drivers/fpga/socfpga-a10.c - SHIFTPHONES/mainline/linux - Gitiles

 /*
  * FPGA Manager Driver for Altera Arria10 SoCFPGA
  *
  * Copyright (C) 2015-2016 Altera Corporation
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope 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.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/clk.h>
 #include <linux/device.h>
 #include <linux/delay.h>
 #include <linux/fpga/fpga-mgr.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/regmap.h>

 #define A10_FPGAMGR_DCLKCNT_OFST				0x08
 #define A10_FPGAMGR_DCLKSTAT_OFST				0x0c
 #define A10_FPGAMGR_IMGCFG_CTL_00_OFST				0x70
 #define A10_FPGAMGR_IMGCFG_CTL_01_OFST				0x74
 #define A10_FPGAMGR_IMGCFG_CTL_02_OFST				0x78
 #define A10_FPGAMGR_IMGCFG_STAT_OFST				0x80

 #define A10_FPGAMGR_DCLKSTAT_DCLKDONE				BIT(0)

 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG		BIT(0)
 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS		BIT(1)
 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE		BIT(2)
 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG			BIT(8)
 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NSTATUS_OE		BIT(16)
 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_CONDONE_OE		BIT(24)

 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG		BIT(0)
 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST		BIT(16)
 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE			BIT(24)

 #define A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL			BIT(0)
 #define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK		(BIT(16) | BIT(17))
 #define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT			16
 #define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH			BIT(24)
 #define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT		24

 #define A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR			BIT(0)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_EARLY_USERMODE		BIT(1)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE			BIT(2)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN			BIT(4)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN			BIT(6)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY			BIT(9)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE			BIT(10)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR			BIT(11)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN			BIT(12)
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK	(BIT(16) | BIT(17) | BIT(18))
 #define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT		        16

 /* FPGA CD Ratio Value */
 #define CDRATIO_x1						0x0
 #define CDRATIO_x2						0x1
 #define CDRATIO_x4						0x2
 #define CDRATIO_x8						0x3

 /* Configuration width 16/32 bit */
 #define CFGWDTH_32						1
 #define CFGWDTH_16						0

 /*
  * struct a10_fpga_priv - private data for fpga manager
  * @regmap: regmap for register access
  * @fpga_data_addr: iomap for single address data register to FPGA
  * @clk: clock
  */
 struct a10_fpga_priv {
 	struct regmap *regmap;
 	void __iomem *fpga_data_addr;
 	struct clk *clk;
 };

 static bool socfpga_a10_fpga_writeable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case A10_FPGAMGR_DCLKCNT_OFST:
 	case A10_FPGAMGR_DCLKSTAT_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
 		return true;
 	}
 	return false;
 }

 static bool socfpga_a10_fpga_readable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case A10_FPGAMGR_DCLKCNT_OFST:
 	case A10_FPGAMGR_DCLKSTAT_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
 	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
 	case A10_FPGAMGR_IMGCFG_STAT_OFST:
 		return true;
 	}
 	return false;
 }

 static const struct regmap_config socfpga_a10_fpga_regmap_config = {
 	.reg_bits = 32,
 	.reg_stride = 4,
 	.val_bits = 32,
 	.writeable_reg = socfpga_a10_fpga_writeable_reg,
 	.readable_reg = socfpga_a10_fpga_readable_reg,
 	.max_register = A10_FPGAMGR_IMGCFG_STAT_OFST,
 	.cache_type = REGCACHE_NONE,
 };

 /*
  * from the register map description of cdratio in imgcfg_ctrl_02:
  *  Normal Configuration    : 32bit Passive Parallel
  *  Partial Reconfiguration : 16bit Passive Parallel
  */
 static void socfpga_a10_fpga_set_cfg_width(struct a10_fpga_priv *priv,
 					   int width)
 {
 	width <<= A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT;

 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH, width);
 }

 static void socfpga_a10_fpga_generate_dclks(struct a10_fpga_priv *priv,
 					    u32 count)
 {
 	u32 val;

 	/* Clear any existing DONE status. */
 	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
 		     A10_FPGAMGR_DCLKSTAT_DCLKDONE);

