll_recalc_rate,
  119. };
  120. static struct clk *xgene_register_clk_pll(struct device *dev,
  121. const char *name, const char *parent_name,
  122. unsigned long flags, void __iomem *reg, u32 pll_offset,
  123. u32 type, spinlock_t *lock, int version)
  124. {
  125. struct xgene_clk_pll *apmclk;
  126. struct clk *clk;
  127. struct clk_init_data init;
  128. /* allocate the APM clock structure */
  129. apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
  130. if (!apmclk)
  131. return ERR_PTR(-ENOMEM);
  132. init.name = name;
  133. init.ops = &xgene_clk_pll_ops;
  134. init.flags = flags;
  135. init.parent_names = parent_name ? &parent_name : NULL;
  136. init.num_parents = parent_name ? 1 : 0;
  137. apmclk->version = version;
  138. apmclk->reg = reg;
  139. apmclk->lock = lock;
  140. apmclk->pll_offset = pll_offset;
  141. apmclk->type = type;
  142. apmclk->hw.init = &init;
  143. /* Register the clock */
  144. clk = clk_register(dev, &apmclk->hw);
  145. if (IS_ERR(clk)) {
  146. pr_err("%s: could not register clk %s\n", __func__, name);
  147. kfree(apmclk);
  148. return NULL;
  149. }
  150. return clk;
  151. }
  152. static int xgene_pllclk_version(struct device_node *np)
  153. {
  154. if (of_device_is_compatible(np, "apm,xgene-socpll-clock"))
  155. return 1;
  156. if (of_device_is_compatible(np, "apm,xgene-pcppll-clock"))
  157. return 1;
  158. return 2;
  159. }
  160. static void xgene_pllclk_init(struct device_node *np, enum xgene_pll_type pll_type)
  161. {
  162. const char *clk_name = np->full_name;
  163. struct clk *clk;
  164. void __iomem *reg;
  165. int version = xgene_pllclk_version(np);
  166. reg = of_iomap(np, 0);
  167. if (!reg) {
  168. pr_err("Unable to map CSR register for %pOF\n", np);
  169. return;
  170. }
  171. of_property_read_string(np, "clock-output-names", &clk_name);
  172. clk = xgene_register_clk_pll(NULL,
  173. clk_name, of_clk_get_parent_name(np, 0),
  174. 0, reg, 0, pll_type, &clk_lock,
  175. version);
  176. if (!IS_ERR(clk)) {
  177. of_clk_add_provider(np, of_clk_src_simple_get, clk);
  178. clk_register_clkdev(clk, clk_name, NULL);
  179. pr_debug("Add %s clock PLL\n", clk_name);
  180. }
  181. }
  182. static void xgene_socpllclk_init(struct device_node *np)
  183. {
  184. xgene_pllclk_init(np, PLL_TYPE_SOC);
  185. }
  186. static void xgene_pcppllclk_init(struct device_node *np)
  187. {
  188. xgene_pllclk_init(np, PLL_TYPE_PCP);
  189. }
  190. /**
  191. * struct xgene_clk_pmd - PMD clock
  192. *
  193. * @hw: handle between common and hardware-specific interfaces
  194. * @reg: register containing the fractional scale multiplier (scaler)
  195. * @shift: shift to the unit bit field
  196. * @denom: 1/denominator unit
  197. * @lock: register lock
  198. * Flags:
  199. * XGENE_CLK_PMD_SCALE_INVERTED - By default the scaler is the value read
  200. * from the register plus one. For example,
  201. * 0 for (0 + 1) / denom,
  202. * 1 for (1 + 1) / denom and etc.
  203. * If this flag is set, it is
  204. * 0 for (denom - 0) / denom,
  205. * 1 for (denom - 1) / denom and etc.
