2 * clk-xgene.c - AppliedMicro X-Gene Clock Interface
4 * Copyright (c) 2013, Applied Micro Circuits Corporation
5 * Author: Loc Ho <lho@apm.com>
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.
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.
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,
23 #include <linux/module.h>
24 #include <linux/spinlock.h>
27 #include <linux/clkdev.h>
28 #include <linux/clk-provider.h>
29 #include <linux/of_address.h>
31 /* Register SCU_PCPPLL bit fields */
32 #define N_DIV_RD(src) ((src) & 0x000001ff)
33 #define SC_N_DIV_RD(src) ((src) & 0x0000007f)
34 #define SC_OUTDIV2(src) (((src) & 0x00000100) >> 8)
36 /* Register SCU_SOCPLL bit fields */
37 #define CLKR_RD(src) (((src) & 0x07000000)>>24)
38 #define CLKOD_RD(src) (((src) & 0x00300000)>>20)
39 #define REGSPEC_RESET_F1_MASK 0x00010000
40 #define CLKF_RD(src) (((src) & 0x000001ff))
42 #define XGENE_CLK_DRIVER_VER "0.1"
44 static DEFINE_SPINLOCK(clk_lock);
46 static inline u32 xgene_clk_read(void __iomem *csr)
48 return readl_relaxed(csr);
51 static inline void xgene_clk_write(u32 data, void __iomem *csr)
53 writel_relaxed(data, csr);
62 struct xgene_clk_pll {
67 enum xgene_pll_type type;
71 #define to_xgene_clk_pll(_hw) container_of(_hw, struct xgene_clk_pll, hw)
73 static int xgene_clk_pll_is_enabled(struct clk_hw *hw)
75 struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
78 data = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
79 pr_debug("%s pll %s\n", clk_hw_get_name(hw),
80 data & REGSPEC_RESET_F1_MASK ? "disabled" : "enabled");
82 return data & REGSPEC_RESET_F1_MASK ? 0 : 1;
85 static unsigned long xgene_clk_pll_recalc_rate(struct clk_hw *hw,
86 unsigned long parent_rate)
88 struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
96 pll = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
98 if (pllclk->version <= 1) {
99 if (pllclk->type == PLL_TYPE_PCP) {
101 * PLL VCO = Reference clock * NF
102 * PCP PLL = PLL_VCO / 2
105 fvco = parent_rate * (N_DIV_RD(pll) + 4);
108 * Fref = Reference Clock / NREF;
110 * Fout = Fvco / NOUT;
112 nref = CLKR_RD(pll) + 1;
113 nout = CLKOD_RD(pll) + 1;
115 fref = parent_rate / nref;
120 * fvco = Reference clock * FBDIVC
121 * PLL freq = fvco / NOUT
123 nout = SC_OUTDIV2(pll) ? 2 : 3;
124 fvco = parent_rate * SC_N_DIV_RD(pll);
126 pr_debug("%s pll recalc rate %ld parent %ld version %d\n",
127 clk_hw_get_name(hw), fvco / nout, parent_rate,
133 static const struct clk_ops xgene_clk_pll_ops = {
134 .is_enabled = xgene_clk_pll_is_enabled,
135 .recalc_rate = xgene_clk_pll_recalc_rate,
138 static struct clk *xgene_register_clk_pll(struct device *dev,
139 const char *name, const char *parent_name,
140 unsigned long flags, void __iomem *reg, u32 pll_offset,
141 u32 type, spinlock_t *lock, int version)
143 struct xgene_clk_pll *apmclk;
145 struct clk_init_data init;
147 /* allocate the APM clock structure */
148 apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
150 return ERR_PTR(-ENOMEM);
153 init.ops = &xgene_clk_pll_ops;
155 init.parent_names = parent_name ? &parent_name : NULL;
156 init.num_parents = parent_name ? 1 : 0;
158 apmclk->version = version;
161 apmclk->pll_offset = pll_offset;
163 apmclk->hw.init = &init;
165 /* Register the clock */
166 clk = clk_register(dev, &apmclk->hw);
168 pr_err("%s: could not register clk %s\n", __func__, name);
175 static int xgene_pllclk_version(struct device_node *np)