 	/* Issue the DCLK regmap. */
 	regmap_write(priv->regmap, A10_FPGAMGR_DCLKCNT_OFST, count);

 	/* wait till the dclkcnt done */
 	regmap_read_poll_timeout(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, val,
 				 val, 1, 100);

 	/* Clear DONE status. */
 	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
 		     A10_FPGAMGR_DCLKSTAT_DCLKDONE);
 }

 #define RBF_ENCRYPTION_MODE_OFFSET		69
 #define RBF_DECOMPRESS_OFFSET			229

 static int socfpga_a10_fpga_encrypted(u32 *buf32, size_t buf32_size)
 {
 	if (buf32_size < RBF_ENCRYPTION_MODE_OFFSET + 1)
 		return -EINVAL;

 	/* Is the bitstream encrypted? */
 	return ((buf32[RBF_ENCRYPTION_MODE_OFFSET] >> 2) & 3) != 0;
 }

 static int socfpga_a10_fpga_compressed(u32 *buf32, size_t buf32_size)
 {
 	if (buf32_size < RBF_DECOMPRESS_OFFSET + 1)
 		return -EINVAL;

 	/* Is the bitstream compressed? */
 	return !((buf32[RBF_DECOMPRESS_OFFSET] >> 1) & 1);
 }

 static unsigned int socfpga_a10_fpga_get_cd_ratio(unsigned int cfg_width,
 						  bool encrypt, bool compress)
 {
 	unsigned int cd_ratio;

 	/*
 	 * cd ratio is dependent on cfg width and whether the bitstream
 	 * is encrypted and/or compressed.
 	 *
 	 * | width | encr. | compr. | cd ratio |
 	 * |  16   |   0   |   0    |     1    |
 	 * |  16   |   0   |   1    |     4    |
 	 * |  16   |   1   |   0    |     2    |
 	 * |  16   |   1   |   1    |     4    |
 	 * |  32   |   0   |   0    |     1    |
 	 * |  32   |   0   |   1    |     8    |
 	 * |  32   |   1   |   0    |     4    |
 	 * |  32   |   1   |   1    |     8    |
 	 */
 	if (!compress && !encrypt)
 		return CDRATIO_x1;

 	if (compress)
 		cd_ratio = CDRATIO_x4;
 	else
 		cd_ratio = CDRATIO_x2;

 	/* If 32 bit, double the cd ratio by incrementing the field  */
 	if (cfg_width == CFGWDTH_32)
 		cd_ratio += 1;

 	return cd_ratio;
 }

 static int socfpga_a10_fpga_set_cdratio(struct fpga_manager *mgr,
 					unsigned int cfg_width,
 					const char *buf, size_t count)
 {
 	struct a10_fpga_priv *priv = mgr->priv;
 	unsigned int cd_ratio;
 	int encrypt, compress;

 	encrypt = socfpga_a10_fpga_encrypted((u32 *)buf, count / 4);
 	if (encrypt < 0)
 		return -EINVAL;

 	compress = socfpga_a10_fpga_compressed((u32 *)buf, count / 4);
 	if (compress < 0)
 		return -EINVAL;

 	cd_ratio = socfpga_a10_fpga_get_cd_ratio(cfg_width, encrypt, compress);

 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK,
 			   cd_ratio << A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT);

 	return 0;
 }

 static u32 socfpga_a10_fpga_read_stat(struct a10_fpga_priv *priv)
 {
 	u32 val;

 	regmap_read(priv->regmap, A10_FPGAMGR_IMGCFG_STAT_OFST, &val);

 	return val;
 }

 static int socfpga_a10_fpga_wait_for_pr_ready(struct a10_fpga_priv *priv)
 {
 	u32 reg, i;

 	for (i = 0; i < 10 ; i++) {
 		reg = socfpga_a10_fpga_read_stat(priv);

 		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
 			return -EINVAL;

 		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
 			return 0;
 	}

 	return -ETIMEDOUT;
 }

 static int socfpga_a10_fpga_wait_for_pr_done(struct a10_fpga_priv *priv)
 {
 	u32 reg, i;

 	for (i = 0; i < 10 ; i++) {
 		reg = socfpga_a10_fpga_read_stat(priv);

