diff options
| -rw-r--r-- | drivers/char/hw_random/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/char/hw_random/omap-rng.c | 352 |
2 files changed, 305 insertions, 53 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 2f9dbf7..5d7be1d 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -153,12 +153,12 @@ config HW_RANDOM_IXP4XX config HW_RANDOM_OMAP tristate "OMAP Random Number Generator support" - depends on HW_RANDOM && (ARCH_OMAP16XX || ARCH_OMAP2) + depends on HW_RANDOM && (ARCH_OMAP16XX || ARCH_OMAP2PLUS) default HW_RANDOM ---help--- This driver provides kernel-side support for the Random Number - Generator hardware found on OMAP16xx and OMAP24xx multimedia - processors. + Generator hardware found on OMAP16xx, OMAP2/3/4/5 and AM33xx/AM43xx + multimedia processors. To compile this driver as a module, choose M here: the module will be called omap-rng. diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c index 3076c9d..f3f7142 100644 --- a/drivers/char/hw_random/omap-rng.c +++ b/drivers/char/hw_random/omap-rng.c @@ -27,57 +27,138 @@ #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_address.h> +#include <linux/interrupt.h> #include <asm/io.h> -#define RNG_OUT_REG 0x00 /* Output register */ -#define RNG_STAT_REG 0x04 /* Status register - [0] = STAT_BUSY */ -#define RNG_ALARM_REG 0x24 /* Alarm register - [7:0] = ALARM_COUNTER */ -#define RNG_CONFIG_REG 0x28 /* Configuration register - [11:6] = RESET_COUNT - [5:3] = RING2_DELAY - [2:0] = RING1_DELAY */ -#define RNG_REV_REG 0x3c /* Revision register - [7:0] = REV_NB */ -#define RNG_MASK_REG 0x40 /* Mask and reset register - [2] = IT_EN - [1] = SOFTRESET - [0] = AUTOIDLE */ -#define RNG_SYSSTATUS 0x44 /* System status - [0] = RESETDONE */ +#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_private_data - RNG IP block-specific data - * @base: virtual address of the beginning of the RNG IP block registers - * @mem_res: struct resource * for the IP block registers physical memory + * 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_private_data { - void __iomem *base; - struct resource *mem_res; +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); }; -static inline u32 omap_rng_read_reg(struct omap_rng_private_data *priv, int reg) +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) { - return __raw_readl(priv->base + reg); + __raw_writel(val, priv->base + priv->pdata->regs[reg]); } -static inline void omap_rng_write_reg(struct omap_rng_private_data *priv, - int reg, u32 val) +static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv) { - __raw_writel(val, priv->base + reg); + return omap_rng_read(priv, RNG_STATUS_REG) ? 0 : 1; +} + +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 omap_rng_data_present(struct hwrng *rng, int wait) { - struct omap_rng_private_data *priv; + struct omap_rng_dev *priv; int data, i; - priv = (struct omap_rng_private_data *)rng->priv; + priv = (struct omap_rng_dev *)rng->priv; for (i = 0; i < 20; i++) { - data = omap_rng_read_reg(priv, RNG_STAT_REG) ? 0 : 1; + data = priv->pdata->data_present(priv); if (data || !wait) break; /* RNG produces data fast enough (2+ MBit/sec, even @@ -92,36 +173,202 @@ static int omap_rng_data_present(struct hwrng *rng, int wait) static int omap_rng_data_read(struct hwrng *rng, u32 *data) { - struct omap_rng_private_data *priv; + 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 omap4_rng_init(struct omap_rng_dev *priv) +{ + u32 val; + + /* Return if RNG is already running. */ + if (omap_rng_read(priv, RNG_CONFIG_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_CONFIG_REG, val); +} + +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 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 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; - priv = (struct omap_rng_private_data *)rng->priv; + omap_rng_write(priv, RNG_FRODETUNE_REG, fro_detune); + omap_rng_write(priv, RNG_FROENABLE_REG, fro_enable); - *data = omap_rng_read_reg(priv, RNG_OUT_REG); + omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_SHUTDOWN_OFLO_MASK); - return sizeof(u32); + return IRQ_HANDLED; } 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 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 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" }, + { + .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_private_data *priv; + struct omap_rng_dev *priv; + struct resource *res; + struct device *dev = &pdev->dev; int ret; - priv = devm_kzalloc(&pdev->dev, sizeof(struct omap_rng_private_data), - GFP_KERNEL); + priv = devm_kzalloc(dev, sizeof(struct omap_rng_dev), GFP_KERNEL); if (!priv) { dev_err(&pdev->dev, "could not allocate memory\n"); return -ENOMEM; @@ -129,9 +376,10 @@ static int omap_rng_probe(struct platform_device *pdev) omap_rng_ops.priv = (unsigned long)priv; platform_set_drvdata(pdev, priv); + priv->dev = dev; - priv->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - priv->base = devm_ioremap_resource(&pdev->dev, priv->mem_res); + 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; @@ -140,14 +388,17 @@ static int omap_rng_probe(struct platform_device *pdev) 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_reg(priv, RNG_REV_REG)); - - omap_rng_write_reg(priv, RNG_MASK_REG, 0x1); + omap_rng_read(priv, RNG_REV_REG)); return 0; @@ -155,16 +406,17 @@ err_register: priv->base = NULL; pm_runtime_disable(&pdev->dev); err_ioremap: + dev_err(dev, "initialization failed.\n"); return ret; } static int __exit omap_rng_remove(struct platform_device *pdev) { - struct omap_rng_private_data *priv = platform_get_drvdata(pdev); + struct omap_rng_dev *priv = platform_get_drvdata(pdev); hwrng_unregister(&omap_rng_ops); - omap_rng_write_reg(priv, RNG_MASK_REG, 0x0); + priv->pdata->cleanup(priv); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); @@ -176,9 +428,9 @@ static int __exit omap_rng_remove(struct platform_device *pdev) static int omap_rng_suspend(struct device *dev) { - struct omap_rng_private_data *priv = dev_get_drvdata(dev); + struct omap_rng_dev *priv = dev_get_drvdata(dev); - omap_rng_write_reg(priv, RNG_MASK_REG, 0x0); + priv->pdata->cleanup(priv); pm_runtime_put_sync(dev); return 0; @@ -186,10 +438,10 @@ static int omap_rng_suspend(struct device *dev) static int omap_rng_resume(struct device *dev) { - struct omap_rng_private_data *priv = dev_get_drvdata(dev); + struct omap_rng_dev *priv = dev_get_drvdata(dev); pm_runtime_get_sync(dev); - omap_rng_write_reg(priv, RNG_MASK_REG, 0x1); + priv->pdata->init(priv); return 0; } |