diff options
author | Ira Snyder <iws@ovro.caltech.edu> | 2011-02-11 13:34:30 +0000 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2011-05-19 16:55:10 +1000 |
commit | 0e1d715b5b982ee0099f3fbf6ad47dc8bda518a6 (patch) | |
tree | ea9171509fbf48558cec0598cedd6fb27d58d48e | |
parent | c186f0e177275e83728d7acfdf4a1b68793a7038 (diff) |
misc: Add CARMA DATA-FPGA Programmer support
This adds support for programming the data processing FPGAs on the OVRO
CARMA board. These FPGAs have a special programming sequence that
requires that we program the Freescale DMA engine, which is only
available inside the kernel.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
-rw-r--r-- | drivers/misc/carma/Kconfig | 8 | ||||
-rw-r--r-- | drivers/misc/carma/Makefile | 1 | ||||
-rw-r--r-- | drivers/misc/carma/carma-fpga-program.c | 1141 |
3 files changed, 1150 insertions, 0 deletions
diff --git a/drivers/misc/carma/Kconfig b/drivers/misc/carma/Kconfig index 4be183f7e6f1..c90370ed712b 100644 --- a/drivers/misc/carma/Kconfig +++ b/drivers/misc/carma/Kconfig @@ -7,3 +7,11 @@ config CARMA_FPGA Say Y here to include support for communicating with the data processing FPGAs on the OVRO CARMA board. +config CARMA_FPGA_PROGRAM + tristate "CARMA DATA-FPGA Programmer" + depends on FSL_SOC && PPC_83xx && MEDIA_SUPPORT && HAS_DMA && FSL_DMA + select VIDEOBUF_DMA_SG + default n + help + Say Y here to include support for programming the data processing + FPGAs on the OVRO CARMA board. diff --git a/drivers/misc/carma/Makefile b/drivers/misc/carma/Makefile index 0b69fa787953..ff36ac2ce534 100644 --- a/drivers/misc/carma/Makefile +++ b/drivers/misc/carma/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_CARMA_FPGA) += carma-fpga.o +obj-$(CONFIG_CARMA_FPGA_PROGRAM) += carma-fpga-program.o diff --git a/drivers/misc/carma/carma-fpga-program.c b/drivers/misc/carma/carma-fpga-program.c new file mode 100644 index 000000000000..7ce6065dc20e --- /dev/null +++ b/drivers/misc/carma/carma-fpga-program.c @@ -0,0 +1,1141 @@ +/* + * CARMA Board DATA-FPGA Programmer + * + * Copyright (c) 2009-2011 Ira W. Snyder <iws@ovro.caltech.edu> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/dma-mapping.h> +#include <linux/of_platform.h> +#include <linux/completion.h> +#include <linux/miscdevice.h> +#include <linux/dmaengine.h> +#include <linux/interrupt.h> +#include <linux/highmem.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/leds.h> +#include <linux/slab.h> +#include <linux/kref.h> +#include <linux/fs.h> +#include <linux/io.h> + +#include <media/videobuf-dma-sg.h> + +/* MPC8349EMDS specific get_immrbase() */ +#include <sysdev/fsl_soc.h> + +static const char drv_name[] = "carma-fpga-program"; + +/* + * Firmware images are always this exact size + * + * 12849552 bytes for a CARMA Digitizer Board (EP2S90 FPGAs) + * 18662880 bytes for a CARMA Correlator Board (EP2S130 FPGAs) + */ +#define FW_SIZE_EP2S90 12849552 +#define FW_SIZE_EP2S130 18662880 + +struct fpga_dev { + struct miscdevice miscdev; + + /* Reference count */ + struct kref ref; + + /* Device Registers */ + struct device *dev; + void __iomem *regs; + void __iomem *immr; + + /* Freescale DMA Device */ + struct dma_chan *chan; + + /* Interrupts */ + int irq, status; + struct completion completion; + + /* FPGA Bitfile */ + struct mutex lock; + + struct videobuf_dmabuf vb; + bool vb_allocated; + + /* max size and written bytes */ + size_t fw_size; + size_t bytes; +}; + +/* + * FPGA Bitfile Helpers + */ + +/** + * fpga_drop_firmware_data() - drop the bitfile image from memory + * @priv: the driver's private data structure + * + * LOCKING: must hold priv->lock + */ +static void fpga_drop_firmware_data(struct fpga_dev *priv) +{ + videobuf_dma_free(&priv->vb); + priv->vb_allocated = false; + priv->bytes = 0; +} + +/* + * Private Data Reference Count + */ + +static void fpga_dev_remove(struct kref *ref) +{ + struct fpga_dev *priv = container_of(ref, struct fpga_dev, ref); + + /* free any firmware image that was not programmed */ + fpga_drop_firmware_data(priv); + + mutex_destroy(&priv->lock); + kfree(priv); +} + +/* + * LED Trigger (could be a seperate module) + */ + +/* + * NOTE: this whole thing does have the problem that whenever the led's are + * NOTE: first set to use the fpga trigger, they could be in the wrong state + */ + +DEFINE_LED_TRIGGER(ledtrig_fpga); + +static void ledtrig_fpga_programmed(bool enabled) +{ + if (enabled) + led_trigger_event(ledtrig_fpga, LED_FULL); + else + led_trigger_event(ledtrig_fpga, LED_OFF); +} + +/* + * FPGA Register Helpers + */ + +/* Register Definitions */ +#define FPGA_CONFIG_CONTROL 0x40 +#define FPGA_CONFIG_STATUS 0x44 +#define FPGA_CONFIG_FIFO_SIZE 0x48 +#define FPGA_CONFIG_FIFO_USED 0x4C +#define FPGA_CONFIG_TOTAL_BYTE_COUNT 0x50 +#define FPGA_CONFIG_CUR_BYTE_COUNT 0x54 + +#define FPGA_FIFO_ADDRESS 0x3000 + +static int fpga_fifo_size(void __iomem *regs) +{ + return ioread32be(regs + FPGA_CONFIG_FIFO_SIZE); +} + +#define CFG_STATUS_ERR_MASK 0xfffe + +static int fpga_config_error(void __iomem *regs) +{ + return ioread32be(regs + FPGA_CONFIG_STATUS) & CFG_STATUS_ERR_MASK; +} + +static int fpga_fifo_empty(void __iomem *regs) +{ + return ioread32be(regs + FPGA_CONFIG_FIFO_USED) == 0; +} + +static void fpga_fifo_write(void __iomem *regs, u32 val) +{ + iowrite32be(val, regs + FPGA_FIFO_ADDRESS); +} + +static void fpga_set_byte_count(void __iomem *regs, u32 count) +{ + iowrite32be(count, regs + FPGA_CONFIG_TOTAL_BYTE_COUNT); +} + +#define CFG_CTL_ENABLE (1 << 0) +#define CFG_CTL_RESET (1 << 1) +#define CFG_CTL_DMA (1 << 2) + +static void fpga_programmer_enable(struct fpga_dev *priv, bool dma) +{ + u32 val; + + val = (dma) ? (CFG_CTL_ENABLE | CFG_CTL_DMA) : CFG_CTL_ENABLE; + iowrite32be(val, priv->regs + FPGA_CONFIG_CONTROL); +} + +static void fpga_programmer_disable(struct fpga_dev *priv) +{ + iowrite32be(0x0, priv->regs + FPGA_CONFIG_CONTROL); +} + +static void fpga_dump_registers(struct fpga_dev *priv) +{ + u32 control, status, size, used, total, curr; + + /* good status: do nothing */ + if (priv->status == 0) + return; + + /* Dump all status registers */ + control = ioread32be(priv->regs + FPGA_CONFIG_CONTROL); + status = ioread32be(priv->regs + FPGA_CONFIG_STATUS); + size = ioread32be(priv->regs + FPGA_CONFIG_FIFO_SIZE); + used = ioread32be(priv->regs + FPGA_CONFIG_FIFO_USED); + total = ioread32be(priv->regs + FPGA_CONFIG_TOTAL_BYTE_COUNT); + curr = ioread32be(priv->regs + FPGA_CONFIG_CUR_BYTE_COUNT); + + dev_err(priv->dev, "Configuration failed, dumping status registers\n"); + dev_err(priv->dev, "Control: 0x%.8x\n", control); + dev_err(priv->dev, "Status: 0x%.8x\n", status); + dev_err(priv->dev, "FIFO Size: 0x%.8x\n", size); + dev_err(priv->dev, "FIFO Used: 0x%.8x\n", used); + dev_err(priv->dev, "FIFO Total: 0x%.8x\n", total); + dev_err(priv->dev, "FIFO Curr: 0x%.8x\n", curr); +} + +/* + * FPGA Power Supply Code + */ + +#define CTL_PWR_CONTROL 0x2006 +#define CTL_PWR_STATUS 0x200A +#define CTL_PWR_FAIL 0x200B + +#define PWR_CONTROL_ENABLE 0x01 + +#define PWR_STATUS_ERROR_MASK 0x10 +#define PWR_STATUS_GOOD 0x0f + +/* + * Determine if the FPGA power is good for all supplies + */ +static bool fpga_power_good(struct fpga_dev *priv) +{ + u8 val; + + val = ioread8(priv->regs + CTL_PWR_STATUS); + if (val & PWR_STATUS_ERROR_MASK) + return false; + + return val == PWR_STATUS_GOOD; +} + +/* + * Disable the FPGA power supplies + */ +static void fpga_disable_power_supplies(struct fpga_dev *priv) +{ + unsigned long start; + u8 val; + + iowrite8(0x0, priv->regs + CTL_PWR_CONTROL); + + /* + * Wait 500ms for the power rails to discharge + * + * Without this delay, the CTL-CPLD state machine can get into a + * state where it is waiting for the power-goods to assert, but they + * never do. This only happens when enabling and disabling the + * power sequencer very rapidly. + * + * The loop below will also wait for the power goods to de-assert, + * but testing has shown that they are always disabled by the time + * the sleep completes. However, omitting the sleep and only waiting + * for the power-goods to de-assert was not sufficient to ensure + * that the power sequencer would not wedge itself. + */ + msleep(500); + + start = jiffies; + while (time_before(jiffies, start + HZ)) { + val = ioread8(priv->regs + CTL_PWR_STATUS); + if (!(val & PWR_STATUS_GOOD)) + break; + + usleep_range(5000, 10000); + } + + val = ioread8(priv->regs + CTL_PWR_STATUS); + if (val & PWR_STATUS_GOOD) { + dev_err(priv->dev, "power disable failed: " + "power goods: status 0x%.2x\n", val); + } + + if (val & PWR_STATUS_ERROR_MASK) { + dev_err(priv->dev, "power disable failed: " + "alarm bit set: status 0x%.2x\n", val); + } +} + +/** + * fpga_enable_power_supplies() - enable the DATA-FPGA power supplies + * @priv: the driver's private data structure + * + * Enable the DATA-FPGA power supplies, waiting up to 1 second for + * them to enable successfully. + * + * Returns 0 on success, -ERRNO otherwise + */ +static int fpga_enable_power_supplies(struct fpga_dev *priv) +{ + unsigned long start = jiffies; + + if (fpga_power_good(priv)) { + dev_dbg(priv->dev, "power was already good\n"); + return 0; + } + + iowrite8(PWR_CONTROL_ENABLE, priv->regs + CTL_PWR_CONTROL); + while (time_before(jiffies, start + HZ)) { + if (fpga_power_good(priv)) + return 0; + + usleep_range(5000, 10000); + } + + return fpga_power_good(priv) ? 0 : -ETIMEDOUT; +} + +/* + * Determine if the FPGA power supplies are all enabled + */ +static bool fpga_power_enabled(struct fpga_dev *priv) +{ + u8 val; + + val = ioread8(priv->regs + CTL_PWR_CONTROL); + if (val & PWR_CONTROL_ENABLE) + return true; + + return false; +} + +/* + * Determine if the FPGA's are programmed and running correctly + */ +static bool fpga_running(struct fpga_dev *priv) +{ + if (!fpga_power_good(priv)) + return false; + + /* Check the config done bit */ + return ioread32be(priv->regs + FPGA_CONFIG_STATUS) & (1 << 18); +} + +/* + * FPGA Programming Code + */ + +/** + * fpga_program_block() - put a block of data into the programmer's FIFO + * @priv: the driver's private data structure + * @buf: the data to program + * @count: the length of data to program (must be a multiple of 4 bytes) + * + * Returns 0 on success, -ERRNO otherwise + */ +static int fpga_program_block(struct fpga_dev *priv, void *buf, size_t count) +{ + u32 *data = buf; + int size = fpga_fifo_size(priv->regs); + int i, len; + unsigned long timeout; + + /* enforce correct data length for the FIFO */ + BUG_ON(count % 4 != 0); + + while (count > 0) { + + /* Get the size of the block to write (maximum is FIFO_SIZE) */ + len = min_t(size_t, count, size); + timeout = jiffies + HZ / 4; + + /* Write the block */ + for (i = 0; i < len / 4; i++) + fpga_fifo_write(priv->regs, data[i]); + + /* Update the amounts left */ + count -= len; + data += len / 4; + + /* Wait for the fifo to empty */ + while (true) { + + if (fpga_fifo_empty(priv->regs)) { + break; + } else { + dev_dbg(priv->dev, "Fifo not empty\n"); + cpu_relax(); + } + + if (fpga_config_error(priv->regs)) { + dev_err(priv->dev, "Error detected\n"); + return -EIO; + } + + if (time_after(jiffies, timeout)) { + dev_err(priv->dev, "Fifo drain timeout\n"); + return -ETIMEDOUT; + } + + usleep_range(5000, 10000); + } + } + + return 