diff options
Diffstat (limited to 'drivers/memory')
| -rw-r--r-- | drivers/memory/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/memory/Makefile | 1 | ||||
| -rw-r--r-- | drivers/memory/ti-aemif.c | 427 |
3 files changed, 439 insertions, 0 deletions
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig index a3640fe9852f..c59e9c96e86d 100644 --- a/drivers/memory/Kconfig +++ b/drivers/memory/Kconfig @@ -7,6 +7,17 @@ menuconfig MEMORY if MEMORY +config TI_AEMIF + tristate "Texas Instruments AEMIF driver" + depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF + help + This driver is for the AEMIF module available in Texas Instruments + SoCs. AEMIF stands for Asynchronous External Memory Interface and + is intended to provide a glue-less interface to a variety of + asynchronuous memory devices like ASRAM, NOR and NAND memory. A total + of 256M bytes of any of these memories can be accessed at a given + time via four chip selects with 64M byte access per chip select. + config TI_EMIF tristate "Texas Instruments EMIF driver" depends on ARCH_OMAP2PLUS diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile index f2bf25c801d0..71160a2b7313 100644 --- a/drivers/memory/Makefile +++ b/drivers/memory/Makefile @@ -5,6 +5,7 @@ ifeq ($(CONFIG_DDR),y) obj-$(CONFIG_OF) += of_memory.o endif +obj-$(CONFIG_TI_AEMIF) += ti-aemif.o obj-$(CONFIG_TI_EMIF) += emif.o obj-$(CONFIG_FSL_IFC) += fsl_ifc.o obj-$(CONFIG_MVEBU_DEVBUS) += mvebu-devbus.o diff --git a/drivers/memory/ti-aemif.c b/drivers/memory/ti-aemif.c new file mode 100644 index 000000000000..d3df7602f406 --- /dev/null +++ b/drivers/memory/ti-aemif.c @@ -0,0 +1,427 @@ +/* + * TI AEMIF driver + * + * Copyright (C) 2010 - 2013 Texas Instruments Incorporated. http://www.ti.com/ + * + * Authors: + * Murali Karicheri <m-karicheri2@ti.com> + * Ivan Khoronzhuk <ivan.khoronzhuk@ti.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/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +#define TA_SHIFT 2 +#define RHOLD_SHIFT 4 +#define RSTROBE_SHIFT 7 +#define RSETUP_SHIFT 13 +#define WHOLD_SHIFT 17 +#define WSTROBE_SHIFT 20 +#define WSETUP_SHIFT 26 +#define EW_SHIFT 30 +#define SS_SHIFT 31 + +#define TA(x) ((x) << TA_SHIFT) +#define RHOLD(x) ((x) << RHOLD_SHIFT) +#define RSTROBE(x) ((x) << RSTROBE_SHIFT) +#define RSETUP(x) ((x) << RSETUP_SHIFT) +#define WHOLD(x) ((x) << WHOLD_SHIFT) +#define WSTROBE(x) ((x) << WSTROBE_SHIFT) +#define WSETUP(x) ((x) << WSETUP_SHIFT) +#define EW(x) ((x) << EW_SHIFT) +#define SS(x) ((x) << SS_SHIFT) + +#define ASIZE_MAX 0x1 +#define TA_MAX 0x3 +#define RHOLD_MAX 0x7 +#define RSTROBE_MAX 0x3f +#define RSETUP_MAX 0xf +#define WHOLD_MAX 0x7 +#define WSTROBE_MAX 0x3f +#define WSETUP_MAX 0xf +#define EW_MAX 0x1 +#define SS_MAX 0x1 +#define NUM_CS 4 + +#define TA_VAL(x) (((x) & TA(TA_MAX)) >> TA_SHIFT) +#define RHOLD_VAL(x) (((x) & RHOLD(RHOLD_MAX)) >> RHOLD_SHIFT) +#define RSTROBE_VAL(x) (((x) & RSTROBE(RSTROBE_MAX)) >> RSTROBE_SHIFT) +#define RSETUP_VAL(x) (((x) & RSETUP(RSETUP_MAX)) >> RSETUP_SHIFT) +#define WHOLD_VAL(x) (((x) & WHOLD(WHOLD_MAX)) >> WHOLD_SHIFT) +#define WSTROBE_VAL(x) (((x) & WSTROBE(WSTROBE_MAX)) >> WSTROBE_SHIFT) +#define WSETUP_VAL(x) (((x) & WSETUP(WSETUP_MAX)) >> WSETUP_SHIFT) +#define EW_VAL(x) (((x) & EW(EW_MAX)) >> EW_SHIFT) +#define SS_VAL(x) (((x) & SS(SS_MAX)) >> SS_SHIFT) + +#define NRCSR_OFFSET 0x00 +#define AWCCR_OFFSET 0x04 +#define A1CR_OFFSET 0x10 + +#define ACR_ASIZE_MASK 0x3 +#define ACR_EW_MASK BIT(30) +#define ACR_SS_MASK BIT(31) +#define ASIZE_16BIT 1 + +#define CONFIG_MASK (TA(TA_MAX) | \ + RHOLD(RHOLD_MAX) | \ + RSTROBE(RSTROBE_MAX) | \ + RSETUP(RSETUP_MAX) | \ + WHOLD(WHOLD_MAX) | \ + WSTROBE(WSTROBE_MAX) | \ + WSETUP(WSETUP_MAX) | \ + EW(EW_MAX) | SS(SS_MAX) | \ + ASIZE_MAX) + +/** + * struct aemif_cs_data: structure to hold cs parameters + * @cs: chip-select number + * @wstrobe: write strobe width, ns + * @rstrobe: read strobe width, ns + * @wsetup: write setup width, ns + * @whold: write hold width, ns + * @rsetup: read setup width, ns + * @rhold: read hold width, ns + * @ta: minimum turn around time, ns + * @enable_ss: enable/disable select strobe mode + * @enable_ew: enable/disable extended wait mode + * @asize: width of the asynchronous device's data bus + */ +struct aemif_cs_data { + u8 cs; + u16 wstrobe; + u16 rstrobe; + u8 wsetup; + u8 whold; + u8 rsetup; + u8 rhold; + u8 ta; + u8 enable_ss; + u8 enable_ew; + u8 asize; +}; + +/** + * struct aemif_device: structure to hold device data + * @base: base address of AEMIF registers + * @clk: source clock + * @clk_rate: clock's rate in kHz + * @num_cs: number of assigned chip-selects + * @cs_offset: start number of cs nodes + * @cs_data: array of chip-select settings + */ +struct aemif_device { + void __iomem *base; + struct clk *clk; + unsigned long clk_rate; + u8 num_cs; + int cs_offset; + struct aemif_cs_data cs_data[NUM_CS]; +}; + +/** + * aemif_calc_rate - calculate timing data. + * @pdev: platform device to calculate for + * @wanted: The cycle time needed in nanoseconds. + * @clk: The input clock rate in kHz. + * @max: The maximum divider value that can be programmed. + * + * On success, returns the calculated timing value minus 1 for easy + * programming into AEMIF timing registers, else negative errno. + */ +static int aemif_calc_rate(struct platform_device *pdev, int wanted, + unsigned long clk, int max) +{ + int result; + + result = DIV_ROUND_UP((wanted * clk), NSEC_PER_MSEC) - 1; + + dev_dbg(&pdev->dev, "%s: result %d from %ld, %d\n", __func__, result, + clk, wanted); + + /* It is generally OK to have a more relaxed timing than requested... */ + if (result < 0) + result = 0; + + /* ... But configuring tighter timings is not an option. */ + else if (result > max) + result = -EINVAL; + + return result; +} + +/** + * aemif_config_abus - configure async bus parameters + * @pdev: platform device to configure for + * @csnum: aemif chip select number + * + * This function programs the given timing values (in real clock) into the + * AEMIF registers taking the AEMIF clock into account. + * + * This function does not use any locking while programming the AEMIF + * because it is expected that there is only one user of a given + * chip-select. + * + * Returns 0 on success, else negative errno. + */ +static int aemif_config_abus(struct platform_device *pdev, int csnum) +{ + struct aemif_device *aemif = platform_get_drvdata(pdev); + struct aemif_cs_data *data = &aemif->cs_data[csnum]; + int ta, rhold, rstrobe, rsetup, whold, wstrobe, wsetup; + unsigned long clk_rate = aemif->clk_rate; + unsigned offset; + u32 set, val; + + offset = A1CR_OFFSET + (data->cs - aemif->cs_offset) * 4; + + ta = aemif_calc_rate(pdev, data->ta, clk_rate, TA_MAX); + rhold = aemif_calc_rate(pdev, data->rhold, clk_rate, RHOLD_MAX); + rstrobe = aemif_calc_rate(pdev, data->rstrobe, clk_rate, RSTROBE_MAX); + rsetup = aemif_calc_rate(pdev, data->rsetup, clk_rate, RSETUP_MAX); + whold = aemif_calc_rate(pdev, data->whold, clk_rate, WHOLD_MAX); + wstrobe = aemif_calc_rate(pdev, data->wstrobe, clk_rate, WSTROBE_MAX); + wsetup = aemif_calc_rate(pdev, data->wsetup, clk_rate, WSETUP_MAX); + + if (ta < 0 || rhold < 0 || rstrobe < 0 || rsetup < 0 || + whold < 0 || wstrobe < 0 || wsetup < 0) { + dev_err(&pdev->dev, "%s: cannot get suitable timings\n", + __func__); + return -EINVAL; + } + + set = TA(ta) | RHOLD(rhold) | RSTROBE(rstrobe) | RSETUP(rsetup) | + WHOLD(whold) | WSTROBE(wstrobe) | WSETUP(wsetup); + + set |= (data->asize & ACR_ASIZE_MASK); + if (data->enable_ew) + set |= ACR_EW_MASK; + if (data->enable_ss) + set |= ACR_SS_MASK; + + val = readl(aemif->base + offset); + val &= ~CONFIG_MASK; + val |= set; + writel(val, aemif->base + offset); + + return 0; +} + +static inline int aemif_cycles_to_nsec(int val, unsigned long clk_rate) +{ + return ((val + 1) * NSEC_PER_MSEC) / clk_rate; +} + +/** + * aemif_get_hw_params - function to read hw register values + * @pdev: platform device to read for + * @csnum: aemif chip select number + * + * This function reads the defaults from the registers and update + * the timing values. Required for get/set commands and also for + * the case when driver needs to use defaults in hardware. + */ +static void aemif_get_hw_params(struct platform_device *pdev, int csnum) +{ + struct aemif_device *aemif = platform_get_drvdata(pdev); + struct aemif_cs_data *data = &aemif->cs_data[csnum]; + unsigned long clk_rate = aemif->clk_rate; + u32 val, offset; + + offset = A1CR_OFFSET + (data->cs - aemif->cs_offset) * 4; + val = readl(aemif->base + offset); + + data->ta = aemif_cycles_to_nsec(TA_VAL(val), clk_rate); + data->rhold = aemif_cycles_to_nsec(RHOLD_VAL(val), clk_rate); + data->rstrobe = aemif_cycles_to_nsec(RSTROBE_VAL(val), clk_rate); + data->rsetup = aemif_cycles_to_nsec(RSETUP_VAL(val), clk_rate); + data->whold = aemif_cycles_to_nsec(WHOLD_VAL(val), clk_rate); + data->wstrobe = aemif_cycles_to_nsec(WSTROBE_VAL(val), clk_rate); + data->wsetup = aemif_cycles_to_nsec(WSETUP_VAL(val), clk_rate); + data->enable_ew = EW_VAL(val); + data->enable_ss = SS_VAL(val); + data->asize = val & ASIZE_MAX; +} + +/** + * of_aemif_parse_abus_config - parse CS configuration from DT + * @pdev: platform device to parse for + * @np: device node ptr + * + * This function update the emif async bus configuration based on the values + * configured in a cs device binding node. + */ +static int of_aemif_parse_abus_config(struct platform_device *pdev, + struct device_node *np) +{ + struct aemif_device *aemif = platform_get_drvdata(pdev); + struct aemif_cs_data *data; + u32 cs; + u32 val; + + if (of_property_read_u32(np, "ti,cs-chipselect", &cs)) { + dev_dbg(&pdev->dev, "cs property is required"); + return -EINVAL; + } + + if (cs - aemif->cs_offset >= NUM_CS || cs < aemif->cs_offset) { + dev_dbg(&pdev->dev, "cs number is incorrect %d", cs); + return -EINVAL; + } + + if (aemif->num_cs >= NUM_CS) { + dev_dbg(&pdev->dev, "cs count is more than %d", NUM_CS); + return -EINVAL; + } + + data = &aemif->cs_data[aemif->num_cs]; + data->cs = cs; + + /* read the current value in the hw register */ + aemif_get_hw_params(pdev, aemif->num_cs++); + + /* override the values from device node */ + if (!of_property_read_u32(np, "ti,cs-min-turnaround-ns", &val)) + data->ta = val; + + if (!of_property_read_u32(np, "ti,cs-read-hold-ns", &val)) + data->rhold = val; + + if (!of_property_read_u32(np, "ti,cs-read-strobe-ns", &val)) + data->rstrobe = val; + + if (!of_property_read_u32(np, "ti,cs-read-setup-ns", &val)) + data->rsetup = val; + + if (!of_property_read_u32(np, "ti,cs-write-hold-ns", &val)) + data->whold = val; + + if (!of_property_read_u32(np, "ti,cs-write-strobe-ns", &val)) + data->wstrobe = val; + + if (!of_property_read_u32(np, "ti,cs-write-setup-ns", &val)) + data->wsetup = val; + + if (!of_property_read_u32(np, "ti,cs-bus-width", &val)) + if (val == 16) + data->asize = 1; + data->enable_ew = of_property_read_bool(np, "ti,cs-extended-wait-mode"); + data->enable_ss = of_property_read_bool(np, "ti,cs-select-strobe-mode"); + return 0; +} + +static const struct of_device_id aemif_of_match[] = { + { .compatible = "ti,davinci-aemif", }, + { .compatible = "ti,da850-aemif", }, + {}, +}; + +static int aemif_probe(struct platform_device *pdev) +{ + int i; + int ret = -ENODEV; + struct resource *res; + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *child_np; + struct aemif_device *aemif; + + if (np == NULL) + return 0; + + aemif = devm_kzalloc(dev, sizeof(*aemif), GFP_KERNEL); + if (!aemif) + return -ENOMEM; + + platform_set_drvdata(pdev, aemif); + + aemif->clk = devm_clk_get(dev, NULL); + if (IS_ERR(aemif->clk)) { + dev_err(dev, "cannot get clock 'aemif'\n"); + return PTR_ERR(aemif->clk); + } + + clk_prepare_enable(aemif->clk); + aemif->clk_rate = clk_get_rate(aemif->clk) / MSEC_PER_SEC; + + if (of_device_is_compatible(np, "ti,da850-aemif")) + aemif->cs_offset = 2; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + aemif->base = devm_ioremap_resource(dev, res); + if (IS_ERR(aemif->base)) { + ret = PTR_ERR(aemif->base); + goto error; + } + + /* + * For every controller device node, there is a cs device node that + * describe the bus configuration parameters. This functions iterate + * over these nodes and update the cs data array. + */ + for_each_available_child_of_node(np, child_np) { + ret = of_aemif_parse_abus_config(pdev, child_np); + if (ret < 0) + goto error; + } + + for (i = 0; i < aemif->num_cs; i++) { + ret = aemif_config_abus(pdev, i); + if (ret < 0) { + dev_err(dev, "Error configuring chip select %d\n", + aemif->cs_data[i].cs); + goto error; + } + } + + /* + * Create a child devices explicitly from here to + * guarantee that the child will be probed after the AEMIF timing + * parameters are set. + */ + for_each_available_child_of_node(np, child_np) { + ret = of_platform_populate(child_np, NULL, NULL, dev); + if (ret < 0) + goto error; + } + + return 0; +error: + clk_disable_unprepare(aemif->clk); + return ret; +} + +static int aemif_remove(struct platform_device *pdev) +{ + struct aemif_device *aemif = platform_get_drvdata(pdev); + + clk_disable_unprepare(aemif->clk); + return 0; +} + +static struct platform_driver aemif_driver = { + .probe = aemif_probe, + .remove = aemif_remove, + .driver = { + .name = KBUILD_MODNAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(aemif_of_match), + }, +}; + +module_platform_driver(aemif_driver); + +MODULE_AUTHOR("Murali Karicheri <m-karicheri2@ti.com>"); +MODULE_AUTHOR("Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>"); +MODULE_DESCRIPTION("Texas Instruments AEMIF driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" KBUILD_MODNAME); |