177 if (of_device_is_compatible(np, "apm,xgene-socpll-clock"))
179 if (of_device_is_compatible(np, "apm,xgene-pcppll-clock"))
184 static void xgene_pllclk_init(struct device_node *np, enum xgene_pll_type pll_type)
186 const char *clk_name = np->full_name;
189 int version = xgene_pllclk_version(np);
191 reg = of_iomap(np, 0);
193 pr_err("Unable to map CSR register for %pOF\n", np);
196 of_property_read_string(np, "clock-output-names", &clk_name);
197 clk = xgene_register_clk_pll(NULL,
198 clk_name, of_clk_get_parent_name(np, 0),
199 0, reg, 0, pll_type, &clk_lock,
202 of_clk_add_provider(np, of_clk_src_simple_get, clk);
203 clk_register_clkdev(clk, clk_name, NULL);
204 pr_debug("Add %s clock PLL\n", clk_name);
208 static void xgene_socpllclk_init(struct device_node *np)
210 xgene_pllclk_init(np, PLL_TYPE_SOC);
213 static void xgene_pcppllclk_init(struct device_node *np)
215 xgene_pllclk_init(np, PLL_TYPE_PCP);
219 * struct xgene_clk_pmd - PMD clock
221 * @hw: handle between common and hardware-specific interfaces
222 * @reg: register containing the fractional scale multiplier (scaler)
223 * @shift: shift to the unit bit field
224 * @denom: 1/denominator unit
225 * @lock: register lock
227 * XGENE_CLK_PMD_SCALE_INVERTED - By default the scaler is the value read
228 * from the register plus one. For example,
229 * 0 for (0 + 1) / denom,
230 * 1 for (1 + 1) / denom and etc.
231 * If this flag is set, it is
232 * 0 for (denom - 0) / denom,
233 * 1 for (denom - 1) / denom and etc.
236 struct xgene_clk_pmd {
246 #define to_xgene_clk_pmd(_hw) container_of(_hw, struct xgene_clk_pmd, hw)
248 #define XGENE_CLK_PMD_SCALE_INVERTED BIT(0)
249 #define XGENE_CLK_PMD_SHIFT 8
250 #define XGENE_CLK_PMD_WIDTH 3
252 static unsigned long xgene_clk_pmd_recalc_rate(struct clk_hw *hw,
253 unsigned long parent_rate)
255 struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
256 unsigned long flags = 0;
261 spin_lock_irqsave(fd->lock, flags);
265 val = clk_readl(fd->reg);
268 spin_unlock_irqrestore(fd->lock, flags);
272 ret = (u64)parent_rate;
274 scale = (val & fd->mask) >> fd->shift;
275 if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
276 scale = fd->denom - scale;
280 /* freq = parent_rate * scaler / denom */
281 do_div(ret, fd->denom);
284 ret = (u64)parent_rate;
289 static long xgene_clk_pmd_round_rate(struct clk_hw *hw, unsigned long rate,
290 unsigned long *parent_rate)
292 struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
295 if (!rate || rate >= *parent_rate)
298 /* freq = parent_rate * scaler / denom */
299 ret = rate * fd->denom;
300 scale = DIV_ROUND_UP_ULL(ret, *parent_rate);
302 ret = (u64)*parent_rate * scale;
303 do_div(ret, fd->denom);
308 static int xgene_clk_pmd_set_rate(struct clk_hw *hw, unsigned long rate,
309 unsigned long parent_rate)
311 struct xgene_clk_pmd *fd = to_xgene_clk_pmd(hw);
312 unsigned long flags = 0;
317 * Compute the scaler:
319 * freq = parent_rate * scaler / denom, or
320 * scaler = freq * denom / parent_rate
322 ret = rate * fd->denom;
323 scale = DIV_ROUND_UP_ULL(ret, (u64)parent_rate);
325 /* Check if inverted */
326 if (fd->flags & XGENE_CLK_PMD_SCALE_INVERTED)
327 scale = fd->denom - scale;
332 spin_lock_irqsave(fd->lock, flags);
336 val = clk_readl(fd->reg);
338 val |= (scale << fd->shift);
339 clk_writel(val, fd->reg);
342 spin_unlock_irqrestore(fd->lock, flags);