0; +} + +/** + * fpga_program_cpu() - program the DATA-FPGA's using the CPU + * @priv: the driver's private data structure + * + * This is useful when the DMA programming method fails. It is possible to + * wedge the Freescale DMA controller such that the DMA programming method + * always fails. This method has always succeeded. + * + * Returns 0 on success, -ERRNO otherwise + */ +static noinline int fpga_program_cpu(struct fpga_dev *priv) +{ + int ret; + + /* Disable the programmer */ + fpga_programmer_disable(priv); + + /* Set the total byte count */ + fpga_set_byte_count(priv->regs, priv->bytes); + dev_dbg(priv->dev, "total byte count %u bytes\n", priv->bytes); + + /* Enable the controller for programming */ + fpga_programmer_enable(priv, false); + dev_dbg(priv->dev, "enabled the controller\n"); + + /* Write each chunk of the FPGA bitfile to FPGA programmer */ + ret = fpga_program_block(priv, priv->vb.vaddr, priv->bytes); + if (ret) + goto out_disable_controller; + + /* Wait for the interrupt handler to signal that programming finished */ + ret = wait_for_completion_timeout(&priv->completion, 2 * HZ); + if (!ret) { + dev_err(priv->dev, "Timed out waiting for completion\n"); + ret = -ETIMEDOUT; + goto out_disable_controller; + } + + /* Retrieve the status from the interrupt handler */ + ret = priv->status; + +out_disable_controller: + fpga_programmer_disable(priv); + return ret; +} + +#define FIFO_DMA_ADDRESS 0xf0003000 +#define FIFO_MAX_LEN 4096 + +/** + * fpga_program_dma() - program the DATA-FPGA's using the DMA engine + * @priv: the driver's private data structure + * + * Program the DATA-FPGA's using the Freescale DMA engine. This requires that + * the engine is programmed such that the hardware DMA request lines can + * control the entire DMA transaction. The system controller FPGA then + * completely offloads the programming from the CPU. + * + * Returns 0 on success, -ERRNO otherwise + */ +static noinline int fpga_program_dma(struct fpga_dev *priv) +{ + struct videobuf_dmabuf *vb = &priv->vb; + struct dma_chan *chan = priv->chan; + struct dma_async_tx_descriptor *tx; + size_t num_pages, len, avail = 0; + struct dma_slave_config config; + struct scatterlist *sg; + struct sg_table table; + dma_cookie_t cookie; + int ret, i; + + /* Disable the programmer */ + fpga_programmer_disable(priv); + + /* Allocate a scatterlist for the DMA destination */ + num_pages = DIV_ROUND_UP(priv->bytes, FIFO_MAX_LEN); + ret = sg_alloc_table(&table, num_pages, GFP_KERNEL); + if (ret) { + dev_err(priv->dev, "Unable to allocate dst scatterlist\n"); + ret = -ENOMEM; + goto out_return; + } + + /* + * This is an ugly hack + * + * We fill in a scatterlist as if it were mapped for DMA. This is + * necessary because there exists no better structure for this + * inside the kernel code. + * + * As an added bonus, we can use the DMAEngine API for all of this, + * rather than inventing another extremely similar API. + */ + avail = priv->bytes; + for_each_sg(table.sgl, sg, num_pages, i) { + len = min_t(size_t, avail, FIFO_MAX_LEN); + sg_dma_address(sg) = FIFO_DMA_ADDRESS; + sg_dma_len(sg) = len; + + avail -= len; + } + + /* Map the buffer for DMA */ + ret = videobuf_dma_map(priv->dev, &priv->vb); + if (ret) { + dev_err(priv->dev, "Unable to map buffer for DMA\n"); + goto out_free_table; + } + + /* + * Configure the DMA channel to transfer FIFO_SIZE / 2 bytes per + * transaction, and then put it under external control + */ + memset(&config, 0, sizeof(config)); + config.direction = DMA_TO_DEVICE; + config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + config.dst_maxburst = fpga_fifo_size(priv->regs) / 2 / 4; + ret = chan->device->device_control(chan, DMA_SLAVE_CONFIG, + (unsigned long)&config); + if (ret) { + dev_err(priv->dev, "DMA