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authorHeiko Stuebner <heiko.stuebner@theobroma-systems.com>2021-06-10 23:29:35 +0200
committerVinod Koul <vkoul@kernel.org>2021-06-21 05:56:13 +0200
commitbd1f775d6027810d366600e2490a2ff247e3466e (patch)
treeeff0a4bc968e326efa68c7487e117a306f7a56de /drivers/phy
parentdt-bindings: phy: add yaml binding for rockchip-inno-csi-dphy (diff)
downloadlinux-bd1f775d6027810d366600e2490a2ff247e3466e.tar.xz
linux-bd1f775d6027810d366600e2490a2ff247e3466e.zip
phy/rockchip: add Innosilicon-based CSI dphy
The CSI dphy found for example on the rk3326/px30 and rk3368 is based on an IP design from Innosilicon. Add a driver for it. Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com> Link: https://lore.kernel.org/r/20210610212935.3520341-3-heiko@sntech.de Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/phy')
-rw-r--r--drivers/phy/rockchip/Kconfig9
-rw-r--r--drivers/phy/rockchip/Makefile1
-rw-r--r--drivers/phy/rockchip/phy-rockchip-inno-csidphy.c459
3 files changed, 469 insertions, 0 deletions
diff --git a/drivers/phy/rockchip/Kconfig b/drivers/phy/rockchip/Kconfig
index 159285f42e5c..e812adad7242 100644
--- a/drivers/phy/rockchip/Kconfig
+++ b/drivers/phy/rockchip/Kconfig
@@ -48,6 +48,15 @@ config PHY_ROCKCHIP_INNO_USB2
help
Support for Rockchip USB2.0 PHY with Innosilicon IP block.
+config PHY_ROCKCHIP_INNO_CSIDPHY
+ tristate "Rockchip Innosilicon MIPI CSI PHY driver"
+ depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+ select GENERIC_PHY
+ select GENERIC_PHY_MIPI_DPHY
+ help
+ Enable this to support the Rockchip MIPI CSI PHY with
+ Innosilicon IP block.
+
config PHY_ROCKCHIP_INNO_DSIDPHY
tristate "Rockchip Innosilicon MIPI/LVDS/TTL PHY driver"
depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
diff --git a/drivers/phy/rockchip/Makefile b/drivers/phy/rockchip/Makefile
index c3cfc7f0af5c..f0eec212b2aa 100644
--- a/drivers/phy/rockchip/Makefile
+++ b/drivers/phy/rockchip/Makefile
@@ -2,6 +2,7 @@
obj-$(CONFIG_PHY_ROCKCHIP_DP) += phy-rockchip-dp.o
obj-$(CONFIG_PHY_ROCKCHIP_DPHY_RX0) += phy-rockchip-dphy-rx0.o
obj-$(CONFIG_PHY_ROCKCHIP_EMMC) += phy-rockchip-emmc.o
+obj-$(CONFIG_PHY_ROCKCHIP_INNO_CSIDPHY) += phy-rockchip-inno-csidphy.o
obj-$(CONFIG_PHY_ROCKCHIP_INNO_DSIDPHY) += phy-rockchip-inno-dsidphy.o
obj-$(CONFIG_PHY_ROCKCHIP_INNO_HDMI) += phy-rockchip-inno-hdmi.o
obj-$(CONFIG_PHY_ROCKCHIP_INNO_USB2) += phy-rockchip-inno-usb2.o
diff --git a/drivers/phy/rockchip/phy-rockchip-inno-csidphy.c b/drivers/phy/rockchip/phy-rockchip-inno-csidphy.c
new file mode 100644
index 000000000000..ca13a604ab4f
--- /dev/null
+++ b/drivers/phy/rockchip/phy-rockchip-inno-csidphy.c