349 static const struct clk_ops xgene_clk_pmd_ops = {
350 .recalc_rate = xgene_clk_pmd_recalc_rate,
351 .round_rate = xgene_clk_pmd_round_rate,
352 .set_rate = xgene_clk_pmd_set_rate,
356 xgene_register_clk_pmd(struct device *dev,
357 const char *name, const char *parent_name,
358 unsigned long flags, void __iomem *reg, u8 shift,
359 u8 width, u64 denom, u32 clk_flags, spinlock_t *lock)
361 struct xgene_clk_pmd *fd;
362 struct clk_init_data init;
365 fd = kzalloc(sizeof(*fd), GFP_KERNEL);
367 return ERR_PTR(-ENOMEM);
370 init.ops = &xgene_clk_pmd_ops;
372 init.parent_names = parent_name ? &parent_name : NULL;
373 init.num_parents = parent_name ? 1 : 0;
377 fd->mask = (BIT(width) - 1) << shift;
379 fd->flags = clk_flags;
383 clk = clk_register(dev, &fd->hw);
385 pr_err("%s: could not register clk %s\n", __func__, name);
393 static void xgene_pmdclk_init(struct device_node *np)
395 const char *clk_name = np->full_name;
396 void __iomem *csr_reg;
403 /* Check if the entry is disabled */
404 if (!of_device_is_available(np))
407 /* Parse the DTS register for resource */
408 rc = of_address_to_resource(np, 0, &res);
410 pr_err("no DTS register for %pOF\n", np);
413 csr_reg = of_iomap(np, 0);
415 pr_err("Unable to map resource for %pOF\n", np);
418 of_property_read_string(np, "clock-output-names", &clk_name);
420 denom = BIT(XGENE_CLK_PMD_WIDTH);
421 flags |= XGENE_CLK_PMD_SCALE_INVERTED;
423 clk = xgene_register_clk_pmd(NULL, clk_name,
424 of_clk_get_parent_name(np, 0), 0,
425 csr_reg, XGENE_CLK_PMD_SHIFT,
426 XGENE_CLK_PMD_WIDTH, denom,
429 of_clk_add_provider(np, of_clk_src_simple_get, clk);
430 clk_register_clkdev(clk, clk_name, NULL);
431 pr_debug("Add %s clock\n", clk_name);
439 struct xgene_dev_parameters {
440 void __iomem *csr_reg; /* CSR for IP clock */
441 u32 reg_clk_offset; /* Offset to clock enable CSR */
442 u32 reg_clk_mask; /* Mask bit for clock enable */
443 u32 reg_csr_offset; /* Offset to CSR reset */
444 u32 reg_csr_mask; /* Mask bit for disable CSR reset */
445 void __iomem *divider_reg; /* CSR for divider */
446 u32 reg_divider_offset; /* Offset to divider register */
447 u32 reg_divider_shift; /* Bit shift to divider field */
448 u32 reg_divider_width; /* Width of the bit to divider field */
454 struct xgene_dev_parameters param;
457 #define to_xgene_clk(_hw) container_of(_hw, struct xgene_clk, hw)
459 static int xgene_clk_enable(struct clk_hw *hw)
461 struct xgene_clk *pclk = to_xgene_clk(hw);
462 unsigned long flags = 0;
466 spin_lock_irqsave(pclk->lock, flags);
468 if (pclk->param.csr_reg) {
469 pr_debug("%s clock enabled\n", clk_hw_get_name(hw));
470 /* First enable the clock */
471 data = xgene_clk_read(pclk->param.csr_reg +
472 pclk->param.reg_clk_offset);
473 data |= pclk->param.reg_clk_mask;
474 xgene_clk_write(data, pclk->param.csr_reg +
475 pclk->param.reg_clk_offset);
476 pr_debug("%s clk offset 0x%08X mask 0x%08X value 0x%08X\n",
478 pclk->param.reg_clk_offset, pclk->param.reg_clk_mask,
481 /* Second enable the CSR */
482 data = xgene_clk_read(pclk->param.csr_reg +
483 pclk->param.reg_csr_offset);
484 data &= ~pclk->param.reg_csr_mask;
485 xgene_clk_write(data, pclk->param.csr_reg +
486 pclk->param.reg_csr_offset);
487 pr_debug("%s csr offset 0x%08X mask 0x%08X value 0x%08X\n",
489 pclk->param.reg_csr_offset, pclk->param.reg_csr_mask,
494 spin_unlock_irqrestore(pclk->lock, flags);
499 static void xgene_clk_disable(struct clk_hw *hw)