slave configuration failed\n"); + goto out_dma_unmap; + } + + ret = chan->device->device_control(chan, FSLDMA_EXTERNAL_START, 1); + if (ret) { + dev_err(priv->dev, "DMA external control setup failed\n"); + goto out_dma_unmap; + } + + /* setup and submit the DMA transaction */ + tx = chan->device->device_prep_dma_sg(chan, + table.sgl, num_pages, + vb->sglist, vb->sglen, 0); + if (!tx) { + dev_err(priv->dev, "Unable to prep DMA transaction\n"); + ret = -ENOMEM; + goto out_dma_unmap; + } + + cookie = tx->tx_submit(tx); + if (dma_submit_error(cookie)) { + dev_err(priv->dev, "Unable to submit DMA transaction\n"); + ret = -ENOMEM; + goto out_dma_unmap; + } + + dma_async_memcpy_issue_pending(chan); + + /* Set the total byte count */ + fpga_set_byte_count(priv->regs, priv->bytes); + dev_dbg(priv->dev, "total byte count %u bytes\n", priv->bytes); + + /* Enable the controller for DMA programming */ + fpga_programmer_enable(priv, true); + dev_dbg(priv->dev, "enabled the controller\n"); + + /* Wait for the interrupt handler to signal that programming finished */ + ret = wait_for_completion_timeout(&priv->completion, 2 * HZ); + if (!ret) { + dev_err(priv->dev, "Timed out waiting for completion\n"); + ret = -ETIMEDOUT; + goto out_disable_controller; + } + + /* Retrieve the status from the interrupt handler */ + ret = priv->status; + +out_disable_controller: + fpga_programmer_disable(priv); +out_dma_unmap: + videobuf_dma_unmap(priv->dev, vb); +out_free_table: + sg_free_table(&table); +out_return: + return ret; +} + +/* + * Interrupt Handling + */ + +static irqreturn_t fpga_irq(int irq, void *dev_id) +{ + struct fpga_dev *priv = dev_id; + + /* Save the status */ + priv->status = fpga_config_error(priv->regs) ? -EIO : 0; + dev_dbg(priv->dev, "INTERRUPT status %d\n", priv->status); + fpga_dump_registers(priv); + + /* Disabling the programmer clears the interrupt */ + fpga_programmer_disable(priv); + + /* Notify any waiters */ + complete(&priv->completion); + + return IRQ_HANDLED; +} + +/* + * SYSFS Helpers + */ + +/** + * fpga_do_stop() - deconfigure (reset) the DATA-FPGA's + * @priv: the driver's private data structure + * + * LOCKING: must hold priv->lock + */ +static int fpga_do_stop(struct fpga_dev *priv) +{ + u32 val; + + /* Set the led to unprogrammed */ + ledtrig_fpga_programmed(false); + + /* Pulse the config line to reset the FPGA's */ + val = CFG_CTL_ENABLE | CFG_CTL_RESET; + iowrite32be(val, priv->regs + FPGA_CONFIG_CONTROL); + iowrite32be(0x0, priv->regs + FPGA_CONFIG_CONTROL); + + return 0; +} + +static noinline int fpga_do_program(struct fpga_dev *priv) +{ + int ret; + + if (priv->bytes != priv->fw_size) { + dev_err(priv->dev, "Incorrect bitfile size: got %zu bytes, " + "should be %zu bytes\n", + priv->bytes, priv->fw_size); + return -EINVAL; + } + + if (!fpga_power_enabled(priv)) { + dev_err(priv->dev, "Power not enabled\n"); + return -EINVAL; + } + + if (!fpga_power_good(priv)) { + dev_err(priv->dev, "Power not good\n"); + return -EINVAL; + } + + /* Set the LED to unprogrammed */ + ledtrig_fpga_programmed(false); + + /* Try to program the FPGA's using DMA */ + ret = fpga_program_dma(priv); + + /* If DMA failed or doesn't exist, try with CPU */ + if (ret) { + dev_warn(priv->dev, "Falling back to CPU programming\n"); + ret = fpga_program_cpu(priv); + } + + if (ret) { + dev_err(priv->dev, "Unable to program FPGA's\n"); + return ret; + } + + /* Drop the firmware bitfile from memory */ + fpga_drop_firmware_data(priv); + + dev_dbg(priv->dev, "FPGA programming successful\n"); + ledtrig_fpga_programmed(true); + + return 0; +} + +/* + * File Operations + */ + +static int fpga_open(struct inode *inode, struct file *filp) +{ + /* + * The miscdevice layer puts our struct miscdevice into the + * filp->private_data field. We use this to find our private + * data and then overwrite it with our own private structure. + */ + struct fpga_dev *priv = container_of(filp->private_data, + struct fpga_dev, miscdev); + unsigned int nr_pages; + int ret; + + /* We only allow one process at a time */ + ret = mutex_lock_interruptible(&priv->lock); + if (ret) + return ret; + + filp->private_data = priv; + kref_get(&priv->ref); + + /* Truncation: drop any existing data */ + if (filp->f_flags & O_TRUNC) + priv->bytes = 0; + + /* Check if we have already allocated a buffer */ + if (priv->vb_allocated) + return 0; + + /* Allocate a buffer to hold enough data for the bitfile */ + nr_pages = DIV_ROUND_UP(priv->fw_size, PAGE_SIZE); + ret = videobuf_dma_init_kernel(&priv->vb, DMA_TO_DEVICE, nr_pages); + if (ret) { + dev_err(priv->dev, "unable to allocate data buffer\n"); + mutex_unlock(&priv->lock); + kref_put(&priv->ref, fpga_dev_remove); + return ret; + } + + priv->vb_allocated = true; + return 0; +} + +static int fpga_release(struct inode *inode, struct file *filp) +{ + struct fpga_dev *priv = filp->private_data; + + mutex_unlock(&priv->lock); + kref_put(&priv->ref, fpga_dev_remove); + return 0; +} + +static ssize_t fpga_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + struct fpga_dev *priv = filp->private_data; + + /* FPGA bitfiles have an exact size: disallow anything else */ + if (priv->bytes >= priv->fw_size) + return -ENOSPC; + + count = min_t(size_t, priv->fw_size - priv->bytes, count); + if (copy_from_user(priv->vb.vaddr + priv->bytes, buf, count)) + return -EFAULT; + + priv->bytes += count; + return count; +} + +static ssize_t fpga_read(struct file *filp, char __user *buf, size_t count, + loff_t *f_pos) +{ + struct fpga_dev *priv = filp->private_data; + + count = min_t(size_t, priv->bytes - *f_pos, count); + if (copy_to_user(buf, priv->vb.vaddr + *f_pos, count)) + return -EFAULT; + + *f_pos += count; + return count; +} + +static loff_t fpga_llseek(struct file *filp, loff_t offset, int origin) +{ + struct fpga_dev *priv = filp->private_data; + loff_t newpos; + + /* only read-only opens are allowed to seek */ + if ((filp->f_flags & O_ACCMODE) != O_RDONLY) + return -EINVAL; + + switch (origin) { + case SEEK_SET: /* seek relative to the beginning of the file */ + newpos = offset; + break; + case SEEK_CUR: /* seek relative to current position in the file */ + newpos = filp->f_pos + offset; + break; + case SEEK_END: /* seek relative to the end of the file */ + newpos = priv->fw_size - offset; + break; + default: + return -EINVAL; + } + + /* check for sanity */ + if (newpos > priv->fw_size) + return -EINVAL; + + filp->f_pos = newpos; + return newpos; +} + +static const struct file_operations fpga_fops = { + .open = fpga_open, + .release = fpga_release, + .write = fpga_write, + .read = fpga_read, + .llseek = fpga_llseek, +}; + +/* + * Device Attributes + */ + +static ssize_t pfail_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + u8 val; + + val = ioread8(priv->regs + CTL_PWR_FAIL); + return snprintf(buf, PAGE_SIZE, "0x%.2x\n", val); +} + +static ssize_t pgood_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + return snprintf(buf, PAGE_SIZE, "%d\n", fpga_power_good(priv)); +} + +static ssize_t penable_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + return snprintf(buf, PAGE_SIZE, "%d\n", fpga_power_enabled(priv)); +} + +static ssize_t penable_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + unsigned long val; + int ret; + + if (strict_strtoul(buf, 0, &val)) + return -EINVAL; + + if (val) { + ret = fpga_enable_power_supplies(priv); + if (ret) + return ret; + } else { + fpga_do_stop(priv); + fpga_disable_power_supplies(priv); + } + + return count; +} + +static ssize_t