 		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
 			return -EINVAL;

 		if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE)
 			return 0;
 	}

 	return -ETIMEDOUT;
 }

 /* Start the FPGA programming by initialize the FPGA Manager */
 static int socfpga_a10_fpga_write_init(struct fpga_manager *mgr,
 				       struct fpga_image_info *info,
 				       const char *buf, size_t count)
 {
 	struct a10_fpga_priv *priv = mgr->priv;
 	unsigned int cfg_width;
 	u32 msel, stat, mask;
 	int ret;

 	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG)
 		cfg_width = CFGWDTH_16;
 	else
 		return -EINVAL;

 	/* Check for passive parallel (msel == 000 or 001) */
 	msel = socfpga_a10_fpga_read_stat(priv);
 	msel &= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK;
 	msel >>= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT;
 	if ((msel != 0) && (msel != 1)) {
 		dev_dbg(&mgr->dev, "Fail: invalid msel=%d\n", msel);
 		return -EINVAL;
 	}

 	/* Make sure no external devices are interfering */
 	stat = socfpga_a10_fpga_read_stat(priv);
 	mask = A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN |
 	       A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN;
 	if ((stat & mask) != mask)
 		return -EINVAL;

 	/* Set cfg width */
 	socfpga_a10_fpga_set_cfg_width(priv, cfg_width);

 	/* Determine cd ratio from bitstream header and set cd ratio */
 	ret = socfpga_a10_fpga_set_cdratio(mgr, cfg_width, buf, count);
 	if (ret)
 		return ret;

 	/*
 	 * Clear s2f_nce to enable chip select.  Leave pr_request
 	 * unasserted and override disabled.
 	 */
 	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 		     A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);

 	/* Set cfg_ctrl to enable s2f dclk and data */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL,
 			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL);

 	/*
 	 * Disable overrides not needed for pr.
 	 * s2f_config==1 leaves reset deasseted.
 	 */
 	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_00_OFST,
 		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG |
 		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS |
 		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE |
 		     A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG);

 	/* Enable override for data, dclk, nce, and pr_request to CSS */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG, 0);

 	/* Send some clocks to clear out any errors */
 	socfpga_a10_fpga_generate_dclks(priv, 256);

 	/* Assert pr_request */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST);

 	/* Provide 2048 DCLKs before starting the config data streaming. */
 	socfpga_a10_fpga_generate_dclks(priv, 0x7ff);

 	/* Wait for pr_ready */
 	return socfpga_a10_fpga_wait_for_pr_ready(priv);
 }

 /*
  * write data to the FPGA data register
  */
 static int socfpga_a10_fpga_write(struct fpga_manager *mgr, const char *buf,
 				  size_t count)
 {
 	struct a10_fpga_priv *priv = mgr->priv;
 	u32 *buffer_32 = (u32 *)buf;
 	size_t i = 0;

 	if (count <= 0)
 		return -EINVAL;

 	/* Write out the complete 32-bit chunks */
 	while (count >= sizeof(u32)) {
 		writel(buffer_32[i++], priv->fpga_data_addr);
 		count -= sizeof(u32);
 	}

 	/* Write out remaining non 32-bit chunks */
 	switch (count) {
 	case 3:
 		writel(buffer_32[i++] & 0x00ffffff, priv->fpga_data_addr);
 		break;
 	case 2:
 		writel(buffer_32[i++] & 0x0000ffff, priv->fpga_data_addr);
 		break;
 	case 1:
 		writel(buffer_32[i++] & 0x000000ff, priv->fpga_data_addr);
 		break;
 	case 0:
 		break;
 	default:
 		/* This will never happen */
 		return -EFAULT;
 	}

 	return 0;
 }

 static int socfpga_a10_fpga_write_complete(struct fpga_manager *mgr,
 					   struct fpga_image_info *info)
 {
 	struct a10_fpga_priv *priv = mgr->priv;
 	u32 reg;
 	int ret;

 	/* Wait for pr_done */
 	ret = socfpga_a10_fpga_wait_for_pr_done(priv);

 	/* Clear pr_request */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST, 0);

 	/* Send some clocks to clear out any errors */
 	socfpga_a10_fpga_generate_dclks(priv, 256);

 	/* Disable s2f dclk and data */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL, 0);

