1 // SPDX-License-Identifier: GPL-2.0+
3 * Freescale i.MX23/i.MX28 clock setup code
5 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
6 * on behalf of DENX Software Engineering GmbH
8 * Based on code from LTIB:
9 * Copyright (C) 2010 Freescale Semiconductor, Inc.
13 #include <linux/errno.h>
15 #include <asm/arch/clock.h>
16 #include <asm/arch/imx-regs.h>
19 * The PLL frequency is 480MHz and XTAL frequency is 24MHz
20 * iMX23: datasheet section 4.2
21 * iMX28: datasheet section 10.2
23 #define PLL_FREQ_KHZ 480000
24 #define PLL_FREQ_COEF 18
25 #define XTAL_FREQ_KHZ 24000
27 #define PLL_FREQ_MHZ (PLL_FREQ_KHZ / 1000)
28 #define XTAL_FREQ_MHZ (XTAL_FREQ_KHZ / 1000)
30 #if defined(CONFIG_MX23)
31 #define MXC_SSPCLK_MAX MXC_SSPCLK0
32 #elif defined(CONFIG_MX28)
33 #define MXC_SSPCLK_MAX MXC_SSPCLK3
36 static uint32_t mxs_get_pclk(void)
38 struct mxs_clkctrl_regs *clkctrl_regs =
39 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
41 uint32_t clkctrl, clkseq, div;
42 uint8_t clkfrac, frac;
44 clkctrl = readl(&clkctrl_regs->hw_clkctrl_cpu);
46 /* No support of fractional divider calculation */
48 (CLKCTRL_CPU_DIV_XTAL_FRAC_EN | CLKCTRL_CPU_DIV_CPU_FRAC_EN)) {
52 clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
55 if (clkseq & CLKCTRL_CLKSEQ_BYPASS_CPU) {
56 div = (clkctrl & CLKCTRL_CPU_DIV_XTAL_MASK) >>
57 CLKCTRL_CPU_DIV_XTAL_OFFSET;
58 return XTAL_FREQ_MHZ / div;
62 clkfrac = readb(&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_CPU]);
63 frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
64 div = clkctrl & CLKCTRL_CPU_DIV_CPU_MASK;
65 return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
68 static uint32_t mxs_get_hclk(void)
70 struct mxs_clkctrl_regs *clkctrl_regs =
71 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
76 clkctrl = readl(&clkctrl_regs->hw_clkctrl_hbus);
78 /* No support of fractional divider calculation */
79 if (clkctrl & CLKCTRL_HBUS_DIV_FRAC_EN)
82 div = clkctrl & CLKCTRL_HBUS_DIV_MASK;
83 return mxs_get_pclk() / div;
86 static uint32_t mxs_get_emiclk(void)
88 struct mxs_clkctrl_regs *clkctrl_regs =
89 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
91 uint32_t clkctrl, clkseq, div;
92 uint8_t clkfrac, frac;
94 clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
95 clkctrl = readl(&clkctrl_regs->hw_clkctrl_emi);
98 if (clkseq & CLKCTRL_CLKSEQ_BYPASS_EMI) {
99 div = (clkctrl & CLKCTRL_EMI_DIV_XTAL_MASK) >>
100 CLKCTRL_EMI_DIV_XTAL_OFFSET;
101 return XTAL_FREQ_MHZ / div;
105 clkfrac = readb(&clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_EMI]);
106 frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
107 div = clkctrl & CLKCTRL_EMI_DIV_EMI_MASK;
108 return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
111 static uint32_t mxs_get_gpmiclk(void)
113 struct mxs_clkctrl_regs *clkctrl_regs =
114 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
115 #if defined(CONFIG_MX23)
117 &clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_CPU];
118 #elif defined(CONFIG_MX28)
120 &clkctrl_regs->hw_clkctrl_frac1[CLKCTRL_FRAC1_GPMI];
122 uint32_t clkctrl, clkseq, div;
123 uint8_t clkfrac, frac;
125 clkseq = readl(&clkctrl_regs->hw_clkctrl_clkseq);
126 clkctrl = readl(&clkctrl_regs->hw_clkctrl_gpmi);
129 if (clkseq & CLKCTRL_CLKSEQ_BYPASS_GPMI) {
130 div = clkctrl & CLKCTRL_GPMI_DIV_MASK;
