diff options
author | 2015-08-04 12:17:53 -0700 | |
---|---|---|
committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/char/hw_random/omap-rng.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/char/hw_random/omap-rng.c')
-rw-r--r-- | kernel/drivers/char/hw_random/omap-rng.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/kernel/drivers/char/hw_random/omap-rng.c b/kernel/drivers/char/hw_random/omap-rng.c new file mode 100644 index 000000000..8a1432e8b --- /dev/null +++ b/kernel/drivers/char/hw_random/omap-rng.c @@ -0,0 +1,460 @@ +/* + * omap-rng.c - RNG driver for TI OMAP CPU family + * + * Author: Deepak Saxena <dsaxena@plexity.net> + * + * Copyright 2005 (c) MontaVista Software, Inc. + * + * Mostly based on original driver: + * + * Copyright (C) 2005 Nokia Corporation + * Author: Juha Yrjölä <juha.yrjola@nokia.com> + * + * 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/module.h> +#include <linux/init.h> +#include <linux/random.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/hw_random.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/interrupt.h> + +#include <asm/io.h> + +#define RNG_REG_STATUS_RDY (1 << 0) + +#define RNG_REG_INTACK_RDY_MASK (1 << 0) +#define RNG_REG_INTACK_SHUTDOWN_OFLO_MASK (1 << 1) +#define RNG_SHUTDOWN_OFLO_MASK (1 << 1) + +#define RNG_CONTROL_STARTUP_CYCLES_SHIFT 16 +#define RNG_CONTROL_STARTUP_CYCLES_MASK (0xffff << 16) +#define RNG_CONTROL_ENABLE_TRNG_SHIFT 10 +#define RNG_CONTROL_ENABLE_TRNG_MASK (1 << 10) + +#define RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT 16 +#define RNG_CONFIG_MAX_REFIL_CYCLES_MASK (0xffff << 16) +#define RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT 0 +#define RNG_CONFIG_MIN_REFIL_CYCLES_MASK (0xff << 0) + +#define RNG_CONTROL_STARTUP_CYCLES 0xff +#define RNG_CONFIG_MIN_REFIL_CYCLES 0x21 +#define RNG_CONFIG_MAX_REFIL_CYCLES 0x22 + +#define RNG_ALARMCNT_ALARM_TH_SHIFT 0x0 +#define RNG_ALARMCNT_ALARM_TH_MASK (0xff << 0) +#define RNG_ALARMCNT_SHUTDOWN_TH_SHIFT 16 +#define RNG_ALARMCNT_SHUTDOWN_TH_MASK (0x1f << 16) +#define RNG_ALARM_THRESHOLD 0xff +#define RNG_SHUTDOWN_THRESHOLD 0x4 + +#define RNG_REG_FROENABLE_MASK 0xffffff +#define RNG_REG_FRODETUNE_MASK 0xffffff + +#define OMAP2_RNG_OUTPUT_SIZE 0x4 +#define OMAP4_RNG_OUTPUT_SIZE 0x8 + +enum { + RNG_OUTPUT_L_REG = 0, + RNG_OUTPUT_H_REG, + RNG_STATUS_REG, + RNG_INTMASK_REG, + RNG_INTACK_REG, + RNG_CONTROL_REG, + RNG_CONFIG_REG, + RNG_ALARMCNT_REG, + RNG_FROENABLE_REG, + RNG_FRODETUNE_REG, + RNG_ALARMMASK_REG, + RNG_ALARMSTOP_REG, + RNG_REV_REG, + RNG_SYSCONFIG_REG, +}; + +static const u16 reg_map_omap2[] = { + [RNG_OUTPUT_L_REG] = 0x0, + [RNG_STATUS_REG] = 0x4, + [RNG_CONFIG_REG] = 0x28, + [RNG_REV_REG] = 0x3c, + [RNG_SYSCONFIG_REG] = 0x40, +}; + +static const u16 reg_map_omap4[] = { + [RNG_OUTPUT_L_REG] = 0x0, + [RNG_OUTPUT_H_REG] = 0x4, + [RNG_STATUS_REG] = 0x8, + [RNG_INTMASK_REG] = 0xc, + [RNG_INTACK_REG] = 0x10, + [RNG_CONTROL_REG] = 0x14, + [RNG_CONFIG_REG] = 0x18, + [RNG_ALARMCNT_REG] = 0x1c, + [RNG_FROENABLE_REG] = 0x20, + [RNG_FRODETUNE_REG] = 0x24, + [RNG_ALARMMASK_REG] = 0x28, + [RNG_ALARMSTOP_REG] = 0x2c, + [RNG_REV_REG] = 0x1FE0, + [RNG_SYSCONFIG_REG] = 0x1FE4, +}; + +struct omap_rng_dev; +/** + * struct omap_rng_pdata - RNG IP block-specific data + * @regs: Pointer to the register offsets structure. + * @data_size: No. of bytes in RNG output. + * @data_present: Callback to determine if data is available. + * @init: Callback for IP specific initialization sequence. + * @cleanup: Callback for IP specific cleanup sequence. + */ +struct omap_rng_pdata { + u16 *regs; + u32 data_size; + u32 (*data_present)(struct omap_rng_dev *priv); + int (*init)(struct omap_rng_dev *priv); + void (*cleanup)(struct omap_rng_dev *priv); +}; + +struct omap_rng_dev { + void __iomem *base; + struct device *dev; + const struct omap_rng_pdata *pdata; +}; + +static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg) +{ + return __raw_readl(priv->base + priv->pdata->regs[reg]); +} + +static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg, + u32 