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Note: File does not exist in v3.1.
  1/*
  2 * Copyright (C) STMicroelectronics SA 2014
  3 * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
  4 * License terms:  GNU General Public License (GPL), version 2
  5 */
  6
  7#include <linux/clk.h>
  8#include <linux/io.h>
  9#include <linux/module.h>
 10#include <linux/of.h>
 11#include <linux/platform_device.h>
 12
 13#include <drm/drmP.h>
 14
 15#include "sti_drv.h"
 16
 17/* registers offset */
 18#define VTAC_CONFIG                     0x00
 19#define VTAC_RX_FIFO_CONFIG             0x04
 20#define VTAC_FIFO_CONFIG_VAL            0x04
 21
 22#define VTAC_SYS_CFG8521                0x824
 23#define VTAC_SYS_CFG8522                0x828
 24
 25/* Number of phyts per pixel */
 26#define VTAC_2_5_PPP                    0x0005
 27#define VTAC_3_PPP                      0x0006
 28#define VTAC_4_PPP                      0x0008
 29#define VTAC_5_PPP                      0x000A
 30#define VTAC_6_PPP                      0x000C
 31#define VTAC_13_PPP                     0x001A
 32#define VTAC_14_PPP                     0x001C
 33#define VTAC_15_PPP                     0x001E
 34#define VTAC_16_PPP                     0x0020
 35#define VTAC_17_PPP                     0x0022
 36#define VTAC_18_PPP                     0x0024
 37
 38/* enable bits */
 39#define VTAC_ENABLE                     0x3003
 40
 41#define VTAC_TX_PHY_ENABLE_CLK_PHY      BIT(0)
 42#define VTAC_TX_PHY_ENABLE_CLK_DLL      BIT(1)
 43#define VTAC_TX_PHY_PLL_NOT_OSC_MODE    BIT(3)
 44#define VTAC_TX_PHY_RST_N_DLL_SWITCH    BIT(4)
 45#define VTAC_TX_PHY_PROG_N3             BIT(9)
 46
 47
 48/**
 49 * VTAC mode structure
 50 *
 51 * @vid_in_width: Video Data Resolution
 52 * @phyts_width: Width of phyt buses(phyt low and phyt high).
 53 * @phyts_per_pixel: Number of phyts sent per pixel
 54 */
 55struct sti_vtac_mode {
 56	u32 vid_in_width;
 57	u32 phyts_width;
 58	u32 phyts_per_pixel;
 59};
 60
 61static const struct sti_vtac_mode vtac_mode_main = {
 62	.vid_in_width = 0x2,
 63	.phyts_width = 0x2,
 64	.phyts_per_pixel = VTAC_5_PPP,
 65};
 66static const struct sti_vtac_mode vtac_mode_aux = {
 67	.vid_in_width = 0x1,
 68	.phyts_width = 0x0,
 69	.phyts_per_pixel = VTAC_17_PPP,
 70};
 71
 72/**
 73 * VTAC structure
 74 *
 75 * @dev: pointer to device structure
 76 * @regs: ioremapped registers for RX and TX devices
 77 * @phy_regs: phy registers for TX device
 78 * @clk: clock
 79 * @mode: main or auxillary configuration mode
 80 */
 81struct sti_vtac {
 82	struct device *dev;
 83	void __iomem *regs;
 84	void __iomem *phy_regs;
 85	struct clk *clk;
 86	const struct sti_vtac_mode *mode;
 87};
 88
 89static void sti_vtac_rx_set_config(struct sti_vtac *vtac)
 90{
 91	u32 config;
 92
 93	/* Enable VTAC clock */
 94	if (clk_prepare_enable(vtac->clk))
 95		DRM_ERROR("Failed to prepare/enable vtac_rx clock.\n");
 96
 97	writel(VTAC_FIFO_CONFIG_VAL, vtac->regs + VTAC_RX_FIFO_CONFIG);
 98
 99	config = VTAC_ENABLE;
100	config |= vtac->mode->vid_in_width << 4;
101	config |= vtac->mode->phyts_width << 16;
102	config |= vtac->mode->phyts_per_pixel << 23;
103	writel(config, vtac->regs + VTAC_CONFIG);
104}
105
106static void sti_vtac_tx_set_config(struct sti_vtac *vtac)
107{
108	u32 phy_config;