@@ -0,0 +1,459 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Rockchip MIPI RX Innosilicon DPHY driver
+ *
+ * Copyright (C) 2021 Fuzhou Rockchip Electronics Co., Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/phy/phy.h>
+#include <linux/phy/phy-mipi-dphy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+/* GRF */
+#define RK1808_GRF_PD_VI_CON_OFFSET 0x0430
+
+#define RK3326_GRF_PD_VI_CON_OFFSET 0x0430
+
+#define RK3368_GRF_SOC_CON6_OFFSET 0x0418
+
+/* PHY */
+#define CSIDPHY_CTRL_LANE_ENABLE 0x00
+#define CSIDPHY_CTRL_LANE_ENABLE_CK BIT(6)
+#define CSIDPHY_CTRL_LANE_ENABLE_MASK GENMASK(5, 2)
+#define CSIDPHY_CTRL_LANE_ENABLE_UNDEFINED BIT(0)
+
+/* not present on all variants */
+#define CSIDPHY_CTRL_PWRCTL 0x04
+#define CSIDPHY_CTRL_PWRCTL_UNDEFINED GENMASK(7, 5)
+#define CSIDPHY_CTRL_PWRCTL_SYNCRST BIT(2)
+#define CSIDPHY_CTRL_PWRCTL_LDO_PD BIT(1)
+#define CSIDPHY_CTRL_PWRCTL_PLL_PD BIT(0)
+
+#define CSIDPHY_CTRL_DIG_RST 0x80
+#define CSIDPHY_CTRL_DIG_RST_UNDEFINED 0x1e
+#define CSIDPHY_CTRL_DIG_RST_RESET BIT(0)
+
+/* offset after ths_settle_offset */
+#define CSIDPHY_CLK_THS_SETTLE 0
+#define CSIDPHY_LANE_THS_SETTLE(n) (((n) + 1) * 0x80)
+#define CSIDPHY_THS_SETTLE_MASK GENMASK(6, 0)
+
+/* offset after calib_offset */
+#define CSIDPHY_CLK_CALIB_EN 0
+#define CSIDPHY_LANE_CALIB_EN(n) (((n) + 1) * 0x80)
+#define CSIDPHY_CALIB_EN BIT(7)
+
+/* Configure the count time of the THS-SETTLE by protocol. */
+#define RK1808_CSIDPHY_CLK_WR_THS_SETTLE 0x160
+#define RK3326_CSIDPHY_CLK_WR_THS_SETTLE 0x100
+#define RK3368_CSIDPHY_CLK_WR_THS_SETTLE 0x100
+
+/* Calibration reception enable */
+#define RK1808_CSIDPHY_CLK_CALIB_EN 0x168
+
+/*
+ * The higher 16-bit of this register is used for write protection
+ * only if BIT(x + 16) set to 1 the BIT(x) can be written.
+ */
+#define HIWORD_UPDATE(val, mask, shift) \
+ ((val) << (shift) | (mask) << ((shift) + 16))
+
+#define HZ_TO_MHZ(freq) div_u64(freq, 1000 * 1000)
+
+enum dphy_reg_id {
+ /* rk1808 & rk3326 */
+ GRF_DPHY_CSIPHY_FORCERXMODE,
+ GRF_DPHY_CSIPHY_CLKLANE_EN,
+ GRF_DPHY_CSIPHY_DATALANE_EN,
+};
+
+struct dphy_reg {
+ u32 offset;
+ u32 mask;
+ u32 shift;
+};
+
+#define PHY_REG(_offset, _width, _shift) \
+ { .offset = _offset, .mask = BIT(_width) - 1, .shift = _shift, }
+
+static const struct dphy_reg rk1808_grf_dphy_regs[] = {
+ [GRF_DPHY_CSIPHY_FORCERXMODE] = PHY_REG(RK1808_GRF_PD_VI_CON_OFFSET, 4, 0),
+ [GRF_DPHY_CSIPHY_CLKLANE_EN] = PHY_REG(RK1808_GRF_PD_VI_CON_OFFSET, 1, 8),
+ [GRF_DPHY_CSIPHY_DATALANE_EN] = PHY_REG(RK1808_GRF_PD_VI_CON_OFFSET, 4, 4),
+};
+
+static const struct dphy_reg rk3326_grf_dphy_regs[] = {
