xref: /openbmc/linux/drivers/usb/host/xhci-mvebu.c (revision 0da85d1e)
1 /*
2  * Copyright (C) 2014 Marvell
3  * Author: Gregory CLEMENT <gregory.clement@free-electrons.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * version 2 as published by the Free Software Foundation.
8  */
9 
10 #include <linux/io.h>
11 #include <linux/mbus.h>
12 #include <linux/of.h>
13 #include <linux/platform_device.h>
14 
15 #include "xhci-mvebu.h"
16 
17 #define USB3_MAX_WINDOWS	4
18 #define USB3_WIN_CTRL(w)	(0x0 + ((w) * 8))
19 #define USB3_WIN_BASE(w)	(0x4 + ((w) * 8))
20 
21 static void xhci_mvebu_mbus_config(void __iomem *base,
22 			const struct mbus_dram_target_info *dram)
23 {
24 	int win;
25 
26 	/* Clear all existing windows */
27 	for (win = 0; win < USB3_MAX_WINDOWS; win++) {
28 		writel(0, base + USB3_WIN_CTRL(win));
29 		writel(0, base + USB3_WIN_BASE(win));
30 	}
31 
32 	/* Program each DRAM CS in a seperate window */
33 	for (win = 0; win < dram->num_cs; win++) {
34 		const struct mbus_dram_window *cs = dram->cs + win;
35 
36 		writel(((cs->size - 1) & 0xffff0000) | (cs->mbus_attr << 8) |
37 		       (dram->mbus_dram_target_id << 4) | 1,
38 		       base + USB3_WIN_CTRL(win));
39 
40 		writel((cs->base & 0xffff0000), base + USB3_WIN_BASE(win));
41 	}
42 }
43 
44 int xhci_mvebu_mbus_init_quirk(struct platform_device *pdev)
45 {
46 	struct resource	*res;
47 	void __iomem *base;
48 	const struct mbus_dram_target_info *dram;
49 
50 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
51 	if (!res)
52 		return -ENODEV;
53 
54 	/*
55 	 * We don't use devm_ioremap() because this mapping should
56 	 * only exists for the duration of this probe function.
57 	 */
58 	base = ioremap(res->start, resource_size(res));
59 	if (!base)
60 		return -ENODEV;
61 
62 	dram = mv_mbus_dram_info();
63 	xhci_mvebu_mbus_config(base, dram);
64 
65 	/*
66 	 * This memory area was only needed to configure the MBus
67 	 * windows, and is therefore no longer useful.
68 	 */
69 	iounmap(base);
70 
71 	return 0;
72 }
73