109	u32 config;
110
111	/* Enable VTAC clock */
112	if (clk_prepare_enable(vtac->clk))
113		DRM_ERROR("Failed to prepare/enable vtac_tx clock.\n");
114
115	/* Configure vtac phy */
116	phy_config = 0x00000000;
117	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8522);
118	phy_config = VTAC_TX_PHY_ENABLE_CLK_PHY;
119	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
120	phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
121	phy_config |= VTAC_TX_PHY_PROG_N3;
122	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
123	phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
124	phy_config |= VTAC_TX_PHY_ENABLE_CLK_DLL;
125	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
126	phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
127	phy_config |= VTAC_TX_PHY_RST_N_DLL_SWITCH;
128	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
129	phy_config = readl(vtac->phy_regs + VTAC_SYS_CFG8521);
130	phy_config |= VTAC_TX_PHY_PLL_NOT_OSC_MODE;
131	writel(phy_config, vtac->phy_regs + VTAC_SYS_CFG8521);
132
133	/* Configure vtac tx */
134	config = VTAC_ENABLE;
135	config |= vtac->mode->vid_in_width << 4;
136	config |= vtac->mode->phyts_width << 16;
137	config |= vtac->mode->phyts_per_pixel << 23;
138	writel(config, vtac->regs + VTAC_CONFIG);
139}
140
141static const struct of_device_id vtac_of_match[] = {
142	{
143		.compatible = "st,vtac-main",
144		.data = &vtac_mode_main,
145	}, {
146		.compatible = "st,vtac-aux",
147		.data = &vtac_mode_aux,
148	}, {
149		/* end node */
150	}
151};
152MODULE_DEVICE_TABLE(of, vtac_of_match);
153
154static int sti_vtac_probe(struct platform_device *pdev)
155{
156	struct device *dev = &pdev->dev;
157	struct device_node *np = dev->of_node;
158	const struct of_device_id *id;
159	struct sti_vtac *vtac;
160	struct resource *res;
161
162	vtac = devm_kzalloc(dev, sizeof(*vtac), GFP_KERNEL);
163	if (!vtac)
164		return -ENOMEM;
165
166	vtac->dev = dev;
167
168	id = of_match_node(vtac_of_match, np);
169	if (!id)
170		return -ENOMEM;
171
172	vtac->mode = id->data;
173
174	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
175	if (!res) {
176		DRM_ERROR("Invalid resource\n");
177		return -ENOMEM;
178	}
179	vtac->regs = devm_ioremap_resource(dev, res);
180	if (IS_ERR(vtac->regs))
181		return PTR_ERR(vtac->regs);
182
183
184	vtac->clk = devm_clk_get(dev, "vtac");
185	if (IS_ERR(vtac->clk)) {
186		DRM_ERROR("Cannot get vtac clock\n");
187		return PTR_ERR(vtac->clk);
188	}
189
190	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
191	if (res) {
192		vtac->phy_regs = devm_ioremap_nocache(dev, res->start,
193						 resource_size(res));
194		sti_vtac_tx_set_config(vtac);
195	} else {
196
197		sti_vtac_rx_set_config(vtac);
198	}
199
200	platform_set_drvdata(pdev, vtac);
201	DRM_INFO("%s %s\n", __func__, dev_name(vtac->dev));
202
203	return 0;
204}
205
206static int sti_vtac_remove(struct platform_device *pdev)
207{
208	return 0;
209}
210
211struct platform_driver sti_vtac_driver = {
212	.driver = {
213		.name = "sti-vtac",
214		.owner = THIS_MODULE,
215		.of_match_table = vtac_of_match,
216	},
217	.probe = sti_vtac_probe,
218	.remove = sti_vtac_remove,
219};
220
221MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
222MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
223MODULE_LICENSE("GPL");