xref: /freebsd/sys/arm/freescale/imx/imx6_pl310.c (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012 Olivier Houchard.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 /*
32  * The machine-dependent part of the arm/pl310 driver for imx6 SoCs.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/rman.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 
43 #include <machine/bus.h>
44 #include <machine/pl310.h>
45 #include <machine/platformvar.h>
46 
47 #include <arm/freescale/imx/imx6_machdep.h>
48 
49 #include "platform_pl310_if.h"
50 
51 void
52 imx6_pl310_init(platform_t plat, struct pl310_softc *sc)
53 {
54 	uint32_t reg;
55 
56 	/*
57 	 * Enable power saving modes:
58 	 *  - Dynamic Gating stops the clock when the controller is idle.
59 	 *  - Standby stops the clock when the cores are in WFI mode.
60 	 */
61 	reg = pl310_read4(sc, PL310_POWER_CTRL);
62 	reg |= POWER_CTRL_ENABLE_GATING | POWER_CTRL_ENABLE_STANDBY;
63 	pl310_write4(sc, PL310_POWER_CTRL, reg);
64 
65 	pl310_set_ram_latency(sc, PL310_TAG_RAM_CTRL,  4, 2, 3);
66 	pl310_set_ram_latency(sc, PL310_DATA_RAM_CTRL, 4, 2, 3);
67 }
68