xref: /openbmc/linux/drivers/usb/host/xhci-mvebu.c (revision addee42a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2014 Marvell
4  * Author: Gregory CLEMENT <gregory.clement@free-electrons.com>
5  */
6 
7 #include <linux/io.h>
8 #include <linux/mbus.h>
9 #include <linux/of.h>
10 #include <linux/platform_device.h>
11 
12 #include <linux/usb.h>
13 #include <linux/usb/hcd.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 usb_hcd *hcd)
45 {
46 	struct device *dev = hcd->self.controller;
47 	struct platform_device *pdev = to_platform_device(dev);
48 	struct resource	*res;
49 	void __iomem *base;
50 	const struct mbus_dram_target_info *dram;
51 
52 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
53 	if (!res)
54 		return -ENODEV;
55 
56 	/*
57 	 * We don't use devm_ioremap() because this mapping should
58 	 * only exists for the duration of this probe function.
59 	 */
60 	base = ioremap(res->start, resource_size(res));
61 	if (!base)
62 		return -ENODEV;
63 
64 	dram = mv_mbus_dram_info();
65 	xhci_mvebu_mbus_config(base, dram);
66 
67 	/*
68 	 * This memory area was only needed to configure the MBus
69 	 * windows, and is therefore no longer useful.
70 	 */
71 	iounmap(base);
72 
73 	return 0;
74 }
75