+ [GRF_DPHY_CSIPHY_FORCERXMODE] = PHY_REG(RK3326_GRF_PD_VI_CON_OFFSET, 4, 0),
+ [GRF_DPHY_CSIPHY_CLKLANE_EN] = PHY_REG(RK3326_GRF_PD_VI_CON_OFFSET, 1, 8),
+ [GRF_DPHY_CSIPHY_DATALANE_EN] = PHY_REG(RK3326_GRF_PD_VI_CON_OFFSET, 4, 4),
+};
+
+static const struct dphy_reg rk3368_grf_dphy_regs[] = {
+ [GRF_DPHY_CSIPHY_FORCERXMODE] = PHY_REG(RK3368_GRF_SOC_CON6_OFFSET, 4, 8),
+};
+
+struct hsfreq_range {
+ u32 range_h;
+ u8 cfg_bit;
+};
+
+struct dphy_drv_data {
+ int pwrctl_offset;
+ int ths_settle_offset;
+ int calib_offset;
+ const struct hsfreq_range *hsfreq_ranges;
+ int num_hsfreq_ranges;
+ const struct dphy_reg *grf_regs;
+};
+
+struct rockchip_inno_csidphy {
+ struct device *dev;
+ void __iomem *phy_base;
+ struct clk *pclk;
+ struct regmap *grf;
+ struct reset_control *rst;
+ const struct dphy_drv_data *drv_data;
+ struct phy_configure_opts_mipi_dphy config;
+ u8 hsfreq;
+};
+
+static inline void write_grf_reg(struct rockchip_inno_csidphy *priv,
+ int index, u8 value)
+{
+ const struct dphy_drv_data *drv_data = priv->drv_data;
+ const struct dphy_reg *reg = &drv_data->grf_regs[index];
+
+ if (reg->offset)
+ regmap_write(priv->grf, reg->offset,
+ HIWORD_UPDATE(value, reg->mask, reg->shift));
+}
+
+/* These tables must be sorted by .range_h ascending. */
+static const struct hsfreq_range rk1808_mipidphy_hsfreq_ranges[] = {
+ { 109, 0x02}, { 149, 0x03}, { 199, 0x06}, { 249, 0x06},
+ { 299, 0x06}, { 399, 0x08}, { 499, 0x0b}, { 599, 0x0e},
+ { 699, 0x10}, { 799, 0x12}, { 999, 0x16}, {1199, 0x1e},
+ {1399, 0x23}, {1599, 0x2d}, {1799, 0x32}, {1999, 0x37},
+ {2199, 0x3c}, {2399, 0x41}, {2499, 0x46}
+};
+
+static const struct hsfreq_range rk3326_mipidphy_hsfreq_ranges[] = {
+ { 109, 0x00}, { 149, 0x01}, { 199, 0x02}, { 249, 0x03},
+ { 299, 0x04}, { 399, 0x05}, { 499, 0x06}, { 599, 0x07},
+ { 699, 0x08}, { 799, 0x09}, { 899, 0x0a}, {1099, 0x0b},
+ {1249, 0x0c}, {1349, 0x0d}, {1500, 0x0e}
+};
+
+static const struct hsfreq_range rk3368_mipidphy_hsfreq_ranges[] = {
+ { 109, 0x00}, { 149, 0x01}, { 199, 0x02}, { 249, 0x03},
+ { 299, 0x04}, { 399, 0x05}, { 499, 0x06}, { 599, 0x07},
+ { 699, 0x08}, { 799, 0x09}, { 899, 0x0a}, {1099, 0x0b},
+ {1249, 0x0c}, {1349, 0x0d}, {1500, 0x0e}
+};
+
+static void rockchip_inno_csidphy_ths_settle(struct rockchip_inno_csidphy *priv,
+ int hsfreq, int offset)
+{
+ const struct dphy_drv_data *drv_data = priv->drv_data;
+ u32 val;
+
+ val = readl(priv->phy_base + drv_data->ths_settle_offset + offset);
+ val &= ~CSIDPHY_THS_SETTLE_MASK;
+ val |= hsfreq;
+ writel(val, priv->phy_base + drv_data->ths_settle_offset + offset);
+}
+
+static int rockchip_inno_csidphy_configure(struct phy *phy,
