https://github.com/torvalds/linux
Tip revision: e26081808edadfd257c6c9d81014e3b25e9a6118 authored by Linus Torvalds on 18 May 2015, 17:13:47 UTC
Linux 4.1-rc4
Linux 4.1-rc4
Tip revision: e260818
carma-fpga-program.c
/*
* 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_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/completion.h>
#include <linux/miscdevice.h>
#include <linux/dmaengine.h>
#include <linux/fsldma.h>
#include <linux/interrupt.h>
#include <linux/highmem.h>
#include <linux/vmalloc.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>
/* 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;
void *vaddr;
struct scatterlist *sglist;
int sglen;
int nr_pages;
bool buf_allocated;
/* max size and written bytes */
size_t fw_size;
size_t bytes;
};
static int fpga_dma_init(struct fpga_dev *priv, int nr_pages)
{
struct page *pg;
int i;
priv->vaddr = vmalloc_32(nr_pages << PAGE_SHIFT);
if (NULL == priv->vaddr) {
pr_debug("vmalloc_32(%d pages) failed\n", nr_pages);
return -ENOMEM;
}
pr_debug("vmalloc is at addr 0x%08lx, size=%d\n",
(unsigned long)priv->vaddr,
nr_pages << PAGE_SHIFT);
memset(priv->vaddr, 0, nr_pages << PAGE_SHIFT);
priv->nr_pages = nr_pages;
priv->sglist = vzalloc(priv->nr_pages * sizeof(*priv->sglist));
if (NULL == priv->sglist)
goto vzalloc_err;
sg_init_table(priv->sglist, priv->nr_pages);
for (i = 0; i < priv->nr_pages; i++) {
pg = vmalloc_to_page(priv->vaddr + i * PAGE_SIZE);
if (NULL == pg)
goto vmalloc_to_page_err;
sg_set_page(&priv->sglist[i], pg, PAGE_SIZE, 0);
}
return 0;
vmalloc_to_page_err:
vfree(priv->sglist);
priv->sglist = NULL;
vzalloc_err:
vfree(priv->vaddr);
priv->vaddr = NULL;
return -ENOMEM;
}
static int fpga_dma_map(struct fpga_dev *priv)
{
priv->sglen = dma_map_sg(priv->dev, priv->sglist,
priv->nr_pages, DMA_TO_DEVICE);
if (0 == priv->sglen) {
pr_warn("%s: dma_map_sg failed\n", __func__);
return -ENOMEM;
}
return 0;
}
static int fpga_dma_unmap(struct fpga_dev *priv)
{
if (!priv->sglen)
return 0;
dma_unmap_sg(priv->dev, priv->sglist, priv->sglen, DMA_TO_DEVICE);
priv->sglen = 0;
return 0;
}
/*
* 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)
{
vfree(priv->sglist);
vfree(priv->vaddr);
priv->buf_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;
unsigned long timeout;
/* 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->vaddr, priv->bytes);
if (ret)
goto out_disable_controller;
/* Wait for the interrupt handler to signal that programming finished */
timeout = wait_for_completion_timeout(&priv->completion, 2 * HZ);
if (!timeout) {
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 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;
unsigned long timeout;
/* 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 = fpga_dma_map(priv);
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_MEM_TO_DEV;
config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
config.dst_maxburst = fpga_fifo_size(priv->regs) / 2 / 4;
ret = dmaengine_slave_config(chan, &config);
if (ret) {
dev_err(priv->dev, "DMA slave configuration failed\n");
goto out_dma_unmap;
}
ret = fsl_dma_external_start(chan, 1);
if (ret) {
dev_err(priv->dev, "DMA external control setup failed\n");
goto out_dma_unmap;
}
/* setup and submit the DMA transaction */
tx = dmaengine_prep_dma_sg(chan, table.sgl, num_pages,
priv->sglist, priv->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_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 */
timeout = wait_for_completion_timeout(&priv->completion, 2 * HZ);
if (!timeout) {
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:
fpga_dma_unmap(priv);
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->buf_allocated)
return 0;
/* Allocate a buffer to hold enough data for the bitfile */
nr_pages = DIV_ROUND_UP(priv->fw_size, PAGE_SIZE);
ret = fpga_dma_init(priv, 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->buf_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->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;
return simple_read_from_buffer(buf, count, f_pos,
priv->vaddr, priv->bytes);
}
static loff_t fpga_llseek(struct file *filp, loff_t offset, int origin)
{
struct fpga_dev *priv = filp->private_data;
/* only read-only opens are allowed to seek */
if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
return -EINVAL;
return fixed_size_llseek(filp, offset, origin, priv->fw_size);
}
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;
ret = kstrtoul(buf, 0, &val);
if (ret)
return ret;
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;
ret = kstrtoul(buf, 0, &val);
if (ret)
return ret;
/* 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 = platform_get_drvdata(op);
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)
{
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);
platform_set_drvdata(op, priv);
priv->dev = &op->dev;
mutex_init(&priv->lock);
init_completion(&priv->completion);
dev_set_drvdata(priv->dev, priv);
dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, 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 const struct of_device_id fpga_of_match[] = {
{ .compatible = "carma,fpga-programmer", },
{},
};
static struct platform_driver fpga_of_driver = {
.probe = fpga_of_probe,
.remove = fpga_of_remove,
.driver = {
.name = drv_name,
.of_match_table = fpga_of_match,
},
};
/*
* Module Init / Exit
*/
static int __init fpga_init(void)
{
led_trigger_register_simple("fpga", &ledtrig_fpga);
return platform_driver_register(&fpga_of_driver);
}
static void __exit fpga_exit(void)
{
platform_driver_unregister(&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);