501 struct xgene_clk *pclk = to_xgene_clk(hw);
502 unsigned long flags = 0;
506 spin_lock_irqsave(pclk->lock, flags);
508 if (pclk->param.csr_reg) {
509 pr_debug("%s clock disabled\n", clk_hw_get_name(hw));
510 /* First put the CSR in reset */
511 data = xgene_clk_read(pclk->param.csr_reg +
512 pclk->param.reg_csr_offset);
513 data |= pclk->param.reg_csr_mask;
514 xgene_clk_write(data, pclk->param.csr_reg +
515 pclk->param.reg_csr_offset);
517 /* Second disable the clock */
518 data = xgene_clk_read(pclk->param.csr_reg +
519 pclk->param.reg_clk_offset);
520 data &= ~pclk->param.reg_clk_mask;
521 xgene_clk_write(data, pclk->param.csr_reg +
522 pclk->param.reg_clk_offset);
526 spin_unlock_irqrestore(pclk->lock, flags);
529 static int xgene_clk_is_enabled(struct clk_hw *hw)
531 struct xgene_clk *pclk = to_xgene_clk(hw);
534 if (pclk->param.csr_reg) {
535 pr_debug("%s clock checking\n", clk_hw_get_name(hw));
536 data = xgene_clk_read(pclk->param.csr_reg +
537 pclk->param.reg_clk_offset);
538 pr_debug("%s clock is %s\n", clk_hw_get_name(hw),
539 data & pclk->param.reg_clk_mask ? "enabled" :
543 if (!pclk->param.csr_reg)
545 return data & pclk->param.reg_clk_mask ? 1 : 0;
548 static unsigned long xgene_clk_recalc_rate(struct clk_hw *hw,
549 unsigned long parent_rate)
551 struct xgene_clk *pclk = to_xgene_clk(hw);
554 if (pclk->param.divider_reg) {
555 data = xgene_clk_read(pclk->param.divider_reg +
556 pclk->param.reg_divider_offset);
557 data >>= pclk->param.reg_divider_shift;
558 data &= (1 << pclk->param.reg_divider_width) - 1;
560 pr_debug("%s clock recalc rate %ld parent %ld\n",
562 parent_rate / data, parent_rate);
564 return parent_rate / data;
566 pr_debug("%s clock recalc rate %ld parent %ld\n",
567 clk_hw_get_name(hw), parent_rate, parent_rate);
572 static int xgene_clk_set_rate(struct clk_hw *hw, unsigned long rate,
573 unsigned long parent_rate)
575 struct xgene_clk *pclk = to_xgene_clk(hw);
576 unsigned long flags = 0;
582 spin_lock_irqsave(pclk->lock, flags);
584 if (pclk->param.divider_reg) {
585 /* Let's compute the divider */
586 if (rate > parent_rate)
588 divider_save = divider = parent_rate / rate; /* Rounded down */
589 divider &= (1 << pclk->param.reg_divider_width) - 1;
590 divider <<= pclk->param.reg_divider_shift;
592 /* Set new divider */
593 data = xgene_clk_read(pclk->param.divider_reg +
594 pclk->param.reg_divider_offset);
595 data &= ~(((1 << pclk->param.reg_divider_width) - 1)
596 << pclk->param.reg_divider_shift);
598 xgene_clk_write(data, pclk->param.divider_reg +
599 pclk->param.reg_divider_offset);
600 pr_debug("%s clock set rate %ld\n", clk_hw_get_name(hw),
601 parent_rate / divider_save);
607 spin_unlock_irqrestore(pclk->lock, flags);
609 return parent_rate / divider_save;
612 static long xgene_clk_round_rate(struct clk_hw *hw, unsigned long rate,
613 unsigned long *prate)
615 struct xgene_clk *pclk = to_xgene_clk(hw);
616 unsigned long parent_rate = *prate;
619 if (pclk->param.divider_reg) {
620 /* Let's compute the divider */
621 if (rate > parent_rate)
623 divider = parent_rate / rate; /* Rounded down */
628 return parent_rate / divider;
631 static const struct clk_ops xgene_clk_ops = {
632 .enable = xgene_clk_enable,
633 .disable = xgene_clk_disable,
634 .is_enabled = xgene_clk_is_enabled,
635 .recalc_rate = xgene_clk_recalc_rate,
636 .set_rate = xgene_clk_set_rate,