 	/* Deassert chip select */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE);

 	/* Disable data, dclk, nce, and pr_request override to CSS */
 	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG,
 			   A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);

 	/* Return any errors regarding pr_done or pr_error */
 	if (ret)
 		return ret;

 	/* Final check */
 	reg = socfpga_a10_fpga_read_stat(priv);

 	if (((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE) == 0) ||
 	    ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN) == 0) ||
 	    ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)) {
 		dev_dbg(&mgr->dev,
 			"Timeout in final check. Status=%08xf\n", reg);
 		return -ETIMEDOUT;
 	}

 	return 0;
 }

 static enum fpga_mgr_states socfpga_a10_fpga_state(struct fpga_manager *mgr)
 {
 	struct a10_fpga_priv *priv = mgr->priv;
 	u32 reg = socfpga_a10_fpga_read_stat(priv);

 	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE)
 		return FPGA_MGR_STATE_OPERATING;

 	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
 		return FPGA_MGR_STATE_WRITE;

 	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR)
 		return FPGA_MGR_STATE_WRITE_COMPLETE_ERR;

 	if ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)
 		return FPGA_MGR_STATE_RESET;

 	return FPGA_MGR_STATE_UNKNOWN;
 }

 static const struct fpga_manager_ops socfpga_a10_fpga_mgr_ops = {
 	.initial_header_size = (RBF_DECOMPRESS_OFFSET + 1) * 4,
 	.state = socfpga_a10_fpga_state,
 	.write_init = socfpga_a10_fpga_write_init,
 	.write = socfpga_a10_fpga_write,
 	.write_complete = socfpga_a10_fpga_write_complete,
 };

 static int socfpga_a10_fpga_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct a10_fpga_priv *priv;
 	void __iomem *reg_base;
 	struct fpga_manager *mgr;
 	struct resource *res;
 	int ret;

 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	/* First mmio base is for register access */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	reg_base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(reg_base))
 		return PTR_ERR(reg_base);

 	/* Second mmio base is for writing FPGA image data */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	priv->fpga_data_addr = devm_ioremap_resource(dev, res);
 	if (IS_ERR(priv->fpga_data_addr))
 		return PTR_ERR(priv->fpga_data_addr);

 	/* regmap for register access */
 	priv->regmap = devm_regmap_init_mmio(dev, reg_base,
 					     &socfpga_a10_fpga_regmap_config);
 	if (IS_ERR(priv->regmap))
 		return -ENODEV;

 	priv->clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(priv->clk)) {
 		dev_err(dev, "no clock specified\n");
 		return PTR_ERR(priv->clk);
 	}

 	ret = clk_prepare_enable(priv->clk);
 	if (ret) {
 		dev_err(dev, "could not enable clock\n");
 		return -EBUSY;
 	}

 	mgr = fpga_mgr_create(dev, "SoCFPGA Arria10 FPGA Manager",
 			      &socfpga_a10_fpga_mgr_ops, priv);
 	if (!mgr)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, mgr);

 	ret = fpga_mgr_register(mgr);
 	if (ret) {
 		fpga_mgr_free(mgr);
 		clk_disable_unprepare(priv->clk);
 		return ret;
 	}

 	return 0;
 }

 static int socfpga_a10_fpga_remove(struct platform_device *pdev)
 {
 	struct fpga_manager *mgr = platform_get_drvdata(pdev);
 	struct a10_fpga_priv *priv = mgr->priv;

 	fpga_mgr_unregister(mgr);
 	clk_disable_unprepare(priv->clk);

 	return 0;
 }

 static const struct of_device_id socfpga_a10_fpga_of_match[] = {
 	{ .compatible = "altr,socfpga-a10-fpga-mgr", },
 	{},
 };

 MODULE_DEVICE_TABLE(of, socfpga_a10_fpga_of_match);

 static struct platform_driver socfpga_a10_fpga_driver = {
 	.probe = socfpga_a10_fpga_probe,
 	.remove = socfpga_a10_fpga_remove,
 	.driver = {
 		.name	= "socfpga_a10_fpga_manager",
 		.of_match_table = socfpga_a10_fpga_of_match,
 	},
 };

 module_platform_driver(socfpga_a10_fpga_driver);

 MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
 MODULE_DESCRIPTION("SoCFPGA Arria10 FPGA Manager");
 MODULE_LICENSE("GPL v2");
	/*
	* FPGA Manager Driver for Altera Arria10 SoCFPGA
	*
	* Copyright (C) 2015-2016 Altera Corporation
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope 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.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/clk.h>
	#include <linux/device.h>
	#include <linux/delay.h>
	#include <linux/fpga/fpga-mgr.h>
	#include <linux/io.h>
	#include <linux/module.h>
	#include <linux/of_address.h>
	#include <linux/regmap.h>

	#define A10_FPGAMGR_DCLKCNT_OFST 0x08
	#define A10_FPGAMGR_DCLKSTAT_OFST 0x0c
	#define A10_FPGAMGR_IMGCFG_CTL_00_OFST 0x70
	#define A10_FPGAMGR_IMGCFG_CTL_01_OFST 0x74
	#define A10_FPGAMGR_IMGCFG_CTL_02_OFST 0x78
	#define A10_FPGAMGR_IMGCFG_STAT_OFST 0x80

	#define A10_FPGAMGR_DCLKSTAT_DCLKDONE BIT(0)

	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG BIT(0)
	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS BIT(1)
	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE BIT(2)
	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG BIT(8)
	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NSTATUS_OE BIT(16)
	#define A10_FPGAMGR_IMGCFG_CTL_00_S2F_CONDONE_OE BIT(24)

	#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG BIT(0)
	#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST BIT(16)
	#define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE BIT(24)

	#define A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL BIT(0)
	#define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK (BIT(16) \| BIT(17))
	#define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT 16
	#define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH BIT(24)
	#define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT 24

	#define A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR BIT(0)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_EARLY_USERMODE BIT(1)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE BIT(2)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN BIT(4)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN BIT(6)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY BIT(9)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE BIT(10)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR BIT(11)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN BIT(12)
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK (BIT(16) \| BIT(17) \| BIT(18))
	#define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT 16

	/* FPGA CD Ratio Value */
	#define CDRATIO_x1 0x0
	#define CDRATIO_x2 0x1
	#define CDRATIO_x4 0x2
	#define CDRATIO_x8 0x3

	/* Configuration width 16/32 bit */
	#define CFGWDTH_32 1
	#define CFGWDTH_16 0

	/*
	* struct a10_fpga_priv - private data for fpga manager
	* @regmap: regmap for register access
	* @fpga_data_addr: iomap for single address data register to FPGA
	* @clk: clock
	*/
	struct a10_fpga_priv {
	struct regmap *regmap;
	void __iomem *fpga_data_addr;
	struct clk *clk;
	};

	static bool socfpga_a10_fpga_writeable_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case A10_FPGAMGR_DCLKCNT_OFST:
	case A10_FPGAMGR_DCLKSTAT_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
	return true;
	}
	return false;
	}

	static bool socfpga_a10_fpga_readable_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case A10_FPGAMGR_DCLKCNT_OFST:
	case A10_FPGAMGR_DCLKSTAT_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_00_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_01_OFST:
	case A10_FPGAMGR_IMGCFG_CTL_02_OFST:
	case A10_FPGAMGR_IMGCFG_STAT_OFST:
	return true;
	}
	return false;
	}

	static const struct regmap_config socfpga_a10_fpga_regmap_config = {
	.reg_bits = 32,
	.reg_stride = 4,
	.val_bits = 32,
	.writeable_reg = socfpga_a10_fpga_writeable_reg,
	.readable_reg = socfpga_a10_fpga_readable_reg,
	.max_register = A10_FPGAMGR_IMGCFG_STAT_OFST,
	.cache_type = REGCACHE_NONE,
	};

	/*
	* from the register map description of cdratio in imgcfg_ctrl_02:
	* Normal Configuration : 32bit Passive Parallel
	* Partial Reconfiguration : 16bit Passive Parallel
	*/
	static void socfpga_a10_fpga_set_cfg_width(struct a10_fpga_priv *priv,
	int width)
	{
	width <<= A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT;

	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
	A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH, width);
	}

	static void socfpga_a10_fpga_generate_dclks(struct a10_fpga_priv *priv,
	u32 count)
	{
	u32 val;

