| Message ID | 1470512452-8322-7-git-send-email-mirza.krak@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 06/08/16 20:40, Mirza Krak wrote: > From: Mirza Krak <mirza.krak@gmail.com> > > The Generic Memory Interface bus can be used to connect high-speed > devices such as NOR flash, FPGAs, DSPs... > > Signed-off-by: Mirza Krak <mirza.krak@gmail.com> > --- > drivers/bus/Kconfig | 7 ++ > drivers/bus/Makefile | 1 + > drivers/bus/tegra-gmi.c | 224 ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 232 insertions(+) > create mode 100644 drivers/bus/tegra-gmi.c > > diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig > index 3b205e2..88bbf2c 100644 > --- a/drivers/bus/Kconfig > +++ b/drivers/bus/Kconfig > @@ -145,6 +145,13 @@ config TEGRA_ACONNECT > Driver for the Tegra ACONNECT bus which is used to interface with > the devices inside the Audio Processing Engine (APE) for Tegra210. > > +config TEGRA_GMI > + tristate "Tegra Generic Memory Interface bus driver" > + depends on ARCH_TEGRA > + help > + Driver for the Tegra Generic Memory Interface bus which can be used > + to attach devices such as NOR, UART, FPGA and more. > + > config UNIPHIER_SYSTEM_BUS > tristate "UniPhier System Bus driver" > depends on ARCH_UNIPHIER && OF > diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile > index ac84cc4..34e2bab 100644 > --- a/drivers/bus/Makefile > +++ b/drivers/bus/Makefile > @@ -18,5 +18,6 @@ obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o > obj-$(CONFIG_SUNXI_RSB) += sunxi-rsb.o > obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o > obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o > +obj-$(CONFIG_TEGRA_GMI) += tegra-gmi.o > obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o > obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o > diff --git a/drivers/bus/tegra-gmi.c b/drivers/bus/tegra-gmi.c > new file mode 100644 > index 0000000..7a45442 > --- /dev/null > +++ b/drivers/bus/tegra-gmi.c > @@ -0,0 +1,224 @@ > +/* > + * Driver for NVIDIA Generic Memory Interface > + * > + * Copyright (C) 2016 Host Mobility AB. All rights reserved. > + * > + * This file is licensed under the terms of the GNU General Public > + * License version 2. This program is licensed "as is" without any > + * warranty of any kind, whether express or implied. > + */ > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/reset.h> > + > +#define TEGRA_GMI_CONFIG 0x00 > +#define TEGRA_GMI_CONFIG_GO BIT(31) > +#define TEGRA_GMI_BUS_WIDTH_32BIT BIT(30) > +#define TEGRA_GMI_MUX_MODE BIT(28) > +#define TEGRA_GMI_RDY_BEFORE_DATA BIT(24) > +#define TEGRA_GMI_RDY_ACTIVE_HIGH BIT(23) > +#define TEGRA_GMI_ADV_ACTIVE_HIGH BIT(22) > +#define TEGRA_GMI_OE_ACTIVE_HIGH BIT(21) > +#define TEGRA_GMI_CS_ACTIVE_HIGH BIT(20) > +#define TEGRA_GMI_CS_SELECT(x) ((x & 0x7) << 4) > + > +#define TEGRA_GMI_TIMING0 0x10 > +#define TEGRA_GMI_MUXED_WIDTH(x) ((x & 0xf) << 12) > +#define TEGRA_GMI_HOLD_WIDTH(x) ((x & 0xf) << 8) > +#define TEGRA_GMI_ADV_WIDTH(x) ((x & 0xf) << 4) > +#define TEGRA_GMI_CE_WIDTH(x) (x & 0xf) > + > +#define TEGRA_GMI_TIMING1 0x14 > +#define TEGRA_GMI_WE_WIDTH(x) ((x & 0xff) << 16) > +#define TEGRA_GMI_OE_WIDTH(x) ((x & 0xff) << 8) > +#define TEGRA_GMI_WAIT_WIDTH(x) (x & 0xff) > + > +struct tegra_gmi_priv { > + void __iomem *base; > + > + u32 snor_config; > + u32 snor_timing0; > + u32 snor_timing1; > + > + struct clk *clk; > +}; > + > +static void tegra_gmi_init(struct device *dev, struct tegra_gmi_priv *priv) > +{ > + writel(priv->snor_timing0, priv->base + TEGRA_GMI_TIMING0); > + writel(priv->snor_timing1, priv->base + TEGRA_GMI_TIMING1); > + > + priv->snor_config |= TEGRA_GMI_CONFIG_GO; > + writel(priv->snor_config, priv->base + TEGRA_GMI_CONFIG); > +} > + > +static int tegra_gmi_parse_dt(struct device *dev, struct tegra_gmi_priv *priv) > +{ > + struct device_node *of_node = dev->of_node; > + u32 property; > + > + /* configuration */ > + > + if (of_property_read_bool(of_node, "nvidia,snor-data-width-32bit")) > + priv->snor_config |= TEGRA_GMI_BUS_WIDTH_32BIT; > + > + if (of_property_read_bool(of_node, "nvidia,snor-mux-mode")) > + priv->snor_config |= TEGRA_GMI_MUX_MODE; > + > + if (of_property_read_bool(of_node, "nvidia,snor-rdy-active-before-data")) Line is over 80 characters. > + priv->snor_config |= TEGRA_GMI_RDY_BEFORE_DATA; > + > + if (of_property_read_bool(of_node, "nvidia,snor-rdy-inv")) > + priv->snor_config |= TEGRA_GMI_RDY_ACTIVE_HIGH; > + > + if (of_property_read_bool(of_node, "nvidia,snor-adv-inv")) > + priv->snor_config |= TEGRA_GMI_ADV_ACTIVE_HIGH; > + > + if (of_property_read_bool(of_node, "nvidia,snor-oe-inv")) > + priv->snor_config |= TEGRA_GMI_OE_ACTIVE_HIGH; > + > + if (of_property_read_bool(of_node, "nvidia,snor-cs-inv")) > + priv->snor_config |= TEGRA_GMI_CS_ACTIVE_HIGH; > + > + if (!of_property_read_u32(of_node, "nvidia,snor-cs-select", &property)) > + priv->snor_config |= TEGRA_GMI_CS_SELECT(property); > + > + /* Timing, the default values that are provided are reset values */ > + > + if (!of_property_read_u32(of_node, "nvidia,snor-muxed-width", &property)) Line is over 80 characters. > + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(property); > + else > + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(1); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-hold-width", &property)) > + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(property); > + else > + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(1); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-adv-width", &property)) > + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(property); > + else > + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(1); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-ce-width", &property)) > + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(property); > + else > + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(4); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-we-width", &property)) > + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(property); > + else > + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(1); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-oe-width", &property)) > + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(property); > + else > + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(1); > + > + if (!of_property_read_u32(of_node, "nvidia,snor-wait-width", &property)) > + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(property); > + else > + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(3); > + > + return of_platform_default_populate(of_node, NULL, dev); Seems odd to do this here. Why not as the last thing in probe once the GMI has been setup correctly? > +} > + > +static int tegra_gmi_probe(struct platform_device *pdev) > +{ > + struct resource *res; > + struct clk *clk; > + struct device *dev = &pdev->dev; > + struct reset_control *rst; > + struct tegra_gmi_priv *priv; > + void __iomem *base; > + int ret; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + base = devm_ioremap_resource(dev, res); > + if (IS_ERR(base)) > + return PTR_ERR(base); > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->base = base; If you allocate the memory first, you can get rid of this extra base variable. > + clk = devm_clk_get(dev, "gmi"); > + if (IS_ERR(clk)) { > + dev_err(dev, "can not get clock\n"); > + return PTR_ERR(clk); > + } > + > + priv->clk = clk; Why not set priv->clk directly from calling devm_clk_get? Then you don't this extra clk variable. > + > + rst = devm_reset_control_get(dev, "gmi"); > + if (IS_ERR(rst)) { > + dev_err(dev, "can not get reset\n"); > + return PTR_ERR(rst); > + } > + > + ret = tegra_gmi_parse_dt(dev, priv); > + if (ret) { > + dev_err(dev, "fail to create devices.\n"); > + return ret; > + } > + > + ret = clk_prepare_enable(clk); > + if (ret) { > + dev_err(dev, "fail to enable clock.