637 .round_rate = xgene_clk_round_rate,
640 static struct clk *xgene_register_clk(struct device *dev,
641 const char *name, const char *parent_name,
642 struct xgene_dev_parameters *parameters, spinlock_t *lock)
644 struct xgene_clk *apmclk;
646 struct clk_init_data init;
649 /* allocate the APM clock structure */
650 apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
652 return ERR_PTR(-ENOMEM);
655 init.ops = &xgene_clk_ops;
657 init.parent_names = parent_name ? &parent_name : NULL;
658 init.num_parents = parent_name ? 1 : 0;
661 apmclk->hw.init = &init;
662 apmclk->param = *parameters;
664 /* Register the clock */
665 clk = clk_register(dev, &apmclk->hw);
667 pr_err("%s: could not register clk %s\n", __func__, name);
672 /* Register the clock for lookup */
673 rc = clk_register_clkdev(clk, name, NULL);
675 pr_err("%s: could not register lookup clk %s\n",
681 static void __init xgene_devclk_init(struct device_node *np)
683 const char *clk_name = np->full_name;
687 struct xgene_dev_parameters parameters;
690 /* Check if the entry is disabled */
691 if (!of_device_is_available(np))
694 /* Parse the DTS register for resource */
695 parameters.csr_reg = NULL;
696 parameters.divider_reg = NULL;
697 for (i = 0; i < 2; i++) {
698 void __iomem *map_res;
699 rc = of_address_to_resource(np, i, &res);
702 pr_err("no DTS register for %pOF\n", np);
707 map_res = of_iomap(np, i);
709 pr_err("Unable to map resource %d for %pOF\n", i, np);
712 if (strcmp(res.name, "div-reg") == 0)
713 parameters.divider_reg = map_res;
714 else /* if (strcmp(res->name, "csr-reg") == 0) */
715 parameters.csr_reg = map_res;
717 if (of_property_read_u32(np, "csr-offset", ¶meters.reg_csr_offset))
718 parameters.reg_csr_offset = 0;
719 if (of_property_read_u32(np, "csr-mask", ¶meters.reg_csr_mask))
720 parameters.reg_csr_mask = 0xF;
721 if (of_property_read_u32(np, "enable-offset",
722 ¶meters.reg_clk_offset))
723 parameters.reg_clk_offset = 0x8;
724 if (of_property_read_u32(np, "enable-mask", ¶meters.reg_clk_mask))
725 parameters.reg_clk_mask = 0xF;
726 if (of_property_read_u32(np, "divider-offset",
727 ¶meters.reg_divider_offset))
728 parameters.reg_divider_offset = 0;
729 if (of_property_read_u32(np, "divider-width",
730 ¶meters.reg_divider_width))
731 parameters.reg_divider_width = 0;
732 if (of_property_read_u32(np, "divider-shift",
733 ¶meters.reg_divider_shift))
734 parameters.reg_divider_shift = 0;
735 of_property_read_string(np, "clock-output-names", &clk_name);
737 clk = xgene_register_clk(NULL, clk_name,
738 of_clk_get_parent_name(np, 0), ¶meters, &clk_lock);
741 pr_debug("Add %s clock\n", clk_name);
742 rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
744 pr_err("%s: could register provider clk %pOF\n", __func__, np);
749 if (parameters.csr_reg)
750 iounmap(parameters.csr_reg);
751 if (parameters.divider_reg)
752 iounmap(parameters.divider_reg);
755 CLK_OF_DECLARE(xgene_socpll_clock, "apm,xgene-socpll-clock", xgene_socpllclk_init);
756 CLK_OF_DECLARE(xgene_pcppll_clock, "apm,xgene-pcppll-clock", xgene_pcppllclk_init);
757 CLK_OF_DECLARE(xgene_pmd_clock, "apm,xgene-pmd-clock", xgene_pmdclk_init);
758 CLK_OF_DECLARE(xgene_socpll_v2_clock, "apm,xgene-socpll-v2-clock",
759 xgene_socpllclk_init);
760 CLK_OF_DECLARE(xgene_pcppll_v2_clock, "apm,xgene-pcppll-v2-clock",
761 xgene_pcppllclk_init);
762 CLK_OF_DECLARE(xgene_dev_clock, "apm,xgene-device-clock", xgene_devclk_init);