Create the driver for the da8xx master peripheral priority configuration and implement support for writing to the three Master Priority registers on da850 SoCs.
Signed-off-by: Bartosz Golaszewski bgolaszewski@baylibre.com --- .../devicetree/bindings/bus/ti,da850-mstpri.txt | 20 ++ drivers/bus/Kconfig | 9 + drivers/bus/Makefile | 2 + drivers/bus/da8xx-mstpri.c | 266 +++++++++++++++++++++ 4 files changed, 297 insertions(+) create mode 100644 Documentation/devicetree/bindings/bus/ti,da850-mstpri.txt create mode 100644 drivers/bus/da8xx-mstpri.c
diff --git a/Documentation/devicetree/bindings/bus/ti,da850-mstpri.txt b/Documentation/devicetree/bindings/bus/ti,da850-mstpri.txt new file mode 100644 index 0000000..225af09 --- /dev/null +++ b/Documentation/devicetree/bindings/bus/ti,da850-mstpri.txt @@ -0,0 +1,20 @@ +* Device tree bindings for Texas Instruments da8xx master peripheral + priority driver + +DA8XX SoCs feature a set of registers allowing to change the priority of all +peripherals classified as masters. + +Documentation: +OMAP-L138 (DA850) - http://www.ti.com/lit/ug/spruh82c/spruh82c.pdf + +Required properties: + +- compatible: "ti,da850-mstpri", "syscon" - for da850 based boards +- reg: offset and length of the mstpri registers + +Example for da850-lcdk is shown below. + +mstpri { + compatible = "ti,da850-mstpri"; + reg = <0x14110 0x0c>; +}; diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index 7010dca..ed6a89c 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -166,4 +166,13 @@ config VEXPRESS_CONFIG help Platform configuration infrastructure for the ARM Ltd. Versatile Express. + +config DA8XX_MSTPRI + bool "TI da8xx master peripheral priority driver" + depends on ARCH_DAVINCI_DA8XX + help + Driver for Texas Instruments da8xx master peripheral priority + configuration. Allows to adjust the priorities of all master + peripherals. + endmenu diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile index c6cfa6b..2adb540 100644 --- a/drivers/bus/Makefile +++ b/drivers/bus/Makefile @@ -21,3 +21,5 @@ obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o + +obj-$(CONFIG_DA8XX_MSTPRI) += da8xx-mstpri.o diff --git a/drivers/bus/da8xx-mstpri.c b/drivers/bus/da8xx-mstpri.c new file mode 100644 index 0000000..00c4f83 --- /dev/null +++ b/drivers/bus/da8xx-mstpri.c @@ -0,0 +1,266 @@ +/* + * TI da8xx master peripheral priority driver + * + * Copyright (C) 2016 BayLibre SAS + * + * Author: + * Bartosz Golaszewski bgolaszewski@baylibre.com.com + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/regmap.h> +#include <linux/mfd/syscon.h> +#include <linux/of_fdt.h> + +/* + * REVISIT: Linux doesn't have a good framework for the kind of performance + * knobs this driver controls. We can't use device tree properties as it deals + * with hardware configuration rather than description. We also don't want to + * commit to maintaining some random sysfs attributes. + * + * For now we just hardcode the register values for the boards that need + * some changes (as is the case for the LCD controller on da850-lcdk - the + * first board we support here). When linux gets an appropriate framework, + * we'll easily convert the driver to it. + */ + +#define DA8XX_MSTPRI0_OFFSET 0 +#define DA8XX_MSTPRI1_OFFSET 4 +#define DA8XX_MSTPRI2_OFFSET 8 + +enum { + DA8XX_MSTPRI_ARM_I = 0, + DA8XX_MSTPRI_ARM_D, + DA8XX_MSTPRI_UPP, + DA8XX_MSTPRI_SATA, + DA8XX_MSTPRI_PRU0, + DA8XX_MSTPRI_PRU1, + DA8XX_MSTPRI_EDMA30TC0, + DA8XX_MSTPRI_EDMA30TC1, + DA8XX_MSTPRI_EDMA31TC0, + DA8XX_MSTPRI_VPIF_DMA_0, + DA8XX_MSTPRI_VPIF_DMA_1, + DA8XX_MSTPRI_EMAC, + DA8XX_MSTPRI_USB0CFG, + DA8XX_MSTPRI_USB0CDMA, + DA8XX_MSTPRI_UHPI, + DA8XX_MSTPRI_USB1, + DA8XX_MSTPRI_LCDC, +}; + +struct da8xx_mstpri_descr { + int reg; + int shift; + int mask; +}; + +static const struct da8xx_mstpri_descr da8xx_mstpri_priority_list[] = { + [DA8XX_MSTPRI_ARM_I] = { + .reg = DA8XX_MSTPRI0_OFFSET, + .shift = 0, + .mask = 0x0000000f, + }, + [DA8XX_MSTPRI_ARM_D] = { + .reg = DA8XX_MSTPRI0_OFFSET, + .shift = 4, + .mask = 0x000000f0, + }, + [DA8XX_MSTPRI_UPP] = { + .reg = DA8XX_MSTPRI0_OFFSET, + .shift = 16, + .mask = 0x000f0000, + }, + [DA8XX_MSTPRI_SATA] = { + .reg = DA8XX_MSTPRI0_OFFSET, + .shift = 20, + .mask = 