xref: /freebsd/sys/arm/freescale/imx/imx6_pl310.c (revision 4b330699f819a81d8e34d471225143ffeb321855)
1 /*-
2  * Copyright (c) 2012 Olivier Houchard.
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 ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 /*
30  * The machine-dependent part of the arm/pl310 driver for imx6 SoCs.
31  */
32 
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/bus.h>
37 #include <sys/rman.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 
41 #include <machine/bus.h>
42 #include <machine/pl310.h>
43 #include <machine/platformvar.h>
44 
45 #include <arm/freescale/imx/imx6_machdep.h>
46 
47 #include "platform_pl310_if.h"
48 
49 void
50 imx6_pl310_init(platform_t plat, struct pl310_softc *sc)
51 {
52 	uint32_t reg;
53 
54 	/*
55 	 * Enable power saving modes:
56 	 *  - Dynamic Gating stops the clock when the controller is idle.
57 	 *  - Standby stops the clock when the cores are in WFI mode.
58 	 */
59 	reg = pl310_read4(sc, PL310_POWER_CTRL);
60 	reg |= POWER_CTRL_ENABLE_GATING | POWER_CTRL_ENABLE_STANDBY;
61 	pl310_write4(sc, PL310_POWER_CTRL, reg);
62 
63 	pl310_set_ram_latency(sc, PL310_TAG_RAM_CTRL,  4, 2, 3);
64 	pl310_set_ram_latency(sc, PL310_DATA_RAM_CTRL, 4, 2, 3);
65 }
66