+ union phy_configure_opts *opts)
+{
+ struct rockchip_inno_csidphy *priv = phy_get_drvdata(phy);
+ const struct dphy_drv_data *drv_data = priv->drv_data;
+ struct phy_configure_opts_mipi_dphy *config = &opts->mipi_dphy;
+ unsigned int hsfreq = 0;
+ unsigned int i;
+ u64 data_rate_mbps;
+ int ret;
+
+ /* pass with phy_mipi_dphy_get_default_config (with pixel rate?) */
+ ret = phy_mipi_dphy_config_validate(config);
+ if (ret)
+ return ret;
+
+ data_rate_mbps = HZ_TO_MHZ(config->hs_clk_rate);
+
+ dev_dbg(priv->dev, "lanes %d - data_rate_mbps %llu\n",
+ config->lanes, data_rate_mbps);
+ for (i = 0; i < drv_data->num_hsfreq_ranges; i++) {
+ if (drv_data->hsfreq_ranges[i].range_h >= data_rate_mbps) {
+ hsfreq = drv_data->hsfreq_ranges[i].cfg_bit;
+ break;
+ }
+ }
+ if (!hsfreq)
+ return -EINVAL;
+
+ priv->hsfreq = hsfreq;
+ priv->config = *config;
+ return 0;
+}
+
+static int rockchip_inno_csidphy_power_on(struct phy *phy)
+{
+ struct rockchip_inno_csidphy *priv = phy_get_drvdata(phy);
+ const struct dphy_drv_data *drv_data = priv->drv_data;
+ u64 data_rate_mbps = HZ_TO_MHZ(priv->config.hs_clk_rate);
+ u32 val;
+ int ret, i;
+
+ ret = clk_enable(priv->pclk);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_resume_and_get(priv->dev);
+ if (ret < 0) {
+ clk_disable(priv->pclk);
+ return ret;
+ }
+
+ /* phy start */
+ if (drv_data->pwrctl_offset >= 0)
+ writel(CSIDPHY_CTRL_PWRCTL_UNDEFINED |
+ CSIDPHY_CTRL_PWRCTL_SYNCRST,
+ priv->phy_base + drv_data->pwrctl_offset);
+
+ /* set data lane num and enable clock lane */
+ val = FIELD_PREP(CSIDPHY_CTRL_LANE_ENABLE_MASK, GENMASK(priv->config.lanes - 1, 0)) |
+ FIELD_PREP(CSIDPHY_CTRL_LANE_ENABLE_CK, 1) |
+ FIELD_PREP(CSIDPHY_CTRL_LANE_ENABLE_UNDEFINED, 1);
+ writel(val, priv->phy_base + CSIDPHY_CTRL_LANE_ENABLE);
+
+ /* Reset dphy analog part */
+ if (drv_data->pwrctl_offset >= 0)
+ writel(CSIDPHY_CTRL_PWRCTL_UNDEFINED,
+ priv->phy_base + drv_data->pwrctl_offset);
+ usleep_range(500, 1000);
+
+ /* Reset dphy digital part */
+ writel(CSIDPHY_CTRL_DIG_RST_UNDEFINED,
+ priv->phy_base + CSIDPHY_CTRL_DIG_RST);
+ writel(CSIDPHY_CTRL_DIG_RST_UNDEFINED + CSIDPHY_CTRL_DIG_RST_RESET,
+ priv->phy_base + CSIDPHY_CTRL_DIG_RST);
+
+ /* not into receive mode/wait stopstate */
+ write_grf_reg(priv, GRF_DPHY_CSIPHY_FORCERXMODE, 0x0);
+
+ /* enable calibration */
+ if (data_rate_mbps > 1500 && drv_data->calib_offset >= 0) {
+ writel(CSIDPHY_CALIB_EN,
+ priv->phy_base + drv_data->calib_offset +
+ CSIDPHY_CLK_CALIB_EN);
+ for (i = 0; i < priv->config.lanes; i++)
+ writel(CSIDPHY_CALIB_EN,
+ priv->phy_base + drv_data->calib_offset +
+ CSIDPHY_LANE_CALIB_EN(i));
+ }
+
