/* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and * only version 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/types.h> #include <linux/device.h> #include <linux/io.h> #include <linux/err.h> #include <linux/fs.h> #include <linux/miscdevice.h> #include <linux/uaccess.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/clk.h> #include <linux/seq_file.h> #include <linux/coresight.h> #include <linux/amba/bus.h> #include "coresight-priv.h" #define ETB_RAM_DEPTH_REG 0x004 #define ETB_STATUS_REG 0x00c #define ETB_RAM_READ_DATA_REG 0x010 #define ETB_RAM_READ_POINTER 0x014 #define ETB_RAM_WRITE_POINTER 0x018 #define ETB_TRG 0x01c #define ETB_CTL_REG 0x020 #define ETB_RWD_REG 0x024 #define ETB_FFSR 0x300 #define ETB_FFCR 0x304 #define ETB_ITMISCOP0 0xee0 #define ETB_ITTRFLINACK 0xee4 #define ETB_ITTRFLIN 0xee8 #define ETB_ITATBDATA0 0xeeC #define ETB_ITATBCTR2 0xef0 #define ETB_ITATBCTR1 0xef4 #define ETB_ITATBCTR0 0xef8 /* register description */ /* STS - 0x00C */ #define ETB_STATUS_RAM_FULL BIT(0) /* CTL - 0x020 */ #define ETB_CTL_CAPT_EN BIT(0) /* FFCR - 0x304 */ #define ETB_FFCR_EN_FTC BIT(0) #define ETB_FFCR_FON_MAN BIT(6) #define ETB_FFCR_STOP_FI BIT(12) #define ETB_FFCR_STOP_TRIGGER BIT(13) #define ETB_FFCR_BIT 6 #define ETB_FFSR_BIT 1 #define ETB_FRAME_SIZE_WORDS 4 /** * struct etb_drvdata - specifics associated to an ETB component * @base: memory mapped base address for this component. * @dev: the device entity associated to this component. * @csdev: component vitals needed by the framework. * @miscdev: specifics to handle "/dev/xyz.etb" entry. * @clk: the clock this component is associated to. * @spinlock: only one at a time pls. * @in_use: synchronise user space access to etb buffer. * @buf: area of memory where ETB buffer content gets sent. * @buffer_depth: size of @buf. * @enable: this ETB is being used. * @trigger_cntr: amount of words to store after a trigger. */ struct etb_drvdata { void __iomem *base; struct device *dev; struct coresight_device *csdev; struct miscdevice miscdev; struct clk *clk; spinlock_t spinlock; atomic_t in_use; u8 *buf; u32 buffer_depth; bool enable; u32 trigger_cntr; }; static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata) { int ret; u32 depth = 0; ret = clk_prepare_enable(drvdata->clk); if (ret) return ret; /* RO registers don't need locking */ depth = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG); clk_disable_unprepare(drvdata->clk); return depth; } static void etb_enable_hw(struct etb_drvdata *drvdata) { int i; u32 depth; CS_UNLOCK(drvdata->base); depth = drvdata->buffer_depth; /* reset write RAM pointer address */ writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); /* clear entire RAM buffer */ for (i = 0; i < depth; i++) writel_relaxed(0x0, drvdata->base + ETB_RWD_REG); /* reset write RAM pointer address */ writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); /* reset read RAM pointer address */ writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER); writel_relaxed(drvdata->trigger_cntr, drvdata->base + ETB_TRG); writel_relaxed(ETB_FFCR_EN_FTC | ETB_FFCR_STOP_TRIGGER, drvdata->base + ETB_FFCR); /* ETB trace capture enable */ writel_relaxed(ETB_CTL_CAPT_EN, drvdata->base + ETB_CTL_REG); CS_LOCK(drvdata->base); } static int etb_enable(struct coresight_device *csdev) { struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); int ret; unsigned long flags; ret = clk_prepare_enable(drvdata->clk); if (ret) return ret; spin_lock_irqsave(&drvdata->spinlock, flags); etb_enable_hw(drvdata); drvdata->enable = true; spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "ETB enabled\n"); return 0; } static void etb_disable_hw(struct etb_drvdata *drvdata) { u32 ffcr; CS_UNLOCK(drvdata->base); ffcr = readl_relaxed(drvdata->base + ETB_FFCR); /* stop formatter when a stop has completed */ ffcr |= ETB_FFCR_STOP_FI; writel_relaxed(ffcr, drvdata->base + ETB_FFCR); /* manually generate a flush of the system */ ffcr |= ETB_FFCR_FON_MAN; writel_relaxed(ffcr, drvdata->base + ETB_FFCR); if (coresight_timeout(drvdata->base, ETB_FFCR, ETB_FFCR_BIT, 0)) { dev_err(drvdata->dev, "timeout