program_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + return snprintf(buf, PAGE_SIZE, "%d\n", fpga_running(priv)); +} + +static ssize_t program_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fpga_dev *priv = dev_get_drvdata(dev); + unsigned long val; + int ret; + + if (strict_strtoul(buf, 0, &val)) + return -EINVAL; + + /* We can't have an image writer and be programming simultaneously */ + if (mutex_lock_interruptible(&priv->lock)) + return -ERESTARTSYS; + + /* Program or Reset the FPGA's */ + ret = val ? fpga_do_program(priv) : fpga_do_stop(priv); + if (ret) + goto out_unlock; + + /* Success */ + ret = count; + +out_unlock: + mutex_unlock(&priv->lock); + return ret; +} + +static DEVICE_ATTR(power_fail, S_IRUGO, pfail_show, NULL); +static DEVICE_ATTR(power_good, S_IRUGO, pgood_show, NULL); +static DEVICE_ATTR(power_enable, S_IRUGO | S_IWUSR, + penable_show, penable_store); + +static DEVICE_ATTR(program, S_IRUGO | S_IWUSR, + program_show, program_store); + +static struct attribute *fpga_attributes[] = { + &dev_attr_power_fail.attr, + &dev_attr_power_good.attr, + &dev_attr_power_enable.attr, + &dev_attr_program.attr, + NULL, +}; + +static const struct attribute_group fpga_attr_group = { + .attrs = fpga_attributes, +}; + +/* + * OpenFirmware Device Subsystem + */ + +#define SYS_REG_VERSION 0x00 +#define SYS_REG_GEOGRAPHIC 0x10 + +static bool dma_filter(struct dma_chan *chan, void *data) +{ + /* + * DMA Channel #0 is the only acceptable device + * + * This probably won't survive an unload/load cycle of the Freescale + * DMAEngine driver, but that won't be a problem + */ + return chan->chan_id == 0 && chan->device->dev_id == 0; +} + +static int fpga_of_remove(struct platform_device *op) +{ + struct fpga_dev *priv = dev_get_drvdata(&op->dev); + struct device *this_device = priv->miscdev.this_device; + + sysfs_remove_group(&this_device->kobj, &fpga_attr_group); + misc_deregister(&priv->miscdev); + + free_irq(priv->irq, priv); + irq_dispose_mapping(priv->irq); + + /* make sure the power supplies are off */ + fpga_disable_power_supplies(priv); + + /* unmap registers */ + iounmap(priv->immr); + iounmap(priv->regs); + + dma_release_channel(priv->chan); + + /* drop our reference to the private data structure */ + kref_put(&priv->ref, fpga_dev_remove); + return 0; +} + +/* CTL-CPLD Version Register */ +#define CTL_CPLD_VERSION 0x2000 + +static int fpga_of_probe(struct platform_device *op, + const struct of_device_id *match) +{ + struct device_node *of_node = op->dev.of_node; + struct device *this_device; + struct fpga_dev *priv; + dma_cap_mask_t mask; + u32 ver; + int ret; + + /* Allocate private data */ + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) { + dev_err(&op->dev, "Unable to allocate private data\n"); + ret = -ENOMEM; + goto out_return; + } + + /* Setup the miscdevice */ + priv->miscdev.minor = MISC_DYNAMIC_MINOR; + priv->miscdev.name = drv_name; + priv->miscdev.fops = &fpga_fops; + + kref_init(&priv->ref); + + dev_set_drvdata(&op->dev, priv); + priv->dev = &op->dev; + mutex_init(&priv->lock); + init_completion(&priv->completion); + videobuf_dma_init(&priv->vb); + + dev_set_drvdata(priv->dev, priv); + dma_cap_zero(mask); + dma_cap_set(DMA_MEMCPY, mask); + dma_cap_set(DMA_INTERRUPT, mask); + dma_cap_set(DMA_SLAVE, mask); + dma_cap_set(DMA_SG, mask); + + /* Get control of DMA channel #0 */ + priv->chan = dma_request_channel(mask, dma_filter, NULL); + if (!priv->chan) { + dev_err(&op->dev, "Unable to acquire DMA channel #0\n"); + ret = -ENODEV; + goto out_free_priv; + } + + /* Remap the registers for use */ + priv->regs = of_iomap(of_node, 0); + if (!priv->regs) { + dev_err(&op->dev, "Unable to ioremap registers\n"); + ret = -ENOMEM; + goto out_dma_release_channel; + } + + /* Remap the IMMR