  206. *
  207. */
  208. struct xgene_clk_pmd {
  209. struct clk_hw hw;
  210. void __iomem *reg;
  211. u8 shift;
  212. u32 mask;
  213. u64 denom;
  214. u32 flags;
  215. spinlock_t *lock;
  216. };
  217. #define to_xgene_clk_pmd(_hw) container_of(_hw, struct xgene_clk_pmd, hw)
  218. #define XGENE_CLK_PMD_SCALE_INVERTED BIT(0)
  219. #define XGENE_CLK_PMD_SHIFT 8
  220. #define XGENE_CLK_PMD_WIDTH 3
  221. static unsigned long xgene_clk_pmd_recalc_rate(struct clk_hw *hw,
  222. unsigned long parent_rate)
  223. {
  224. struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
  225. unsigned long flags = 0;
  226. u64 ret, scale;
  227. u32 val;
  228. if (fd->lock)
  229. spin_lock_irqsave(fd->lock, flags);
  230. else
  231. __acquire(fd->lock);
  232. val = clk_readl(fd->reg);
  233. if (fd->lock)
  234. spin_unlock_irqrestore(fd->lock, flags);
  235. else
  236. __release(fd->lock);
  237. ret = (u64)parent_rate;
  238. scale = (val & fd->mask) >> fd->shift;
  239. if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
  240. scale = fd->denom - scale;
  241. else
  242. scale++;
  243. /* freq = parent_rate * scaler / denom */
  244. do_div(ret, fd->denom);
  245. ret *= scale;
  246. if (ret == 0)
  247. ret = (u64)parent_rate;
  248. return ret;
  249. }
  250. static long xgene_clk_pmd_round_rate(struct clk_hw *hw, unsigned long rate,
  251. unsigned long *parent_rate)
  252. {
  253. struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
  254. u64 ret, scale;
  255. if (!rate || rate >= *parent_rate)
  256. return *parent_rate;
  257. /* freq = parent_rate * scaler / denom */
  258. ret = rate * fd->denom;
  259. scale = DIV_ROUND_UP_ULL(ret, *parent_rate);
  260. ret = (u64)*parent_rate * scale;
  261. do_div(ret, fd->denom);
  262. return ret;
  263. }
  264. static int xgene_clk_pmd_set_rate(struct clk_hw *hw, unsigned long rate,
  265. unsigned long parent_rate)
  266. {
  267. struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
  268. unsigned long flags = 0;
  269. u64 scale, ret;
  270. u32 val;
  271. /*
  272. * Compute the scaler:
  273. *
  274. * freq = parent_rate * scaler / denom, or
  275. * scaler = freq * denom / parent_rate
  276. */
  277. ret = rate * fd->denom;
  278. scale = DIV_ROUND_UP_ULL(ret, (u64)parent_rate);
  279. /* Check if inverted */
  280. if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
  281. scale = fd->denom - scale;
  282. else
  283. scale--;
  284. if (fd->lock)
  285. spin_lock_irqsave(fd->lock, flags);
  286. else
  287. __acquire(fd->lock);
  288. val = clk_readl(fd->reg);
  289. val &= ~fd->mask;
  290. val |= (scale << fd->shift);
  291. clk_writel(val, fd->reg);
  292. if (fd->lock)
  293. spin_unlock_irqrestore(fd->lock, flags);
  294. else
  295. __release(fd->lock);
  296. return 0;
  297. }
  298. static const struct clk_ops xgene_clk_pmd_ops = {
  299. .recalc_rate = xgene_clk_pmd_recalc_rate,
  300. .round_rate = xgene_clk_pmd_round_rate,
  301. .set_rate = xgene_clk_pmd_set_rate,
  302. };
  303. static struct clk *
  304. xgene_register_clk_pmd(struct device *dev,
  305. const char *name, const char *parent_name,
  306. unsigned long flags, void __iomem *reg, u8 shift,