val) +{ + __raw_writel(val, priv->base + priv->pdata->regs[reg]); +} + +static int omap_rng_data_present(struct hwrng *rng, int wait) +{ + struct omap_rng_dev *priv; + int data, i; + + priv = (struct omap_rng_dev *)rng->priv; + + for (i = 0; i < 20; i++) { + data = priv->pdata->data_present(priv); + if (data || !wait) + break; + /* RNG produces data fast enough (2+ MBit/sec, even + * during "rngtest" loads, that these delays don't + * seem to trigger. We *could* use the RNG IRQ, but + * that'd be higher overhead ... so why bother? + */ + udelay(10); + } + return data; +} + +static int omap_rng_data_read(struct hwrng *rng, u32 *data) +{ + struct omap_rng_dev *priv; + u32 data_size, i; + + priv = (struct omap_rng_dev *)rng->priv; + data_size = priv->pdata->data_size; + + for (i = 0; i < data_size / sizeof(u32); i++) + data[i] = omap_rng_read(priv, RNG_OUTPUT_L_REG + i); + + if (priv->pdata->regs[RNG_INTACK_REG]) + omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK); + return data_size; +} + +static int omap_rng_init(struct hwrng *rng) +{ + struct omap_rng_dev *priv; + + priv = (struct omap_rng_dev *)rng->priv; + return priv->pdata->init(priv); +} + +static void omap_rng_cleanup(struct hwrng *rng) +{ + struct omap_rng_dev *priv; + + priv = (struct omap_rng_dev *)rng->priv; + priv->pdata->cleanup(priv); +} + +static struct hwrng omap_rng_ops = { + .name = "omap", + .data_present = omap_rng_data_present, + .data_read = omap_rng_data_read, + .init = omap_rng_init, + .cleanup = omap_rng_cleanup, +}; + +static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv) +{ + return omap_rng_read(priv, RNG_STATUS_REG) ? 0 : 1; +} + +static int omap2_rng_init(struct omap_rng_dev *priv) +{ + omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x1); + return 0; +} + +static void omap2_rng_cleanup(struct omap_rng_dev *priv) +{ + omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x0); +} + +static struct omap_rng_pdata omap2_rng_pdata = { + .regs = (u16 *)reg_map_omap2, + .data_size = OMAP2_RNG_OUTPUT_SIZE, + .data_present = omap2_rng_data_present, + .init = omap2_rng_init, + .cleanup = omap2_rng_cleanup, +}; + +#if defined(CONFIG_OF) +static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv) +{ + return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY; +} + +static int omap4_rng_init(struct omap_rng_dev *priv) +{ + u32 val; + + /* Return if RNG is already running. */ + if (omap_rng_read(priv, RNG_CONTROL_REG) & RNG_CONTROL_ENABLE_TRNG_MASK) + return 0; + + val = RNG_CONFIG_MIN_REFIL_CYCLES << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT; + val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT; + omap_rng_write(priv, RNG_CONFIG_REG, val); + + omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0); + omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK); + val = RNG_ALARM_THRESHOLD << RNG_ALARMCNT_ALARM_TH_SHIFT; + val |= RNG_SHUTDOWN_THRESHOLD << RNG_ALARMCNT_SHUTDOWN_TH_SHIFT; + omap_rng_write(priv, RNG_ALARMCNT_REG, val); + + val = RNG_CONTROL_STARTUP_CYCLES << RNG_CONTROL_STARTUP_CYCLES_SHIFT; + val |= RNG_CONTROL_ENABLE_TRNG_MASK; + omap_rng_write(priv, RNG_CONTROL_REG, val); + + return 0; +} + +static void omap4_rng_cleanup(struct omap_rng_dev *priv) +{ + int val; + + val = omap_rng_read(priv, RNG_CONTROL_REG); + val &= ~RNG_CONTROL_ENABLE_TRNG_MASK; + omap_rng_write(priv, RNG_CONTROL_REG, val); +} + +static irqreturn_t omap4_rng_irq(int irq, void *dev_id) +{ + struct omap_rng_dev *priv = dev_id; + u32 fro_detune, fro_enable; + + /* + * Interrupt raised by a fro shutdown threshold, do the following: + * 1. Clear the alarm events. + * 2. De tune the FROs which are shutdown. + * 3. Re enable the shutdown FROs. + */ + omap_rng_write(priv, RNG_ALARMMASK_REG, 0x0); + omap_rng_write(priv, RNG_ALARMSTOP_REG, 0x0); + + fro_enable = omap_rng_read(priv, RNG_FROENABLE_REG); + fro_detune = ~fro_enable & RNG_REG_FRODETUNE_MASK; + fro_detune = fro_detune | omap_rng_read(priv, RNG_FRODETUNE_REG); + fro_enable = RNG_REG_FROENABLE_MASK; + + omap_rng_write(priv, RNG_FRODETUNE_REG, fro_detune); + omap_rng_write(priv, RNG_FROENABLE_REG, fro_enable); + + omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_SHUTDOWN_OFLO_MASK); + + return IRQ_HANDLED; +} + +static struct omap_rng_pdata omap4_rng_pdata = { + .regs = (u16 *)reg_map_omap4, + .data_size = OMAP4_RNG_OUTPUT_SIZE, + .data_present = omap4_rng_data_present, + .init = omap4_rng_init, + .cleanup = omap4_rng_cleanup, +}; + +static const struct of_device_id omap_rng_of_match[] = { + { + .compatible = "ti,omap2-rng", + .data = &omap2_rng_pdata, + }, + { + .compatible = "ti,omap4-rng", + .data = &omap4_rng_pdata, + }, + {}, +}; +MODULE_DEVICE_TABLE(of, omap_rng_of_match); + +static int of_get_omap_rng_device_details(struct omap_rng_dev *priv, + struct platform_device *pdev) +{ + const struct of_device_id *match; + struct device *dev = &pdev->dev; + int irq, err; + + match = of_match_device(of_match_ptr(omap_rng_of_match), dev); + if (!match) { + dev_err(dev, "no compatible OF match\n"); + return -EINVAL; + } + priv->pdata = match->data; + + if (of_device_is_compatible(dev->of_node, "ti,omap4-rng")) { + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "%s: error getting IRQ resource - %d\n", + __func__, irq); + return irq; + } + + err = devm_request_irq(dev, irq, omap4_rng_irq, + IRQF_TRIGGER_NONE, dev_name(dev), priv); + if (err) { + dev_err(dev, "unable to request irq %d, err = %d\n", + irq, err); + return err; + } + omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK); + } + return 0; +} +#else +static int of_get_omap_rng_device_details(struct omap_rng_dev *omap_rng, + struct platform_device *pdev) +{ + return -EINVAL; +} +#endif + +static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng) +{ + /* Only OMAP2/3 can be non-DT */ + omap_rng->pdata = &omap2_rng_pdata; + return 0; +} + +static int omap_rng_probe(struct platform_device *pdev) +{ + struct omap_rng_dev *priv; + struct resource *res; + struct device *dev = &pdev->dev; + int ret; + + priv = devm_kzalloc(dev, sizeof(struct omap_rng_dev), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + omap_rng_ops.priv = (unsigned long)priv; + platform_set_drvdata(pdev, priv); + priv->dev = dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(dev, res); + if (IS_ERR(priv->base)) { + ret = PTR_ERR(priv->base); + goto err_ioremap; + } + + pm_runtime_enable(&pdev->dev); + pm_runtime_get_sync(&pdev->dev); + + ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) : + get_omap_rng_device_details(priv); + if (ret) + goto err_ioremap; + + ret = hwrng_register(&omap_rng_ops); + if (ret) + goto err_register; + + dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n", + omap_rng_read(priv, RNG_REV_REG)); + + return 0; + +err_register: + priv->base = NULL; + pm_runtime_disable(&pdev->dev); +err_ioremap: + dev_err(dev, "initialization failed.\n"); + return ret; +} + +static int omap_rng_remove(struct platform_device *pdev) +{ + struct omap_rng_dev *priv = platform_get_drvdata(pdev); + + hwrng_unregister(&omap_rng_ops); + + priv->pdata->cleanup(priv); + + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static int __maybe_unused omap_rng_suspend(struct device *dev) +{ + struct omap_rng_dev *priv = dev_get_drvdata(dev); + + priv->pdata->cleanup(priv); + pm_runtime_put_sync(dev); + + return 0; +} + +static int __maybe_unused omap_rng_resume(struct device *dev) +{ + struct omap_rng_dev *priv = dev_get_drvdata(dev); + + pm_runtime_get_sync(dev); + priv->pdata->init(priv); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(omap_rng_pm, omap_rng_suspend, omap_rng_resume); + +static struct platform_driver omap_rng_driver = { + .driver = { + .name = "omap_rng", + .pm = &omap_rng_pm, + .of_match_table = of_match_ptr(omap_rng_of_match), + }, + .probe = omap_rng_probe, + .remove = omap_rng_remove, +}; + +module_platform_driver(omap_rng_driver); +MODULE_ALIAS("platform:omap_rng"); +MODULE_AUTHOR("Deepak Saxena (and others)"); +MODULE_LICENSE("GPL"); |