xref: /freebsd/sys/arm/freescale/imx/imx6_ccm.c (revision f02f7422801bb39f5eaab8fc383fa7b70c467ff9)
1 /*-
2  * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 /*
31  * Clocks and power control driver for Freescale i.MX6 family of SoCs.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/bus.h>
39 #include <sys/rman.h>
40 
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
43 
44 #include <machine/bus.h>
45 
46 #include <arm/freescale/imx/imx6_anatopreg.h>
47 #include <arm/freescale/imx/imx6_anatopvar.h>
48 #include <arm/freescale/imx/imx6_ccmreg.h>
49 #include <arm/freescale/imx/imx_machdep.h>
50 #include <arm/freescale/imx/imx_ccmvar.h>
51 
52 #ifndef CCGR_CLK_MODE_ALWAYS
53 #define	CCGR_CLK_MODE_OFF		0
54 #define	CCGR_CLK_MODE_RUNMODE		1
55 #define	CCGR_CLK_MODE_ALWAYS		3
56 #endif
57 
58 struct ccm_softc {
59 	device_t	dev;
60 	struct resource	*mem_res;
61 };
62 
63 static struct ccm_softc *ccm_sc;
64 
65 static inline uint32_t
66 RD4(struct ccm_softc *sc, bus_size_t off)
67 {
68 
69 	return (bus_read_4(sc->mem_res, off));
70 }
71 
72 static inline void
73 WR4(struct ccm_softc *sc, bus_size_t off, uint32_t val)
74 {
75 
76 	bus_write_4(sc->mem_res, off, val);
77 }
78 
79 static int
80 ccm_detach(device_t dev)
81 {
82 	struct ccm_softc *sc;
83 
84 	sc = device_get_softc(dev);
85 
86 	if (sc->mem_res != NULL)
87 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
88 
89 	return (0);
90 }
91 
92 static int
93 ccm_attach(device_t dev)
94 {
95 	struct ccm_softc *sc;
96 	int err, rid;
97 	uint32_t reg;
98 
99 	sc = device_get_softc(dev);
100 	err = 0;
101 
102 	/* Allocate bus_space resources. */
103 	rid = 0;
104 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
105 	    RF_ACTIVE);
106 	if (sc->mem_res == NULL) {
107 		device_printf(dev, "Cannot allocate memory resources\n");
108 		err = ENXIO;
109 		goto out;
110 	}
111 
112 	ccm_sc = sc;
113 
114 	/*
115 	 * Configure the Low Power Mode setting to leave the ARM core power on
116 	 * when a WFI instruction is executed.  This lets the MPCore timers and
117 	 * GIC continue to run, which is helpful when the only thing that can
118 	 * wake you up is an MPCore Private Timer interrupt delivered via GIC.
119 	 *
120 	 * XXX Based on the docs, setting CCM_CGPR_INT_MEM_CLK_LPM shouldn't be
121 	 * required when the LPM bits are set to LPM_RUN.  But experimentally
122 	 * I've experienced a fairly rare lockup when not setting it.  I was
123 	 * unable to prove conclusively that the lockup was related to power
124 	 * management or that this definitively fixes it.  Revisit this.
125 	 */
126 	reg = RD4(sc, CCM_CGPR);
127 	reg |= CCM_CGPR_INT_MEM_CLK_LPM;
128 	WR4(sc, CCM_CGPR, reg);
129 	reg = RD4(sc, CCM_CLPCR);
130 	reg = (reg & ~CCM_CLPCR_LPM_MASK) | CCM_CLPCR_LPM_RUN;
131 	WR4(sc, CCM_CLPCR, reg);
132 
133 	err = 0;
134 
135 out:
136 
137 	if (err != 0)
138 		ccm_detach(dev);
139 
140 	return (err);
141 }
142 
143 static int
144 ccm_probe(device_t dev)
145 {
146 
147 	if (!ofw_bus_status_okay(dev))
148 		return (ENXIO);
149 
150         if (ofw_bus_is_compatible(dev, "fsl,imx6q-ccm") == 0)
151 		return (ENXIO);
152 
153 	device_set_desc(dev, "Freescale i.MX6 Clock Control Module");
154 
155 	return (BUS_PROBE_DEFAULT);
156 }
157 
158 void
159 imx_ccm_usb_enable(device_t _usbdev)
160 {
161 
162 	/*
163 	 * For imx6, the USBOH3 clock gate is bits 0-1 of CCGR6, so no need for
164 	 * shifting and masking here, just set the low-order two bits to ALWAYS.
165 	 */
166 	WR4(ccm_sc, CCM_CCGR6, RD4(ccm_sc, CCM_CCGR6) | CCGR_CLK_MODE_ALWAYS);
167 }
168 
169 void
170 imx_ccm_usbphy_enable(device_t _phydev)
171 {
172         /*
173          * XXX Which unit?
174          * Right now it's not clear how to figure from fdt data which phy unit
175          * we're supposed to operate on.  Until this is worked out, just enable
176          * both PHYs.
177          */
178 #if 0
179 	int phy_num, regoff;
180 
181 	phy_num = 0; /* XXX */
182 
183 	switch (phy_num) {
184 	case 0:
185 		regoff = 0;
186 		break;
187 	case 1:
188 		regoff = 0x10;
189 		break;
190 	default:
191 		device_printf(ccm_sc->dev, "Bad PHY number %u,\n",
192 		    phy_num);
193 		return;
194 	}
195 
196 	imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_USB1 + regoff,
197 	    IMX6_ANALOG_CCM_PLL_USB_ENABLE |
198 	    IMX6_ANALOG_CCM_PLL_USB_POWER |
199 	    IMX6_ANALOG_CCM_PLL_USB_EN_USB_CLKS);
200 #else
201 	imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_USB1 + 0,
202 	    IMX6_ANALOG_CCM_PLL_USB_ENABLE |
203 	    IMX6_ANALOG_CCM_PLL_USB_POWER |
204 	    IMX6_ANALOG_CCM_PLL_USB_EN_USB_CLKS);
205 
206 	imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_USB1 + 0x10,
207 	    IMX6_ANALOG_CCM_PLL_USB_ENABLE |
208 	    IMX6_ANALOG_CCM_PLL_USB_POWER |
209 	    IMX6_ANALOG_CCM_PLL_USB_EN_USB_CLKS);
210 #endif
211 }
212 
213 uint32_t
214 imx_ccm_ipg_hz(void)
215 {
216 
217 	return (66000000);
218 }
219 
220 uint32_t
221 imx_ccm_perclk_hz(void)
222 {
223 
224 	return (66000000);
225 }
226 
227 uint32_t
228 imx_ccm_sdhci_hz(void)
229 {
230 
231 	return (200000000);
232 }
233 
234 uint32_t
235 imx_ccm_uart_hz(void)
236 {
237 
238 	return (80000000);
239 }
240 
241 uint32_t
242 imx_ccm_ahb_hz(void)
243 {
244 	return (132000000);
245 }
246 
247 static device_method_t ccm_methods[] = {
248 	/* Device interface */
249 	DEVMETHOD(device_probe,  ccm_probe),
250 	DEVMETHOD(device_attach, ccm_attach),
251 	DEVMETHOD(device_detach, ccm_detach),
252 
253 	DEVMETHOD_END
254 };
255 
256 static driver_t ccm_driver = {
257 	"ccm",
258 	ccm_methods,
259 	sizeof(struct ccm_softc)
260 };
261 
262 static devclass_t ccm_devclass;
263 
264 DRIVER_MODULE(ccm, simplebus, ccm_driver, ccm_devclass, 0, 0);
265 
266