observed when probing at offset %#x\n", ETB_FFCR); } /* disable trace capture */ writel_relaxed(0x0, drvdata->base + ETB_CTL_REG); if (coresight_timeout(drvdata->base, ETB_FFSR, ETB_FFSR_BIT, 1)) { dev_err(drvdata->dev, "timeout observed when probing at offset %#x\n", ETB_FFCR); } CS_LOCK(drvdata->base); } static void etb_dump_hw(struct etb_drvdata *drvdata) { int i; u8 *buf_ptr; u32 read_data, depth; u32 read_ptr, write_ptr; u32 frame_off, frame_endoff; CS_UNLOCK(drvdata->base); read_ptr = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER); write_ptr = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER); frame_off = write_ptr % ETB_FRAME_SIZE_WORDS; frame_endoff = ETB_FRAME_SIZE_WORDS - frame_off; if (frame_off) { dev_err(drvdata->dev, "write_ptr: %lu not aligned to formatter frame size\n", (unsigned long)write_ptr); dev_err(drvdata->dev, "frameoff: %lu, frame_endoff: %lu\n", (unsigned long)frame_off, (unsigned long)frame_endoff); write_ptr += frame_endoff; } if ((readl_relaxed(drvdata->base + ETB_STATUS_REG) & ETB_STATUS_RAM_FULL) == 0) writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER); else writel_relaxed(write_ptr, drvdata->base + ETB_RAM_READ_POINTER); depth = drvdata->buffer_depth; buf_ptr = drvdata->buf; for (i = 0; i < depth; i++) { read_data = readl_relaxed(drvdata->base + ETB_RAM_READ_DATA_REG); *buf_ptr++ = read_data >> 0; *buf_ptr++ = read_data >> 8; *buf_ptr++ = read_data >> 16; *buf_ptr++ = read_data >> 24; } if (frame_off) { buf_ptr -= (frame_endoff * 4); for (i = 0; i < frame_endoff; i++) { *buf_ptr++ = 0x0; *buf_ptr++ = 0x0; *buf_ptr++ = 0x0; *buf_ptr++ = 0x0; } } writel_relaxed(read_ptr, drvdata->base + ETB_RAM_READ_POINTER); CS_LOCK(drvdata->base); } static void etb_disable(struct coresight_device *csdev) { struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); unsigned long flags; spin_lock_irqsave(&drvdata->spinlock, flags); etb_disable_hw(drvdata); etb_dump_hw(drvdata); drvdata->enable = false; spin_unlock_irqrestore(&drvdata->spinlock, flags); clk_disable_unprepare(drvdata->clk); dev_info(drvdata->dev, "ETB disabled\n"); } static const struct coresight_ops_sink etb_sink_ops = { .enable = etb_enable, .disable = etb_disable, }; static const struct coresight_ops etb_cs_ops = { .sink_ops = &etb_sink_ops, }; static void etb_dump(struct etb_drvdata *drvdata) { unsigned long flags; spin_lock_irqsave(&drvdata->spinlock, flags); if (drvdata->enable) { etb_disable_hw(drvdata); etb_dump_hw(drvdata); etb_enable_hw(drvdata); } spin_unlock_irqrestore(&drvdata->spinlock, flags); dev_info(drvdata->dev, "ETB dumped\n"); } static int etb_open(struct inode *inode, struct file *file) { struct etb_drvdata *drvdata = container_of(file->private_data, struct etb_drvdata, miscdev); if (atomic_cmpxchg(&drvdata->in_use, 0, 1)) return -EBUSY; dev_dbg(drvdata->dev, "%s: successfully opened\n", __func__); return 0; } static ssize_t etb_read(struct file *file, char __user *data, size_t len, loff_t *ppos) { u32 depth; struct etb_drvdata *drvdata = container_of(file->private_data, struct etb_drvdata, miscdev); etb_dump(drvdata); depth = drvdata->buffer_depth; if (*ppos + len > depth * 4) len = depth * 4 - *ppos; if (copy_to_user(data, drvdata->buf + *ppos, len)) { dev_dbg(drvdata->dev, "%s: copy_to_user failed\n", __func__); return -EFAULT; } *ppos += len; dev_dbg(drvdata->dev, "%s: %d bytes copied, %d bytes left\n", __func__, len, (int) (depth * 4 - *ppos)); return len; } static int etb_release(struct inode *inode, struct file *file) { struct etb_drvdata *drvdata = container_of(file->private_data, struct etb_drvdata, miscdev); atomic_set(&drvdata->in_use, 0); dev_dbg(drvdata->dev, "%s: released\n", __func__); return 0; } static const struct file_operations etb_fops = { .owner = THIS_MODULE, .open = etb_open, .read = etb_read, .release = etb_release, .llseek = no_llseek, }; static ssize_t status_show(struct device *dev, struct device_attribute *attr, char *buf) { int ret; unsigned long flags; u32 etb_rdr, etb_sr, etb_rrp, etb_rwp; u32 etb_trg, etb_cr, etb_ffsr, etb_ffcr; struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); ret = clk_prepare_enable(drvdata->clk); if (ret) goto out; spin_lock_irqsave(&drvdata->spinlock, flags); CS_UNLOCK(drvdata->base); etb_rdr = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG); etb_sr = readl_relaxed(drvdata->base + ETB_STATUS_REG); etb_rrp = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER); etb_rwp = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER); etb_trg = readl_relaxed(drvdata->base + ETB_TRG); etb_cr = readl_relaxed(drvdata->base + ETB_CTL_REG); etb_ffsr = readl_relaxed(drvdata->base + ETB_FFSR); etb_ffcr = readl_relaxed(drvdata->base + ETB_FFCR); CS_LOCK(drvdata->base); spin_unlock_irqrestore(&drvdata->spinlock, flags); clk_disable_unprepare(drvdata->clk); return sprintf(buf, "Depth:\t\t0x%x\n" "Status:\t\t0x%x\n" "RAM read ptr:\t0x%x\n" "RAM wrt ptr:\t0x%x\n" "Trigger cnt:\t0x%x\n" "Control:\t0x%x\n" "Flush status:\t0x%x\n" "Flush ctrl:\t0x%x\n", etb_rdr, etb_sr, etb_rrp, etb_rwp, etb_trg, etb_cr, etb_ffsr, etb_ffcr); out: return -EINVAL; } static DEVICE_ATTR_RO(status); static ssize_t trigger_cntr_show(struct device *dev, struct device_attribute *attr, char *buf) { struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); unsigned long val = drvdata->trigger_cntr; return sprintf(buf, "%#lx\n", val); } static ssize_t trigger_cntr_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { int ret; unsigned long val; struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); ret = kstrtoul(buf, 16, &val); if (ret) return ret; drvdata->trigger_cntr = val; return size; } static DEVICE_ATTR_RW(trigger_cntr); static struct attribute *coresight_etb_attrs[] = { &dev_attr_trigger_cntr.attr, &dev_attr_status.attr, NULL, }; ATTRIBUTE_GROUPS(coresight_etb); static int etb_probe(struct amba_device *adev, const struct amba_id *id) { int ret; void __iomem *base; struct device *dev = &adev->dev; struct coresight_platform_data *pdata = NULL; struct etb_drvdata *drvdata; struct resource *res = &adev->res; struct coresight_desc *desc; struct device_node *np = adev->dev.of_node; if (np) { pdata = of_get_coresight_platform_data(dev, np); if (IS_ERR(pdata)) return PTR_ERR(pdata); adev->dev.platform_data = pdata; } drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); if (!drvdata) return -ENOMEM; drvdata->dev = &adev->dev; dev_set_drvdata(dev, drvdata); /* validity for the resource is already checked by the AMBA core */ base = devm_ioremap_resource(dev, res); if (IS_ERR(base)) return PTR_ERR(base); drvdata->base = base; spin_lock_init(&drvdata->spinlock); drvdata->clk = adev->pclk; ret = clk_prepare_enable(drvdata->clk); if (ret) return ret; drvdata->buffer_depth = etb_get_buffer_depth(drvdata); clk_disable_unprepare(drvdata->clk); if (drvdata->buffer_depth < 0) return -EINVAL; drvdata->buf = devm_kzalloc(dev, drvdata->buffer_depth * 4, GFP_KERNEL); if (!drvdata->buf) return -ENOMEM; desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL); if (!desc) return -ENOMEM; desc->type = CORESIGHT_DEV_TYPE_SINK; desc->subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER; desc->ops = &etb_cs_ops; desc->pdata = pdata; desc->dev = dev; desc->groups = coresight_etb_groups; drvdata->csdev = coresight_register(desc); if (IS_ERR(drvdata->csdev)) return PTR_ERR(drvdata->csdev); drvdata->miscdev.name = pdata->name; drvdata->miscdev.minor = MISC_DYNAMIC_MINOR; drvdata->miscdev.fops = &etb_fops; ret = misc_register(&drvdata->miscdev); if (ret) goto err_misc_register; dev_info(dev, "ETB initialized\n"); return 0; err_misc_register: coresight_unregister(drvdata->csdev); return ret; } static int etb_remove(struct amba_device *adev) { struct etb_drvdata *drvdata = amba_get_drvdata(adev); misc_deregister(&drvdata->miscdev); coresight_unregister(drvdata->csdev); return 0; } static struct amba_id etb_ids[] = { { .id = 0x0003b907, .mask = 0x0003ffff, }, { 0, 0}, }; static struct amba_driver etb_driver = { .drv = { .name = "coresight-etb10", .owner = THIS_MODULE, }, .probe = etb_probe, .remove = etb_remove, .id_table = etb_ids, }; module_amba_driver(etb_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("CoreSight Embedded Trace Buffer driver");