131 return XTAL_FREQ_MHZ / div;
135 clkfrac = readb(reg);
136 frac = clkfrac & CLKCTRL_FRAC_FRAC_MASK;
137 div = clkctrl & CLKCTRL_GPMI_DIV_MASK;
138 return (PLL_FREQ_MHZ * PLL_FREQ_COEF / frac) / div;
142 * Set IO clock frequency, in kHz
144 void mxs_set_ioclk(enum mxs_ioclock io, uint32_t freq)
146 struct mxs_clkctrl_regs *clkctrl_regs =
147 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
154 if ((io < MXC_IOCLK0) || (io > MXC_IOCLK1))
157 div = (PLL_FREQ_KHZ * PLL_FREQ_COEF) / freq;
165 io_reg = CLKCTRL_FRAC0_IO0 - io; /* Register order is reversed */
166 writeb(CLKCTRL_FRAC_CLKGATE,
167 &clkctrl_regs->hw_clkctrl_frac0_set[io_reg]);
168 writeb(CLKCTRL_FRAC_CLKGATE | (div & CLKCTRL_FRAC_FRAC_MASK),
169 &clkctrl_regs->hw_clkctrl_frac0[io_reg]);
170 writeb(CLKCTRL_FRAC_CLKGATE,
171 &clkctrl_regs->hw_clkctrl_frac0_clr[io_reg]);
175 * Get IO clock, returns IO clock in kHz
177 static uint32_t mxs_get_ioclk(enum mxs_ioclock io)
179 struct mxs_clkctrl_regs *clkctrl_regs =
180 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
184 if ((io < MXC_IOCLK0) || (io > MXC_IOCLK1))
187 io_reg = CLKCTRL_FRAC0_IO0 - io; /* Register order is reversed */
189 ret = readb(&clkctrl_regs->hw_clkctrl_frac0[io_reg]) &
190 CLKCTRL_FRAC_FRAC_MASK;
192 return (PLL_FREQ_KHZ * PLL_FREQ_COEF) / ret;
196 * Configure SSP clock frequency, in kHz
198 void mxs_set_sspclk(enum mxs_sspclock ssp, uint32_t freq, int xtal)
200 struct mxs_clkctrl_regs *clkctrl_regs =
201 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
202 uint32_t clk, clkreg;
204 if (ssp > MXC_SSPCLK_MAX)
207 clkreg = (uint32_t)(&clkctrl_regs->hw_clkctrl_ssp0) +
208 (ssp * sizeof(struct mxs_register_32));
210 clrbits_le32(clkreg, CLKCTRL_SSP_CLKGATE);
211 while (readl(clkreg) & CLKCTRL_SSP_CLKGATE)
217 clk = mxs_get_ioclk(ssp >> 1);
222 /* Calculate the divider and cap it if necessary */
224 if (clk > CLKCTRL_SSP_DIV_MASK)
225 clk = CLKCTRL_SSP_DIV_MASK;
227 clrsetbits_le32(clkreg, CLKCTRL_SSP_DIV_MASK, clk);
228 while (readl(clkreg) & CLKCTRL_SSP_BUSY)
232 writel(CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp,
233 &clkctrl_regs->hw_clkctrl_clkseq_set);
235 writel(CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp,
236 &clkctrl_regs->hw_clkctrl_clkseq_clr);
240 * Return SSP frequency, in kHz
242 static uint32_t mxs_get_sspclk(enum mxs_sspclock ssp)
244 struct mxs_clkctrl_regs *clkctrl_regs =
245 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
249 if (ssp > MXC_SSPCLK_MAX)
252 tmp = readl(&clkctrl_regs->hw_clkctrl_clkseq);
253 if (tmp & (CLKCTRL_CLKSEQ_BYPASS_SSP0 << ssp))
254 return XTAL_FREQ_KHZ;
256 clkreg = (uint32_t)(&clkctrl_regs->hw_clkctrl_ssp0) +
257 (ssp * sizeof(struct mxs_register_32));
259 tmp = readl(clkreg) & CLKCTRL_SSP_DIV_MASK;
264 clk = mxs_get_ioclk(ssp >> 1);
270 * Set SSP/MMC bus frequency, in kHz)
272 void mxs_set_ssp_busclock(unsigned int bus, uint32_t freq)
274 struct mxs_ssp_regs *ssp_regs;
275 const enum mxs_sspclock clk = mxs_ssp_clock_by_bus(bus);
276 const uint32_t sspclk = mxs_get_sspclk(clk);
278 uint32_t divide, rate, tgtclk;
280 ssp_regs = mxs_ssp_regs_by_bus(bus);
283 * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
284 * CLOCK_DIVIDE has to be an even value from 2 to 254, and
285 * CLOCK_RATE could be any integer from 0 to 255.