	/* Clear any existing DONE status. */
	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
	A10_FPGAMGR_DCLKSTAT_DCLKDONE);

	/* Issue the DCLK regmap. */
	regmap_write(priv->regmap, A10_FPGAMGR_DCLKCNT_OFST, count);

	/* wait till the dclkcnt done */
	regmap_read_poll_timeout(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, val,
	val, 1, 100);

	/* Clear DONE status. */
	regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST,
	A10_FPGAMGR_DCLKSTAT_DCLKDONE);
	}

	#define RBF_ENCRYPTION_MODE_OFFSET 69
	#define RBF_DECOMPRESS_OFFSET 229

	static int socfpga_a10_fpga_encrypted(u32 *buf32, size_t buf32_size)
	{
	if (buf32_size < RBF_ENCRYPTION_MODE_OFFSET + 1)
	return -EINVAL;

	/* Is the bitstream encrypted? */
	return ((buf32[RBF_ENCRYPTION_MODE_OFFSET] >> 2) & 3) != 0;
	}

	static int socfpga_a10_fpga_compressed(u32 *buf32, size_t buf32_size)
	{
	if (buf32_size < RBF_DECOMPRESS_OFFSET + 1)
	return -EINVAL;

	/* Is the bitstream compressed? */
	return !((buf32[RBF_DECOMPRESS_OFFSET] >> 1) & 1);
	}

	static unsigned int socfpga_a10_fpga_get_cd_ratio(unsigned int cfg_width,
	bool encrypt, bool compress)
	{
	unsigned int cd_ratio;

	/*
	* cd ratio is dependent on cfg width and whether the bitstream
	* is encrypted and/or compressed.
	*
	* \| width \| encr. \| compr. \| cd ratio \|
	* \| 16 \| 0 \| 0 \| 1 \|
	* \| 16 \| 0 \| 1 \| 4 \|
	* \| 16 \| 1 \| 0 \| 2 \|
	* \| 16 \| 1 \| 1 \| 4 \|
	* \| 32 \| 0 \| 0 \| 1 \|
	* \| 32 \| 0 \| 1 \| 8 \|
	* \| 32 \| 1 \| 0 \| 4 \|
	* \| 32 \| 1 \| 1 \| 8 \|
	*/
	if (!compress && !encrypt)
	return CDRATIO_x1;

	if (compress)
	cd_ratio = CDRATIO_x4;
	else
	cd_ratio = CDRATIO_x2;

	/* If 32 bit, double the cd ratio by incrementing the field */
	if (cfg_width == CFGWDTH_32)
	cd_ratio += 1;

	return cd_ratio;
	}

	static int socfpga_a10_fpga_set_cdratio(struct fpga_manager *mgr,
	unsigned int cfg_width,
	const char *buf, size_t count)
	{
	struct a10_fpga_priv *priv = mgr->priv;
	unsigned int cd_ratio;
	int encrypt, compress;

	encrypt = socfpga_a10_fpga_encrypted((u32 *)buf, count / 4);
	if (encrypt < 0)
	return -EINVAL;

	compress = socfpga_a10_fpga_compressed((u32 *)buf, count / 4);
	if (compress < 0)
	return -EINVAL;

	cd_ratio = socfpga_a10_fpga_get_cd_ratio(cfg_width, encrypt, compress);

	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
	A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK,
	cd_ratio << A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT);

	return 0;
	}

	static u32 socfpga_a10_fpga_read_stat(struct a10_fpga_priv *priv)
	{
	u32 val;

	regmap_read(priv->regmap, A10_FPGAMGR_IMGCFG_STAT_OFST, &val);

	return val;
	}

	static int socfpga_a10_fpga_wait_for_pr_ready(struct a10_fpga_priv *priv)
	{
	u32 reg, i;

	for (i = 0; i < 10 ; i++) {
	reg = socfpga_a10_fpga_read_stat(priv);

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
	return -EINVAL;

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
	return 0;
	}

	return -ETIMEDOUT;
	}

	static int socfpga_a10_fpga_wait_for_pr_done(struct a10_fpga_priv *priv)
	{
	u32 reg, i;

	for (i = 0; i < 10 ; i++) {
	reg = socfpga_a10_fpga_read_stat(priv);