  307. u8 width, u64 denom, u32 clk_flags, spinlock_t *lock)
  308. {
  309. struct xgene_clk_pmd *fd;
  310. struct clk_init_data init;
  311. struct clk *clk;
  312. fd = kzalloc(sizeof(*fd), GFP_KERNEL);
  313. if (!fd)
  314. return ERR_PTR(-ENOMEM);
  315. init.name = name;
  316. init.ops = &xgene_clk_pmd_ops;
  317. init.flags = flags;
  318. init.parent_names = parent_name ? &parent_name : NULL;
  319. init.num_parents = parent_name ? 1 : 0;
  320. fd->reg = reg;
  321. fd->shift = shift;
  322. fd->mask = (BIT(width) - 1) << shift;
  323. fd->denom = denom;
  324. fd->flags = clk_flags;
  325. fd->lock = lock;
  326. fd->hw.init = &init;
  327. clk = clk_register(dev, &fd->hw);
  328. if (IS_ERR(clk)) {
  329. pr_err("%s: could not register clk %s\n", __func__, name);
  330. kfree(fd);
  331. return NULL;
  332. }
  333. return clk;
  334. }
  335. static void xgene_pmdclk_init(struct device_node *np)
  336. {
  337. const char *clk_name = np->full_name;
  338. void __iomem *csr_reg;
  339. struct resource res;
  340. struct clk *clk;
  341. u64 denom;
  342. u32 flags = 0;
  343. int rc;
  344. /* Check if the entry is disabled */
  345. if (!of_device_is_available(np))
  346. return;
  347. /* Parse the DTS register for resource */
  348. rc = of_address_to_resource(np, 0, &res);
  349. if (rc != 0) {
  350. pr_err("no DTS register for %pOF\n", np);
  351. return;
  352. }
  353. csr_reg = of_iomap(np, 0);
  354. if (!csr_reg) {
  355. pr_err("Unable to map resource for %pOF\n", np);
  356. return;
  357. }
  358. of_property_read_string(np, "clock-output-names", &clk_name);
  359. denom = BIT(XGENE_CLK_PMD_WIDTH);
  360. flags |= XGENE_CLK_PMD_SCALE_INVERTED;
  361. clk = xgene_register_clk_pmd(NULL, clk_name,
  362. of_clk_get_parent_name(np, 0), 0,
  363. csr_reg, XGENE_CLK_PMD_SHIFT,
  364. XGENE_CLK_PMD_WIDTH, denom,
  365. flags, &clk_lock);
  366. if (!IS_ERR(clk)) {
  367. of_clk_add_provider(np, of_clk_src_simple_get, clk);
  368. clk_register_clkdev(clk, clk_name, NULL);
  369. pr_debug("Add %s clock\n", clk_name);
  370. } else {
  371. if (csr_reg)
  372. iounmap(csr_reg);
  373. }
  374. }
  375. /* IP Clock */
  376. struct xgene_dev_parameters {
  377. void __iomem *csr_reg; /* CSR for IP clock */
  378. u32 reg_clk_offset; /* Offset to clock enable CSR */
  379. u32 reg_clk_mask; /* Mask bit for clock enable */
  380. u32 reg_csr_offset; /* Offset to CSR reset */
  381. u32 reg_csr_mask; /* Mask bit for disable CSR reset */
  382. void __iomem *divider_reg; /* CSR for divider */
  383. u32 reg_divider_offset; /* Offset to divider register */
  384. u32 reg_divider_shift; /* Bit shift to divider field */
  385. u32 reg_divider_width; /* Width of the bit to divider field */
  386. };
  387. struct xgene_clk {
  388. struct clk_hw hw;
  389. spinlock_t *lock;
  390. struct xgene_dev_parameters param;
  391. };
  392. #define to_xgene_clk(_hw) container_of(_hw, struct xgene_clk, hw)
  393. static int xgene_clk_enable(struct clk_hw *hw)
  394. {
  395. struct xgene_clk *pclk = to_xgene_clk(hw);
  396. unsigned long flags = 0;
  397. u32 data;
  398. if (pclk->lock)
  399. spin_lock_irqsave(pclk->lock, flags);
  400. if (pclk->param.csr_reg) {