0x00f00000, + }, + [DA8XX_MSTPRI_PRU0] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 0, + .mask = 0x0000000f, + }, + [DA8XX_MSTPRI_PRU1] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 4, + .mask = 0x000000f0, + }, + [DA8XX_MSTPRI_EDMA30TC0] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 8, + .mask = 0x00000f00, + }, + [DA8XX_MSTPRI_EDMA30TC1] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 12, + .mask = 0x0000f000, + }, + [DA8XX_MSTPRI_EDMA31TC0] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 16, + .mask = 0x000f0000, + }, + [DA8XX_MSTPRI_VPIF_DMA_0] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 24, + .mask = 0x0f000000, + }, + [DA8XX_MSTPRI_VPIF_DMA_1] = { + .reg = DA8XX_MSTPRI1_OFFSET, + .shift = 28, + .mask = 0xf0000000, + }, + [DA8XX_MSTPRI_EMAC] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 0, + .mask = 0x0000000f, + }, + [DA8XX_MSTPRI_USB0CFG] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 8, + .mask = 0x00000f00, + }, + [DA8XX_MSTPRI_USB0CDMA] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 12, + .mask = 0x0000f000, + }, + [DA8XX_MSTPRI_UHPI] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 20, + .mask = 0x00f00000, + }, + [DA8XX_MSTPRI_USB1] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 24, + .mask = 0x0f000000, + }, + [DA8XX_MSTPRI_LCDC] = { + .reg = DA8XX_MSTPRI2_OFFSET, + .shift = 28, + .mask = 0xf0000000, + }, +}; + +struct da8xx_mstpri_priority { + int which; + u32 val; +}; + +struct da8xx_mstpri_board_priorities { + const char *board; + const struct da8xx_mstpri_priority *priorities; + size_t numprio; +}; + +/* + * Default memory settings of da850 do not meet the throughput/latency + * requirements of tilcdc. This results in the image displayed being + * incorrect and the following warning being displayed by the LCDC + * drm driver: + * + * tilcdc da8xx_lcdc.0: tilcdc_crtc_irq(0x00000020): FIFO underfow + */ +static const struct da8xx_mstpri_priority da850_lcdk_priorities[] = { + { + .which = DA8XX_MSTPRI_LCDC, + .val = 0, + }, + { + .which = DA8XX_MSTPRI_EDMA30TC1, + .val = 0, + }, + { + .which = DA8XX_MSTPRI_EDMA30TC0, + .val = 1, + }, +}; + +static const struct da8xx_mstpri_board_priorities da8xx_mstpri_board_confs[] = { + { + .board = "ti,da850-lcdk", + .priorities = da850_lcdk_priorities, + .numprio = ARRAY_SIZE(da850_lcdk_priorities), + }, +}; + +static const struct da8xx_mstpri_board_priorities * +da8xx_mstpri_get_board_prio(void) +{ + const struct da8xx_mstpri_board_priorities *board_prio; + int i; + + for (i = 0; i < ARRAY_SIZE(da8xx_mstpri_board_confs); i++) { + board_prio = &da8xx_mstpri_board_confs[i]; + + if (of_machine_is_compatible(board_prio->board)) + return board_prio; + } + + return NULL; +} + +static int da8xx_mstpri_probe(struct platform_device *pdev) +{ + const struct da8xx_mstpri_board_priorities *prio_list; + const struct da8xx_mstpri_descr *prio_descr; + const struct da8xx_mstpri_priority *prio; + struct device *dev = &pdev->dev; + struct regmap *mstpri; + int i, ret; + + mstpri = syscon_regmap_lookup_by_compatible("ti,da850-mstpri"); + if (IS_ERR(mstpri)) { + dev_err(dev, "unable to map mstpri registers\n"); + return PTR_ERR(mstpri); + } + + prio_list = da8xx_mstpri_get_board_prio(); + if (!prio_list) { + dev_err(dev, "no master priotities defined for board '%s'\n", + of_flat_dt_get_machine_name()); + return -EINVAL; + } + + for (i = 0; i < prio_list->numprio; i++) { + prio = &prio_list->priorities[i]; + prio_descr = &da8xx_mstpri_priority_list[prio->which]; + + ret = regmap_update_bits(mstpri, prio_descr->reg, + prio_descr->mask, + prio->val << prio_descr->shift); + if (ret) { + dev_warn(dev, + "error updating bits for register [%d]: %d\n", + prio_descr->reg, ret); + continue; + } + } + + return 0; +} + +static const struct of_device_id da8xx_mstpri_of_match[] = { + { .compatible = "ti,da850-mstpri", }, + { }, +}; + +static struct platform_driver da8xx_mstpri_driver = { + .probe = da8xx_mstpri_probe, + .driver = { + .name = "da8xx-mstpri", + .of_match_table = da8xx_mstpri_of_match, + }, +}; +module_platform_driver(da8xx_mstpri_driver); + +MODULE_AUTHOR("Bartosz Golaszewski bgolaszewski@baylibre.com"); +MODULE_DESCRIPTION("TI da8xx master peripheral priority driver"); +MODULE_LICENSE("GPL v2");