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR)
	return -EINVAL;

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE)
	return 0;
	}

	return -ETIMEDOUT;
	}

	/* Start the FPGA programming by initialize the FPGA Manager */
	static int socfpga_a10_fpga_write_init(struct fpga_manager *mgr,
	struct fpga_image_info *info,
	const char *buf, size_t count)
	{
	struct a10_fpga_priv *priv = mgr->priv;
	unsigned int cfg_width;
	u32 msel, stat, mask;
	int ret;

	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG)
	cfg_width = CFGWDTH_16;
	else
	return -EINVAL;

	/* Check for passive parallel (msel == 000 or 001) */
	msel = socfpga_a10_fpga_read_stat(priv);
	msel &= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK;
	msel >>= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT;
	if ((msel != 0) && (msel != 1)) {
	dev_dbg(&mgr->dev, "Fail: invalid msel=%d\n", msel);
	return -EINVAL;
	}

	/* Make sure no external devices are interfering */
	stat = socfpga_a10_fpga_read_stat(priv);
	mask = A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN \|
	A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN;
	if ((stat & mask) != mask)
	return -EINVAL;

	/* Set cfg width */
	socfpga_a10_fpga_set_cfg_width(priv, cfg_width);

	/* Determine cd ratio from bitstream header and set cd ratio */
	ret = socfpga_a10_fpga_set_cdratio(mgr, cfg_width, buf, count);
	if (ret)
	return ret;

	/*
	* Clear s2f_nce to enable chip select. Leave pr_request
	* unasserted and override disabled.
	*/
	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);

	/* Set cfg_ctrl to enable s2f dclk and data */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
	A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL,
	A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL);

	/*
	* Disable overrides not needed for pr.
	* s2f_config==1 leaves reset deasseted.
	*/
	regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_00_OFST,
	A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG \|
	A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS \|
	A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE \|
	A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG);

	/* Enable override for data, dclk, nce, and pr_request to CSS */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG, 0);

	/* Send some clocks to clear out any errors */
	socfpga_a10_fpga_generate_dclks(priv, 256);

	/* Assert pr_request */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST);

	/* Provide 2048 DCLKs before starting the config data streaming. */
	socfpga_a10_fpga_generate_dclks(priv, 0x7ff);

	/* Wait for pr_ready */
	return socfpga_a10_fpga_wait_for_pr_ready(priv);
	}

	/*
	* write data to the FPGA data register
	*/
	static int socfpga_a10_fpga_write(struct fpga_manager mgr, const char buf,
	size_t count)
	{
	struct a10_fpga_priv *priv = mgr->priv;
	u32 buffer_32 = (u32 )buf;
	size_t i = 0;

	if (count <= 0)
	return -EINVAL;

	/* Write out the complete 32-bit chunks */
	while (count >= sizeof(u32)) {
	writel(buffer_32[i++], priv->fpga_data_addr);
	count -= sizeof(u32);
	}

	/* Write out remaining non 32-bit chunks */
	switch (count) {
	case 3:
	writel(buffer_32[i++] & 0x00ffffff, priv->fpga_data_addr);
	break;
	case 2:
	writel(buffer_32[i++] & 0x0000ffff, priv->fpga_data_addr);
	break;
	case 1:
	writel(buffer_32[i++] & 0x000000ff, priv->fpga_data_addr);
	break;
	case 0:
	break;
	default:
	/* This will never happen */
	return -EFAULT;
	}

	return 0;
	}

	static int socfpga_a10_fpga_write_complete(struct fpga_manager *mgr,
	struct fpga_image_info *info)
	{
	struct a10_fpga_priv *priv = mgr->priv;
	u32 reg;
	int ret;

	/* Wait for pr_done */
	ret = socfpga_a10_fpga_wait_for_pr_done(priv);

	/* Clear pr_request */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST, 0);

	/* Send some clocks to clear out any errors */
	socfpga_a10_fpga_generate_dclks(priv, 256);

	/* Disable s2f dclk and data */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST,
	A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL, 0);

	/* Deassert chip select */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE);

	/* Disable data, dclk, nce, and pr_request override to CSS */
	regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG,
	A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG);