+ rockchip_inno_csidphy_ths_settle(priv, priv->hsfreq,
+ CSIDPHY_CLK_THS_SETTLE);
+ for (i = 0; i < priv->config.lanes; i++)
+ rockchip_inno_csidphy_ths_settle(priv, priv->hsfreq,
+ CSIDPHY_LANE_THS_SETTLE(i));
+
+ write_grf_reg(priv, GRF_DPHY_CSIPHY_CLKLANE_EN, 0x1);
+ write_grf_reg(priv, GRF_DPHY_CSIPHY_DATALANE_EN,
+ GENMASK(priv->config.lanes - 1, 0));
+
+ return 0;
+}
+
+static int rockchip_inno_csidphy_power_off(struct phy *phy)
+{
+ struct rockchip_inno_csidphy *priv = phy_get_drvdata(phy);
+ const struct dphy_drv_data *drv_data = priv->drv_data;
+
+ /* disable all lanes */
+ writel(CSIDPHY_CTRL_LANE_ENABLE_UNDEFINED,
+ priv->phy_base + CSIDPHY_CTRL_LANE_ENABLE);
+
+ /* disable pll and ldo */
+ if (drv_data->pwrctl_offset >= 0)
+ writel(CSIDPHY_CTRL_PWRCTL_UNDEFINED |
+ CSIDPHY_CTRL_PWRCTL_LDO_PD |
+ CSIDPHY_CTRL_PWRCTL_PLL_PD,
+ priv->phy_base + drv_data->pwrctl_offset);
+ usleep_range(500, 1000);
+
+ pm_runtime_put(priv->dev);
+ clk_disable(priv->pclk);
+
+ return 0;
+}
+
+static int rockchip_inno_csidphy_init(struct phy *phy)
+{
+ struct rockchip_inno_csidphy *priv = phy_get_drvdata(phy);
+
+ return clk_prepare(priv->pclk);
+}
+
+static int rockchip_inno_csidphy_exit(struct phy *phy)
+{
+ struct rockchip_inno_csidphy *priv = phy_get_drvdata(phy);
+
+ clk_unprepare(priv->pclk);
+
+ return 0;
+}
+
+static const struct phy_ops rockchip_inno_csidphy_ops = {
+ .power_on = rockchip_inno_csidphy_power_on,
+ .power_off = rockchip_inno_csidphy_power_off,
+ .init = rockchip_inno_csidphy_init,
+ .exit = rockchip_inno_csidphy_exit,
+ .configure = rockchip_inno_csidphy_configure,
+ .owner = THIS_MODULE,
+};
+
+static const struct dphy_drv_data rk1808_mipidphy_drv_data = {
+ .pwrctl_offset = -1,
+ .ths_settle_offset = RK1808_CSIDPHY_CLK_WR_THS_SETTLE,
+ .calib_offset = RK1808_CSIDPHY_CLK_CALIB_EN,
+ .hsfreq_ranges = rk1808_mipidphy_hsfreq_ranges,
+ .num_hsfreq_ranges = ARRAY_SIZE(rk1808_mipidphy_hsfreq_ranges),
+ .grf_regs = rk1808_grf_dphy_regs,
+};
+
+static const struct dphy_drv_data rk3326_mipidphy_drv_data = {
+ .pwrctl_offset = CSIDPHY_CTRL_PWRCTL,
+ .ths_settle_offset = RK3326_CSIDPHY_CLK_WR_THS_SETTLE,
+ .calib_offset = -1,
+ .hsfreq_ranges = rk3326_mipidphy_hsfreq_ranges,
+ .num_hsfreq_ranges = ARRAY_SIZE(rk3326_mipidphy_hsfreq_ranges),
+ .grf_regs = rk3326_grf_dphy_regs,
+};
+
+static const struct dphy_drv_data rk3368_mipidphy_drv_data = {
+ .pwrctl_offset = CSIDPHY_CTRL_PWRCTL,
+ .ths_settle_offset = RK3368_CSIDPHY_CLK_WR_THS_SETTLE,
+ .calib_offset = -1,
+ .hsfreq_ranges = rk3368_mipidphy_hsfreq_ranges,
+ .num_hsfreq_ranges = ARRAY_SIZE(rk3368_mipidphy_hsfreq_ranges),
+ .grf_regs = rk3368_grf_dphy_regs,
+};
+
