path: root/drivers/misc/carma/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_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