  401. pr_debug("%s clock enabled\n", clk_hw_get_name(hw));
  402. /* First enable the clock */
  403. data = xgene_clk_read(pclk->param.csr_reg +
  404. pclk->param.reg_clk_offset);
  405. data |= pclk->param.reg_clk_mask;
  406. xgene_clk_write(data, pclk->param.csr_reg +
  407. pclk->param.reg_clk_offset);
  408. pr_debug("%s clk offset 0x%08X mask 0x%08X value 0x%08X\n",
  409. clk_hw_get_name(hw),
  410. pclk->param.reg_clk_offset, pclk->param.reg_clk_mask,
  411. data);
  412. /* Second enable the CSR */
  413. data = xgene_clk_read(pclk->param.csr_reg +
  414. pclk->param.reg_csr_offset);
  415. data &= ~pclk->param.reg_csr_mask;
  416. xgene_clk_write(data, pclk->param.csr_reg +
  417. pclk->param.reg_csr_offset);
  418. pr_debug("%s csr offset 0x%08X mask 0x%08X value 0x%08X\n",
  419. clk_hw_get_name(hw),
  420. pclk->param.reg_csr_offset, pclk->param.reg_csr_mask,
  421. data);
  422. }
  423. if (pclk->lock)
  424. spin_unlock_irqrestore(pclk->lock, flags);
  425. return 0;
  426. }
  427. static void xgene_clk_disable(struct clk_hw *hw)
  428. {
  429. struct xgene_clk *pclk = to_xgene_clk(hw);
  430. unsigned long flags = 0;
  431. u32 data;
  432. if (pclk->lock)
  433. spin_lock_irqsave(pclk->lock, flags);
  434. if (pclk->param.csr_reg) {
  435. pr_debug("%s clock disabled\n", clk_hw_get_name(hw));
  436. /* First put the CSR in reset */
  437. data = xgene_clk_read(pclk->param.csr_reg +
  438. pclk->param.reg_csr_offset);
  439. data |= pclk->param.reg_csr_mask;
  440. xgene_clk_write(data, pclk->param.csr_reg +
  441. pclk->param.reg_csr_offset);
  442. /* Second disable the clock */
  443. data = xgene_clk_read(pclk->param.csr_reg +
  444. pclk->param.reg_clk_offset);
  445. data &= ~pclk->param.reg_clk_mask;
  446. xgene_clk_write(data, pclk->param.csr_reg +
  447. pclk->param.reg_clk_offset);
  448. }
  449. if (pclk->lock)
  450. spin_unlock_irqrestore(pclk->lock, flags);
  451. }
  452. static int xgene_clk_is_enabled(struct clk_hw *hw)
  453. {
  454. struct xgene_clk *pclk = to_xgene_clk(hw);
  455. u32 data = 0;
  456. if (pclk->param.csr_reg) {
  457. pr_debug("%s clock checking\n", clk_hw_get_name(hw));
  458. data = xgene_clk_read(pclk->param.csr_reg +
  459. pclk->param.reg_clk_offset);
  460. pr_debug("%s clock is %s\n", clk_hw_get_name(hw),
  461. data & pclk->param.reg_clk_mask ? "enabled" :
  462. "disabled");
  463. }
  464. if (!pclk->param.csr_reg)
  465. return 1;
  466. return data & pclk->param.reg_clk_mask ? 1 : 0;
  467. }
  468. static unsigned long xgene_clk_recalc_rate(struct clk_hw *hw,
  469. unsigned long parent_rate)
  470. {
  471. struct xgene_clk *pclk = to_xgene_clk(hw);
  472. u32 data;
  473. if (pclk->param.divider_reg) {
  474. data = xgene_clk_read(pclk->param.divider_reg +
  475. pclk->param.reg_divider_offset);
  476. data >>= pclk->param.reg_divider_shift;
  477. data &= (1 << pclk->param.reg_divider_width) - 1;
  478. pr_debug("%s clock recalc rate %ld parent %ld\n",
  479. clk_hw_get_name(hw),
  480. parent_rate / data, parent_rate);
  481. return parent_rate / data;
  482. } else {
  483. pr_debug("%s clock recalc rate %ld parent %ld\n",
  484. clk_hw_get_name(hw), parent_rate, parent_rate);