+static const struct of_device_id rockchip_inno_csidphy_match_id[] = {
+ {
+ .compatible = "rockchip,px30-csi-dphy",
+ .data = &rk3326_mipidphy_drv_data,
+ },
+ {
+ .compatible = "rockchip,rk1808-csi-dphy",
+ .data = &rk1808_mipidphy_drv_data,
+ },
+ {
+ .compatible = "rockchip,rk3326-csi-dphy",
+ .data = &rk3326_mipidphy_drv_data,
+ },
+ {
+ .compatible = "rockchip,rk3368-csi-dphy",
+ .data = &rk3368_mipidphy_drv_data,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rockchip_inno_csidphy_match_id);
+
+static int rockchip_inno_csidphy_probe(struct platform_device *pdev)
+{
+ struct rockchip_inno_csidphy *priv;
+ struct device *dev = &pdev->dev;
+ struct phy_provider *phy_provider;
+ struct phy *phy;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+ platform_set_drvdata(pdev, priv);
+
+ priv->drv_data = of_device_get_match_data(dev);
+ if (!priv->drv_data) {
+ dev_err(dev, "Can't find device data\n");
+ return -ENODEV;
+ }
+
+ priv->grf = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "rockchip,grf");
+ if (IS_ERR(priv->grf)) {
+ dev_err(dev, "Can't find GRF syscon\n");
+ return PTR_ERR(priv->grf);
+ }
+
+ priv->phy_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->phy_base))
+ return PTR_ERR(priv->phy_base);
+
+ priv->pclk = devm_clk_get(dev, "pclk");
+ if (IS_ERR(priv->pclk)) {
+ dev_err(dev, "failed to get pclk\n");
+ return PTR_ERR(priv->pclk);
+ }
+
+ priv->rst = devm_reset_control_get(dev, "apb");
+ if (IS_ERR(priv->rst)) {
+ dev_err(dev, "failed to get system reset control\n");
+ return PTR_ERR(priv->rst);
+ }
+
+ phy = devm_phy_create(dev, NULL, &rockchip_inno_csidphy_ops);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create phy\n");
+ return PTR_ERR(phy);
+ }
+
+ phy_set_drvdata(phy, priv);
+
+ phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(phy_provider)) {
+ dev_err(dev, "failed to register phy provider\n");
+ return PTR_ERR(phy_provider);
+ }
+
+ pm_runtime_enable(dev);
+
+ return 0;
+}
+
+static int rockchip_inno_csidphy_remove(struct platform_device *pdev)
+{
+ struct rockchip_inno_csidphy *priv = platform_get_drvdata(pdev);
+
+ pm_runtime_disable(priv->dev);
+
+ return 0;
+}
+
+static struct platform_driver rockchip_inno_csidphy_driver = {
+ .driver = {
+ .name = "rockchip-inno-csidphy",
+ .of_match_table = rockchip_inno_csidphy_match_id,
+ },
+ .probe = rockchip_inno_csidphy_probe,
+ .remove = rockchip_inno_csidphy_remove,
+};
+
+module_platform_driver(rockchip_inno_csidphy_driver);
+MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@theobroma-systems.com>");
+MODULE_DESCRIPTION("Rockchip MIPI Innosilicon CSI-DPHY driver");
+MODULE_LICENSE("GPL v2");