287 for (divide = 2; divide < 254; divide += 2) {
288 rate = sspclk / freq / divide;
293 tgtclk = sspclk / divide / rate;
294 while (tgtclk > freq) {
296 tgtclk = sspclk / divide / rate;
301 /* Always set timeout the maximum */
302 reg = SSP_TIMING_TIMEOUT_MASK |
303 (divide << SSP_TIMING_CLOCK_DIVIDE_OFFSET) |
304 ((rate - 1) << SSP_TIMING_CLOCK_RATE_OFFSET);
305 writel(reg, &ssp_regs->hw_ssp_timing);
307 debug("SPI%d: Set freq rate to %d KHz (requested %d KHz)\n",
311 void mxs_set_lcdclk(uint32_t __maybe_unused lcd_base, uint32_t freq)
313 struct mxs_clkctrl_regs *clkctrl_regs =
314 (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE;
315 uint32_t fp, x, k_rest, k_best, x_best, tk;
316 int32_t k_best_l = 999, k_best_t = 0, x_best_l = 0xff, x_best_t = 0xff;
321 #if defined(CONFIG_MX23)
322 writel(CLKCTRL_CLKSEQ_BYPASS_PIX, &clkctrl_regs->hw_clkctrl_clkseq_clr);
323 #elif defined(CONFIG_MX28)
324 writel(CLKCTRL_CLKSEQ_BYPASS_DIS_LCDIF, &clkctrl_regs->hw_clkctrl_clkseq_clr);
329 * freq kHz = | 480000000 Hz * -- | * --- * ------
335 * k = -------------------
339 fp = ((PLL_FREQ_KHZ * 1000) / freq) * 18;
341 for (x = 18; x <= 35; x++) {
343 if ((tk / 1000 == 0) || (tk / 1000 > 255))
348 if (k_rest < (k_best_l % 1000)) {
353 if (k_rest > (k_best_t % 1000)) {
359 if (1000 - (k_best_t % 1000) > (k_best_l % 1000)) {
369 #if defined(CONFIG_MX23)
370 writeb(CLKCTRL_FRAC_CLKGATE,
371 &clkctrl_regs->hw_clkctrl_frac0_set[CLKCTRL_FRAC0_PIX]);
372 writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK),
373 &clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_PIX]);
374 writeb(CLKCTRL_FRAC_CLKGATE,
375 &clkctrl_regs->hw_clkctrl_frac0_clr[CLKCTRL_FRAC0_PIX]);
377 writel(CLKCTRL_PIX_CLKGATE,
378 &clkctrl_regs->hw_clkctrl_pix_set);
379 clrsetbits_le32(&clkctrl_regs->hw_clkctrl_pix,
380 CLKCTRL_PIX_DIV_MASK | CLKCTRL_PIX_CLKGATE,
381 k_best << CLKCTRL_PIX_DIV_OFFSET);
383 while (readl(&clkctrl_regs->hw_clkctrl_pix) & CLKCTRL_PIX_BUSY)
385 #elif defined(CONFIG_MX28)
386 writeb(CLKCTRL_FRAC_CLKGATE,
387 &clkctrl_regs->hw_clkctrl_frac1_set[CLKCTRL_FRAC1_PIX]);
388 writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK),
389 &clkctrl_regs->hw_clkctrl_frac1[CLKCTRL_FRAC1_PIX]);
390 writeb(CLKCTRL_FRAC_CLKGATE,
391 &clkctrl_regs->hw_clkctrl_frac1_clr[CLKCTRL_FRAC1_PIX]);
393 writel(CLKCTRL_DIS_LCDIF_CLKGATE,
394 &clkctrl_regs->hw_clkctrl_lcdif_set);
395 clrsetbits_le32(&clkctrl_regs->hw_clkctrl_lcdif,
396 CLKCTRL_DIS_LCDIF_DIV_MASK | CLKCTRL_DIS_LCDIF_CLKGATE,
397 k_best << CLKCTRL_DIS_LCDIF_DIV_OFFSET);
399 while (readl(&clkctrl_regs->hw_clkctrl_lcdif) & CLKCTRL_DIS_LCDIF_BUSY)
404 uint32_t mxc_get_clock(enum mxc_clock clk)
408 return mxs_get_pclk() * 1000000;
410 return mxs_get_gpmiclk() * 1000000;
413 return mxs_get_hclk() * 1000000;
415 return mxs_get_emiclk();
417 return mxs_get_ioclk(MXC_IOCLK0);
419 return mxs_get_ioclk(MXC_IOCLK1);
421 return XTAL_FREQ_KHZ * 1000;
423 return mxs_get_sspclk(MXC_SSPCLK0);
426 return mxs_get_sspclk(MXC_SSPCLK1);
428 return mxs_get_sspclk(MXC_SSPCLK2);
430 return mxs_get_sspclk(MXC_SSPCLK3);