  485. return parent_rate;
  486. }
  487. }
  488. static int xgene_clk_set_rate(struct clk_hw *hw, unsigned long rate,
  489. unsigned long parent_rate)
  490. {
  491. struct xgene_clk *pclk = to_xgene_clk(hw);
  492. unsigned long flags = 0;
  493. u32 data;
  494. u32 divider;
  495. u32 divider_save;
  496. if (pclk->lock)
  497. spin_lock_irqsave(pclk->lock, flags);
  498. if (pclk->param.divider_reg) {
  499. /* Let's compute the divider */
  500. if (rate > parent_rate)
  501. rate = parent_rate;
  502. divider_save = divider = parent_rate / rate; /* Rounded down */
  503. divider &= (1 << pclk->param.reg_divider_width) - 1;
  504. divider <<= pclk->param.reg_divider_shift;
  505. /* Set new divider */
  506. data = xgene_clk_read(pclk->param.divider_reg +
  507. pclk->param.reg_divider_offset);
  508. data &= ~(((1 << pclk->param.reg_divider_width) - 1)
  509. << pclk->param.reg_divider_shift);
  510. data |= divider;
  511. xgene_clk_write(data, pclk->param.divider_reg +
  512. pclk->param.reg_divider_offset);
  513. pr_debug("%s clock set rate %ld\n", clk_hw_get_name(hw),
  514. parent_rate / divider_save);
  515. } else {
  516. divider_save = 1;
  517. }
  518. if (pclk->lock)
  519. spin_unlock_irqrestore(pclk->lock, flags);
  520. return parent_rate / divider_save;
  521. }
  522. static long xgene_clk_round_rate(struct clk_hw *hw, unsigned long rate,
  523. unsigned long *prate)
  524. {
  525. struct xgene_clk *pclk = to_xgene_clk(hw);
  526. unsigned long parent_rate = *prate;
  527. u32 divider;
  528. if (pclk->param.divider_reg) {
  529. /* Let's compute the divider */
  530. if (rate > parent_rate)
  531. rate = parent_rate;
  532. divider = parent_rate / rate; /* Rounded down */
  533. } else {
  534. divider = 1;
  535. }
  536. return parent_rate / divider;
  537. }
  538. static const struct clk_ops xgene_clk_ops = {
  539. .enable = xgene_clk_enable,
  540. .disable = xgene_clk_disable,
  541. .is_enabled = xgene_clk_is_enabled,
  542. .recalc_rate = xgene_clk_recalc_rate,
  543. .set_rate = xgene_clk_set_rate,
  544. .round_rate = xgene_clk_round_rate,
  545. };
  546. static struct clk *xgene_register_clk(struct device *dev,
  547. const char *name, const char *parent_name,
  548. struct xgene_dev_parameters *parameters, spinlock_t *lock)
  549. {
  550. struct xgene_clk *apmclk;
  551. struct clk *clk;
  552. struct clk_init_data init;
  553. int rc;
  554. /* allocate the APM clock structure */
  555. apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
  556. if (!apmclk)
  557. return ERR_PTR(-ENOMEM);
  558. init.name = name;
  559. init.ops = &xgene_clk_ops;
  560. init.flags = 0;
  561. init.parent_names = parent_name ? &parent_name : NULL;
  562. init.num_parents = parent_name ? 1 : 0;
  563. apmclk->lock = lock;
  564. apmclk->hw.init = &init;
  565. apmclk->param = *parameters;
  566. /* Register the clock */
  567. clk = clk_register(dev, &apmclk->hw);
  568. if (IS_ERR(clk)) {
  569. pr_err("%s: could not register clk %s\n", __func__, name);
  570. kfree(apmclk);
  571. return clk;
  572. }
  573. /* Register the clock for lookup */
  574. rc = clk_register_clkdev(clk, name, NULL);
  575. if (rc != 0) {