\n"); > + return ret; > + } > + > + reset_control_assert(rst); > + udelay(2); > + reset_control_deassert(rst); > + > + tegra_gmi_init(dev, priv); > + > + dev_set_drvdata(dev, priv); > + > + return 0; > +} > + > +static int tegra_gmi_remove(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; Do you really need this dev variable? > + struct tegra_gmi_priv *priv = dev_get_drvdata(dev); > + void __iomem *base = priv->base; Do you really need this base variable? > + u32 config; > + > + of_platform_depopulate(dev); > + > + config = readl(base + TEGRA_GMI_CONFIG); > + config &= ~TEGRA_GMI_CONFIG_GO; > + writel(config, base + TEGRA_GMI_CONFIG); > + > + clk_disable_unprepare(priv->clk); What about asserting the reset? > + > + return 0; > +} > + > +static const struct of_device_id tegra_gmi_id_table[] = { > + { .compatible = "nvidia,tegra20-gmi", }, > + { .compatible = "nvidia,tegra30-gmi", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, tegra_gmi_id_table); > + > +static struct platform_driver tegra_gmi_driver = { > + .probe = tegra_gmi_probe, > + .remove = tegra_gmi_remove, > + .driver = { > + .name = "tegra-gmi", > + .of_match_table = tegra_gmi_id_table, > + }, > +}; > +module_platform_driver(tegra_gmi_driver); > + > +MODULE_AUTHOR("Mirza Krak <mirza.krak@gmail.com"); > +MODULE_DESCRIPTION("NVIDIA Tegra GMI Bus Driver"); > +MODULE_LICENSE("GPL v2"); > Cheers Jon
2016-08-08 15:47 GMT+02:00 Jon Hunter <jonathanh@nvidia.com>: > > On 06/08/16 20:40, Mirza Krak wrote: >> From: Mirza Krak <mirza.krak@gmail.com> >> >> The Generic Memory Interface bus can be used to connect high-speed >> devices such as NOR flash, FPGAs, DSPs... >> >> Signed-off-by: Mirza Krak <mirza.krak@gmail.com> >> --- >> drivers/bus/Kconfig | 7 ++ >> drivers/bus/Makefile | 1 + >> drivers/bus/tegra-gmi.c | 224 ++++++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 232 insertions(+) >> create mode 100644 drivers/bus/tegra-gmi.c >> <--snip--> >> + >> +static int tegra_gmi_parse_dt(struct device *dev, struct tegra_gmi_priv *priv) >> +{ >> + struct device_node *of_node = dev->of_node; >> + u32 property; >> + >> + /* configuration */ >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-data-width-32bit")) >> + priv->snor_config |= TEGRA_GMI_BUS_WIDTH_32BIT; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-mux-mode")) >> + priv->snor_config |= TEGRA_GMI_MUX_MODE; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-rdy-active-before-data")) > > Line is over 80 characters. Yes, indeed it is. I ran checkpatch on everything and did get warnings about it being over 80 characters. But scratched my head a bit of why it complained because it was not over 80 characters in my editor. But now I know why. My tab size was set to 4, and then it is not over 80 :). > >> + priv->snor_config |= TEGRA_GMI_RDY_BEFORE_DATA; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-rdy-inv")) >> + priv->snor_config |= TEGRA_GMI_RDY_ACTIVE_HIGH; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-adv-inv")) >> + priv->snor_config |= TEGRA_GMI_ADV_ACTIVE_HIGH; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-oe-inv")) >> + priv->snor_config |= TEGRA_GMI_OE_ACTIVE_HIGH; >> + >> + if (of_property_read_bool(of_node, "nvidia,snor-cs-inv")) >> + priv->snor_config |= TEGRA_GMI_CS_ACTIVE_HIGH; >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-cs-select", &property)) >> + priv->snor_config |= TEGRA_GMI_CS_SELECT(property); >> + >> + /* Timing, the default values that are provided are reset values */ >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-muxed-width", &property)) > > Line is over 80 characters. ACK. > >> + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(property); >> + else >> + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(1); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-hold-width", &property)) >> + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(property); >> + else >> + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(1); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-adv-width", &property)) >> + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(property); >> + else >> + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(1); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-ce-width", &property)) >> + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(property); >> + else >> + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(4); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-we-width", &property)) >> + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(property); >> + else >> + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(1); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-oe-width", &property)) >> + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(property); >> + else >> + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(1); >> + >> + if (!of_property_read_u32(of_node, "nvidia,snor-wait-width", &property)) >> + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(property); >> + else >> + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(3); >> + >> + return of_platform_default_populate(of_node, NULL, dev); > > Seems odd to do this here. Why not as the last thing in probe once the > GMI has been setup correctly? It is done here mostly to avoid clean up in probe. I could move it out of tegra_gmi_parse_dt and put it right after that call but still before clk enable? Is that less odd? > >> +} >> + >> +static int tegra_gmi_probe(struct platform_device *pdev) >> +{ >> + struct resource *res; >> + struct clk *clk; >> + struct device *dev = &pdev->dev; >> + struct reset_control *rst; >> + struct tegra_gmi_priv *priv; >> + void __iomem *base; >> + int ret; >> + >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + base = devm_ioremap_resource(dev, res); >> + if (IS_ERR(base)) >> + return PTR_ERR(base); >> + >> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); >> + if (!priv) >> + return -ENOMEM; >> + >> + priv->base = base; > > If you allocate the memory first, you can get rid of this extra base > variable. ACK. > >> + clk = devm_clk_get(dev, "gmi"); >> + if (IS_ERR(clk)) { >> + dev_err(dev, "can not get clock\n"); >> + return PTR_ERR(clk); >> + } >> + >> + priv->clk = clk; > > Why not set priv->clk directly from calling devm_clk_get? Then you don't > this extra clk variable. ACK. > >> + >> + rst = devm_reset_control_get(dev, "gmi"); >> + if (IS_ERR(rst)) { >> + dev_err(dev, "can not get reset\n"); >> + return PTR_ERR(rst); >> + } >> + >> + ret = tegra_gmi_parse_dt(dev, priv); >> + if (ret) { >> + dev_err(dev, "fail to create devices.\n"); >> + return ret; >> + } >> + >> + ret = clk_prepare_enable(clk); >> + if (ret) { >> + dev_err(dev, "fail to enable clock.\n"); >> + return ret; >> + } >> + >> + reset_control_assert(rst); >> + udelay(2); >> + reset_control_deassert(rst); >> + >> + tegra_gmi_init(dev, priv); >> + >> + dev_set_drvdata(dev, priv); >> + >> + return 0; >> +} >> + >> +static int tegra_gmi_remove(struct platform_device *pdev) >> +{ >> + struct device *dev = &pdev->dev; > > Do you really need this dev variable? Not really. > >> + struct tegra_gmi_priv *priv = dev_get_drvdata(dev); >> + void __iomem *base = priv->base; > > Do you really need this base variable? Not really, > >> + u32 config; >> + >> + of_platform_depopulate(dev); >> + >> + config = readl(base + TEGRA_GMI_CONFIG); >> + config &= ~TEGRA_GMI_CONFIG_GO; >> + writel(config, base + TEGRA_GMI_CONFIG); >> + >> + clk_disable_unprepare(priv->clk); > > What about asserting the reset? ACK, will add that. Best Regards Mirza -- To unsubscribe from this list: send the line "unsubscribe linux-clk" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/08/16 08:21, Mirza Krak wrote: > 2016-08-08 15:47 