	/* Return any errors regarding pr_done or pr_error */
	if (ret)
	return ret;

	/* Final check */
	reg = socfpga_a10_fpga_read_stat(priv);

	if (((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE) == 0) \|\|
	((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN) == 0) \|\|
	((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)) {
	dev_dbg(&mgr->dev,
	"Timeout in final check. Status=%08xf\n", reg);
	return -ETIMEDOUT;
	}

	return 0;
	}

	static enum fpga_mgr_states socfpga_a10_fpga_state(struct fpga_manager *mgr)
	{
	struct a10_fpga_priv *priv = mgr->priv;
	u32 reg = socfpga_a10_fpga_read_stat(priv);

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE)
	return FPGA_MGR_STATE_OPERATING;

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY)
	return FPGA_MGR_STATE_WRITE;

	if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR)
	return FPGA_MGR_STATE_WRITE_COMPLETE_ERR;

	if ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)
	return FPGA_MGR_STATE_RESET;

	return FPGA_MGR_STATE_UNKNOWN;
	}

	static const struct fpga_manager_ops socfpga_a10_fpga_mgr_ops = {
	.initial_header_size = (RBF_DECOMPRESS_OFFSET + 1) * 4,
	.state = socfpga_a10_fpga_state,
	.write_init = socfpga_a10_fpga_write_init,
	.write = socfpga_a10_fpga_write,
	.write_complete = socfpga_a10_fpga_write_complete,
	};

	static int socfpga_a10_fpga_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct a10_fpga_priv *priv;
	void __iomem *reg_base;
	struct fpga_manager *mgr;
	struct resource *res;
	int ret;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	/* First mmio base is for register access */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	reg_base = devm_ioremap_resource(dev, res);
	if (IS_ERR(reg_base))
	return PTR_ERR(reg_base);

	/* Second mmio base is for writing FPGA image data */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	priv->fpga_data_addr = devm_ioremap_resource(dev, res);
	if (IS_ERR(priv->fpga_data_addr))
	return PTR_ERR(priv->fpga_data_addr);

	/* regmap for register access */
	priv->regmap = devm_regmap_init_mmio(dev, reg_base,
	&socfpga_a10_fpga_regmap_config);
	if (IS_ERR(priv->regmap))
	return -ENODEV;

	priv->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(priv->clk)) {
	dev_err(dev, "no clock specified\n");
	return PTR_ERR(priv->clk);
	}

	ret = clk_prepare_enable(priv->clk);
	if (ret) {
	dev_err(dev, "could not enable clock\n");
	return -EBUSY;
	}

	mgr = fpga_mgr_create(dev, "SoCFPGA Arria10 FPGA Manager",
	&socfpga_a10_fpga_mgr_ops, priv);
	if (!mgr)
	return -ENOMEM;

	platform_set_drvdata(pdev, mgr);

	ret = fpga_mgr_register(mgr);
	if (ret) {
	fpga_mgr_free(mgr);
	clk_disable_unprepare(priv->clk);
	return ret;
	}

	return 0;
	}

	static int socfpga_a10_fpga_remove(struct platform_device *pdev)
	{
	struct fpga_manager *mgr = platform_get_drvdata(pdev);
	struct a10_fpga_priv *priv = mgr->priv;

	fpga_mgr_unregister(mgr);
	clk_disable_unprepare(priv->clk);

	return 0;
	}

	static const struct of_device_id socfpga_a10_fpga_of_match[] = {
	{ .compatible = "altr,socfpga-a10-fpga-mgr", },
	{},
	};

	MODULE_DEVICE_TABLE(of, socfpga_a10_fpga_of_match);

	static struct platform_driver socfpga_a10_fpga_driver = {
	.probe = socfpga_a10_fpga_probe,
	.remove = socfpga_a10_fpga_remove,
	.driver = {
	.name = "socfpga_a10_fpga_manager",
	.of_match_table = socfpga_a10_fpga_of_match,
	},
	};

	module_platform_driver(socfpga_a10_fpga_driver);

	MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
	MODULE_DESCRIPTION("SoCFPGA Arria10 FPGA Manager");
	MODULE_LICENSE("GPL v2");