for use */ + priv->immr = ioremap(get_immrbase(), 0x100000); + if (!priv->immr) { + dev_err(&op->dev, "Unable to ioremap IMMR\n"); + ret = -ENOMEM; + goto out_unmap_regs; + } + + /* + * Check that external DMA is configured + * + * U-Boot does this for us, but we should check it and bail out if + * there is a problem. Failing to have this register setup correctly + * will cause the DMA controller to transfer a single cacheline + * worth of data, then wedge itself. + */ + if ((ioread32be(priv->immr + 0x114) & 0xE00) != 0xE00) { + dev_err(&op->dev, "External DMA control not configured\n"); + ret = -ENODEV; + goto out_unmap_immr; + } + + /* + * Check the CTL-CPLD version + * + * This driver uses the CTL-CPLD DATA-FPGA power sequencer, and we + * don't want to run on any version of the CTL-CPLD that does not use + * a compatible register layout. + * + * v2: changed register layout, added power sequencer + * v3: added glitch filter on the i2c overcurrent/overtemp outputs + */ + ver = ioread8(priv->regs + CTL_CPLD_VERSION); + if (ver != 0x02 && ver != 0x03) { + dev_err(&op->dev, "CTL-CPLD is not version 0x02 or 0x03!\n"); + ret = -ENODEV; + goto out_unmap_immr; + } + + /* Set the exact size that the firmware image should be */ + ver = ioread32be(priv->regs + SYS_REG_VERSION); + priv->fw_size = (ver & (1 << 18)) ? FW_SIZE_EP2S130 : FW_SIZE_EP2S90; + + /* Find the correct IRQ number */ + priv->irq = irq_of_parse_and_map(of_node, 0); + if (priv->irq == NO_IRQ) { + dev_err(&op->dev, "Unable to find IRQ line\n"); + ret = -ENODEV; + goto out_unmap_immr; + } + + /* Request the IRQ */ + ret = request_irq(priv->irq, fpga_irq, IRQF_SHARED, drv_name, priv); + if (ret) { + dev_err(&op->dev, "Unable to request IRQ %d\n", priv->irq); + ret = -ENODEV; + goto out_irq_dispose_mapping; + } + + /* Reset and stop the FPGA's, just in case */ + fpga_do_stop(priv); + + /* Register the miscdevice */ + ret = misc_register(&priv->miscdev); + if (ret) { + dev_err(&op->dev, "Unable to register miscdevice\n"); + goto out_free_irq; + } + + /* Create the sysfs files */ + this_device = priv->miscdev.this_device; + dev_set_drvdata(this_device, priv); + ret = sysfs_create_group(&this_device->kobj, &fpga_attr_group); + if (ret) { + dev_err(&op->dev, "Unable to create sysfs files\n"); + goto out_misc_deregister; + } + + dev_info(priv->dev, "CARMA FPGA Programmer: %s rev%s with %s FPGAs\n", + (ver & (1 << 17)) ? "Correlator" : "Digitizer", + (ver & (1 << 16)) ? "B" : "A", + (ver & (1 << 18)) ? "EP2S130" : "EP2S90"); + + return 0; + +out_misc_deregister: + misc_deregister(&priv->miscdev); +out_free_irq: + free_irq(priv->irq, priv); +out_irq_dispose_mapping: + irq_dispose_mapping(priv->irq); +out_unmap_immr: + iounmap(priv->immr); +out_unmap_regs: + iounmap(priv->regs); +out_dma_release_channel: + dma_release_channel(priv->chan); +out_free_priv: + kref_put(&priv->ref, fpga_dev_remove); +out_return: + return ret; +} + +static struct of_device_id fpga_of_match[] = { + { .compatible = "carma,fpga-programmer", }, + {}, +}; + +static struct of_platform_driver fpga_of_driver = { + .probe = fpga_of_probe, + .remove = fpga_of_remove, + .driver = { + .name = drv_name, + .of_match_table = fpga_of_match, + .owner = THIS_MODULE, + }, +}; + +/* + * Module Init / Exit + */ + +static int __init fpga_init(void) +{ + led_trigger_register_simple("fpga", &ledtrig_fpga); + return of_register_platform_driver(&fpga_of_driver); +} + +static void __exit fpga_exit(void) +{ + of_unregister_platform_driver(&fpga_of_driver); + led_trigger_unregister_simple(ledtrig_fpga); +} + +MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>"); +MODULE_DESCRIPTION("CARMA Board DATA-FPGA Programmer"); +MODULE_LICENSE("GPL"); + +module_init(fpga_init); +module_exit(fpga_exit); |