GMT+02:00 Jon Hunter <jonathanh@nvidia.com>: ... >>> + return of_platform_default_populate(of_node, NULL, dev); >> >> Seems odd to do this here. Why not as the last thing in probe once the >> GMI has been setup correctly? > > It is done here mostly to avoid clean up in probe. I could move it out > of tegra_gmi_parse_dt and put it right after that call but still > before clk enable? Is that less odd? I would have thought that clocks should be enabled and resets de-asserted before we even attempt to populate any children. Hence, I would do this last. Yes that will require some clean-up in probe if this does fail but seems safest. Cheers Jon
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index 3b205e2..88bbf2c 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -145,6 +145,13 @@ config TEGRA_ACONNECT Driver for the Tegra ACONNECT bus which is used to interface with the devices inside the Audio Processing Engine (APE) for Tegra210. +config TEGRA_GMI + tristate "Tegra Generic Memory Interface bus driver" + depends on ARCH_TEGRA + help + Driver for the Tegra Generic Memory Interface bus which can be used + to attach devices such as NOR, UART, FPGA and more. + config UNIPHIER_SYSTEM_BUS tristate "UniPhier System Bus driver" depends on ARCH_UNIPHIER && OF diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile index ac84cc4..34e2bab 100644 --- a/drivers/bus/Makefile +++ b/drivers/bus/Makefile @@ -18,5 +18,6 @@ obj-$(CONFIG_OMAP_OCP2SCP) += omap-ocp2scp.o obj-$(CONFIG_SUNXI_RSB) += sunxi-rsb.o obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o +obj-$(CONFIG_TEGRA_GMI) += tegra-gmi.o obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o diff --git a/drivers/bus/tegra-gmi.c b/drivers/bus/tegra-gmi.c new file mode 100644 index 0000000..7a45442 --- /dev/null +++ b/drivers/bus/tegra-gmi.c @@ -0,0 +1,224 @@ +/* + * Driver for NVIDIA Generic Memory Interface + * + * Copyright (C) 2016 Host Mobility AB. All rights reserved. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/reset.h> + +#define TEGRA_GMI_CONFIG 0x00 +#define TEGRA_GMI_CONFIG_GO BIT(31) +#define TEGRA_GMI_BUS_WIDTH_32BIT BIT(30) +#define TEGRA_GMI_MUX_MODE BIT(28) +#define TEGRA_GMI_RDY_BEFORE_DATA BIT(24) +#define TEGRA_GMI_RDY_ACTIVE_HIGH BIT(23) +#define TEGRA_GMI_ADV_ACTIVE_HIGH BIT(22) +#define TEGRA_GMI_OE_ACTIVE_HIGH BIT(21) +#define TEGRA_GMI_CS_ACTIVE_HIGH BIT(20) +#define TEGRA_GMI_CS_SELECT(x) ((x & 0x7) << 4) + +#define TEGRA_GMI_TIMING0 0x10 +#define TEGRA_GMI_MUXED_WIDTH(x) ((x & 0xf) << 12) +#define TEGRA_GMI_HOLD_WIDTH(x) ((x & 0xf) << 8) +#define TEGRA_GMI_ADV_WIDTH(x) ((x & 0xf) << 4) +#define TEGRA_GMI_CE_WIDTH(x) (x & 0xf) + +#define TEGRA_GMI_TIMING1 0x14 +#define TEGRA_GMI_WE_WIDTH(x) ((x & 0xff) << 16) +#define TEGRA_GMI_OE_WIDTH(x) ((x & 0xff) << 8) +#define TEGRA_GMI_WAIT_WIDTH(x) (x & 0xff) + +struct tegra_gmi_priv { + void __iomem *base; + + u32 snor_config; + u32 snor_timing0; + u32 snor_timing1; + + struct clk *clk; +}; + +static void tegra_gmi_init(struct device *dev, struct tegra_gmi_priv *priv) +{ + writel(priv->snor_timing0, priv->base + TEGRA_GMI_TIMING0); + writel(priv->snor_timing1, priv->base + TEGRA_GMI_TIMING1); + + priv->snor_config |= TEGRA_GMI_CONFIG_GO; + writel(priv->snor_config, priv->base + TEGRA_GMI_CONFIG); +} + +static int tegra_gmi_parse_dt(struct device *dev, struct tegra_gmi_priv *priv) +{ + struct device_node *of_node = dev->of_node; + u32 property; + + /* configuration */ + + if (of_property_read_bool(of_node, "nvidia,snor-data-width-32bit")) + priv->snor_config |= TEGRA_GMI_BUS_WIDTH_32BIT; + + if (of_property_read_bool(of_node, "nvidia,snor-mux-mode")) + priv->snor_config |= TEGRA_GMI_MUX_MODE; + + if (of_property_read_bool(of_node, "nvidia,snor-rdy-active-before-data")) + priv->snor_config |= TEGRA_GMI_RDY_BEFORE_DATA; + + if (of_property_read_bool(of_node, "nvidia,snor-rdy-inv")) + priv->snor_config |= TEGRA_GMI_RDY_ACTIVE_HIGH; + + if (of_property_read_bool(of_node, "nvidia,snor-adv-inv")) + priv->snor_config |= TEGRA_GMI_ADV_ACTIVE_HIGH; + + if (of_property_read_bool(of_node, "nvidia,snor-oe-inv")) + priv->snor_config |= TEGRA_GMI_OE_ACTIVE_HIGH; + + if (of_property_read_bool(of_node, "nvidia,snor-cs-inv")) + priv->snor_config |= TEGRA_GMI_CS_ACTIVE_HIGH; + + if (!of_property_read_u32(of_node, "nvidia,snor-cs-select", &property)) + priv->snor_config |= TEGRA_GMI_CS_SELECT(property); + + /* Timing, the default values that are provided are reset values */ + + if (!of_property_read_u32(of_node, "nvidia,snor-muxed-width", &property)) + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(property); + else + priv->snor_timing0 |= TEGRA_GMI_MUXED_WIDTH(1); + + if (!of_property_read_u32(of_node, "nvidia,snor-hold-width", &property)) + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(property); + else + priv->snor_timing0 |= TEGRA_GMI_HOLD_WIDTH(1); + + if (!of_property_read_u32(of_node, "nvidia,snor-adv-width", &property)) + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(property); + else + priv->snor_timing0 |= TEGRA_GMI_ADV_WIDTH(1); + + if (!of_property_read_u32(of_node, "nvidia,snor-ce-width", &property)) + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(property); + else + priv->snor_timing0 |= TEGRA_GMI_CE_WIDTH(4); + + if (!of_property_read_u32(of_node, "nvidia,snor-we-width", &property)) + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(property); + else + priv->snor_timing1 |= TEGRA_GMI_WE_WIDTH(1); + + if (!of_property_read_u32(of_node, "nvidia,snor-oe-width", &property)) + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(property); + else + priv->snor_timing1 |= TEGRA_GMI_OE_WIDTH(1); + + if (!of_property_read_u32(of_node, "nvidia,snor-wait-width", &property)) + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(property); + else + priv->snor_timing1 |= TEGRA_GMI_WAIT_WIDTH(3); + + return of_platform_default_populate(of_node, NULL, dev); +} + +static int tegra_gmi_probe(struct platform_device *pdev) +{ + struct resource *res; + struct clk *clk; + struct device *dev = &pdev->dev; + struct reset_control *rst; + struct tegra_gmi_priv *priv; + void __iomem *base; + int ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = base; + + clk = devm_clk_get(dev, "gmi"); + if (IS_ERR(clk)) { + dev_err(dev, "can not get clock\n"); + return PTR_ERR(clk); + } + + priv->clk = clk; + + rst = devm_reset_control_get(dev, "gmi"); + if (IS_ERR(rst)) { + dev_err(dev, "can not get reset\n"); + return PTR_ERR(rst); + } + + ret = tegra_gmi_parse_dt(dev, priv); + if (ret) { + dev_err(dev, "fail to create devices.\n"); + return ret; + } + + ret = clk_prepare_enable(clk); + if (ret) { + dev_err(dev, "fail to enable clock.\n"); + return ret; + } + + reset_control_assert(rst); + udelay(2); + reset_control_deassert(rst); + + tegra_gmi_init(dev, priv); + + dev_set_drvdata(dev, priv); + + return 0; +} + +static int tegra_gmi_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct tegra_gmi_priv *priv = dev_get_drvdata(dev); + void __iomem *base = priv->base; + u32 config; + + of_platform_depopulate(dev); + + config = readl(base + TEGRA_GMI_CONFIG); + config &= ~TEGRA_GMI_CONFIG_GO; + writel(config, base + TEGRA_GMI_CONFIG); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static const struct of_device_id tegra_gmi_id_table[] = { + { .compatible = "nvidia,tegra20-gmi", }, + { .compatible = "nvidia,tegra30-gmi", }, + { } +}; +MODULE_DEVICE_TABLE(of, tegra_gmi_id_table); + +static struct platform_driver tegra_gmi_driver = { + .probe = tegra_gmi_probe, + .remove = tegra_gmi_remove, + .driver = { + .name = "tegra-gmi", + .of_match_table = tegra_gmi_id_table, + }, +}; +module_platform_driver(tegra_gmi_driver); + +MODULE_AUTHOR("Mirza Krak <mirza.krak@gmail.com"); +MODULE_DESCRIPTION("NVIDIA Tegra GMI Bus Driver"); +MODULE_LICENSE("GPL v2");