  576. pr_err("%s: could not register lookup clk %s\n",
  577. __func__, name);
  578. }
  579. return clk;
  580. }
  581. static void __init xgene_devclk_init(struct device_node *np)
  582. {
  583. const char *clk_name = np->full_name;
  584. struct clk *clk;
  585. struct resource res;
  586. int rc;
  587. struct xgene_dev_parameters parameters;
  588. int i;
  589. /* Check if the entry is disabled */
  590. if (!of_device_is_available(np))
  591. return;
  592. /* Parse the DTS register for resource */
  593. parameters.csr_reg = NULL;
  594. parameters.divider_reg = NULL;
  595. for (i = 0; i < 2; i++) {
  596. void __iomem *map_res;
  597. rc = of_address_to_resource(np, i, &res);
  598. if (rc != 0) {
  599. if (i == 0) {
  600. pr_err("no DTS register for %pOF\n", np);
  601. return;
  602. }
  603. break;
  604. }
  605. map_res = of_iomap(np, i);
  606. if (!map_res) {
  607. pr_err("Unable to map resource %d for %pOF\n", i, np);
  608. goto err;
  609. }
  610. if (strcmp(res.name, "div-reg") == 0)
  611. parameters.divider_reg = map_res;
  612. else /* if (strcmp(res->name, "csr-reg") == 0) */
  613. parameters.csr_reg = map_res;
  614. }
  615. if (of_property_read_u32(np, "csr-offset", &parameters.reg_csr_offset))
  616. parameters.reg_csr_offset = 0;
  617. if (of_property_read_u32(np, "csr-mask", &parameters.reg_csr_mask))
  618. parameters.reg_csr_mask = 0xF;
  619. if (of_property_read_u32(np, "enable-offset",
  620. &parameters.reg_clk_offset))
  621. parameters.reg_clk_offset = 0x8;
  622. if (of_property_read_u32(np, "enable-mask", &parameters.reg_clk_mask))
  623. parameters.reg_clk_mask = 0xF;
  624. if (of_property_read_u32(np, "divider-offset",
  625. &parameters.reg_divider_offset))
  626. parameters.reg_divider_offset = 0;
  627. if (of_property_read_u32(np, "divider-width",
  628. &parameters.reg_divider_width))
  629. parameters.reg_divider_width = 0;
  630. if (of_property_read_u32(np, "divider-shift",
  631. &parameters.reg_divider_shift))
  632. parameters.reg_divider_shift = 0;
  633. of_property_read_string(np, "clock-output-names", &clk_name);
  634. clk = xgene_register_clk(NULL, clk_name,
  635. of_clk_get_parent_name(np, 0), &parameters, &clk_lock);
  636. if (IS_ERR(clk))
  637. goto err;
  638. pr_debug("Add %s clock\n", clk_name);
  639. rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
  640. if (rc != 0)
  641. pr_err("%s: could register provider clk %pOF\n", __func__, np);
  642. return;
  643. err:
  644. if (parameters.csr_reg)
  645. iounmap(parameters.csr_reg);
  646. if (parameters.divider_reg)
  647. iounmap(parameters.divider_reg);
  648. }
  649. CLK_OF_DECLARE(xgene_socpll_clock, "apm,xgene-socpll-clock", xgene_socpllclk_init);
  650. CLK_OF_DECLARE(xgene_pcppll_clock, "apm,xgene-pcppll-clock", xgene_pcppllclk_init);
  651. CLK_OF_DECLARE(xgene_pmd_clock, "apm,xgene-pmd-clock", xgene_pmdclk_init);
  652. CLK_OF_DECLARE(xgene_socpll_v2_clock, "apm,xgene-socpll-v2-clock",
  653. xgene_socpllclk_init);
  654. CLK_OF_DECLARE(xgene_pcppll_v2_clock, "apm,xgene-pcppll-v2-clock",
  655. xgene_pcppllclk_init);
  656. CLK_OF_DECLARE(xgene_dev_clock, "apm,xgene-device-clock", xgene_devclk_init);