Date: Thu, 18 Dec 2014 16:31:27 +0100
From: Michal Simek <michal.simek@xilinx.com>
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CC: <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
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        <delicious.quinoa@gmail.com>, <dinguyen@opensource.altera.com>,
        <yvanderv@opensource.altera.com>
Subject: Re: [PATCH v5 4/6] staging: fpga manager: add driver for socfpga
 fpga manager
References: <1418835289-15752-1-git-send-email-atull@opensource.altera.com>
 <1418835289-15752-5-git-send-email-atull@opensource.altera.com>
In-Reply-To: <1418835289-15752-5-git-send-email-atull@opensource.altera.com>
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Sender: linux-kernel-owner@vger.kernel.org

On 12/17/2014 05:54 PM, atull@opensource.altera.com wrote:
> From: Alan Tull <atull@opensource.altera.com>
> 
> Add driver to fpga manager framework to allow configuration
> of FPGA in Altera SoCFPGA parts.
> 
> Signed-off-by: Alan Tull <atull@opensource.altera.com>
> ---
> v2: fpga_manager struct now contains struct device
>     fpga_manager_register parameters now take device
> 
> v3: skip a version to align versions
> 
> v4: move to drivers/staging
> 
> v5: fix array_size.cocci warnings
>     fix platform_no_drv_owner.cocci warnings
>     Remove .owner = THIS_MODULE
>     include asm/irq.h
>     clean up list of includes
>     use altera_fpga_reset for ops
>     use enum fpga_mgr_states or u32 as needed
>     use devm_request_irq
>     check irq <= 0 instead of == NO_IRQ
>     Use ARRAY_SIZE
>     rename altera -> socfpga
>     static const socfpga_fpga_ops
>     header moved to linux/fpga/ folder
>     remove ifdef'ed code
>     use platform_get_resource and platform_get_irq
>     move .probe and .remove lines adjacent
>     use module_platform_driver
>     use __maybe_unused
>     only need to 'if (IS_ENABLED(CONFIG_REGULATOR))' in one fn
>     fix "unsigned 'mode' is never < 0"
> ---
>  drivers/staging/fpga/Kconfig   |    5 +
>  drivers/staging/fpga/Makefile  |    1 +
>  drivers/staging/fpga/socfpga.c |  692 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 698 insertions(+)
>  create mode 100644 drivers/staging/fpga/socfpga.c
> 
> diff --git a/drivers/staging/fpga/Kconfig b/drivers/staging/fpga/Kconfig
> index 89ebafc..ce17342 100644
> --- a/drivers/staging/fpga/Kconfig
> +++ b/drivers/staging/fpga/Kconfig
> @@ -19,6 +19,11 @@ config FPGA_MGR_SYSFS
>  	help
>  	  FPGA Manager SysFS interface.
>  
> +config FPGA_MGR_SOCFPGA
> +	tristate "Altera SOCFPGA"
> +	help
> +	  FPGA manager driver support for Altera SOCFPGA.
> +
>  endif # FPGA
>  
>  endmenu
> diff --git a/drivers/staging/fpga/Makefile b/drivers/staging/fpga/Makefile
> index ff6c677..97f7751 100644
> --- a/drivers/staging/fpga/Makefile
> +++ b/drivers/staging/fpga/Makefile
> @@ -8,3 +8,4 @@ fpga-mgr-core-y += fpga-mgr.o
>  obj-$(CONFIG_FPGA)			+= fpga-mgr.o
>  
>  # FPGA Manager Drivers
> +obj-$(CONFIG_FPGA_MGR_SOCFPGA)		+= socfpga.o
> diff --git a/drivers/staging/fpga/socfpga.c b/drivers/staging/fpga/socfpga.c
> new file mode 100644
> index 0000000..ad9e99f
> --- /dev/null
> +++ b/drivers/staging/fpga/socfpga.c
> @@ -0,0 +1,692 @@
> +/*
> + * FPGA Manager Driver for Altera SOCFPGA
> + *
> + *  Copyright (C) 2013-2014 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/completion.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/of_irq.h>
> +#include <linux/pm.h>
> +#include <linux/string.h>
> +#include <linux/regulator/consumer.h>
> +
> +/* Register offsets */
> +#define SOCFPGA_FPGMGR_STAT_OFST				0x0
> +#define SOCFPGA_FPGMGR_CTL_OFST					0x4
> +#define SOCFPGA_FPGMGR_DCLKCNT_OFST				0x8
> +#define SOCFPGA_FPGMGR_DCLKSTAT_OFST				0xc
> +#define SOCFPGA_FPGMGR_GPIO_INTEN_OFST				0x830
> +#define SOCFPGA_FPGMGR_GPIO_INTMSK_OFST				0x834
> +#define SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST			0x838
> +#define SOCFPGA_FPGMGR_GPIO_INT_POL_OFST			0x83c
> +#define SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST			0x840
> +#define SOCFPGA_FPGMGR_GPIO_RAW_INTSTAT_OFST			0x844
> +#define SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST			0x84c
> +#define SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST			0x850
> +
> +/* Register bit defines */
> +/* SOCFPGA_FPGMGR_STAT register mode field values */
> +#define SOCFPGA_FPGMGR_STAT_POWER_UP				0x0 /*ramping*/
> +#define SOCFPGA_FPGMGR_STAT_RESET				0x1
> +#define SOCFPGA_FPGMGR_STAT_CFG					0x2
> +#define SOCFPGA_FPGMGR_STAT_INIT				0x3
> +#define SOCFPGA_FPGMGR_STAT_USER_MODE				0x4
> +#define SOCFPGA_FPGMGR_STAT_UNKNOWN				0x5
> +#define SOCFPGA_FPGMGR_STAT_STATE_MASK				0x7
> +/* This is a flag value that doesn't really happen in this register field */
> +#define SOCFPGA_FPGMGR_STAT_POWER_OFF				0x0
> +
> +#define MSEL_PP16_FAST_NOAES_NODC				0x0
> +#define MSEL_PP16_FAST_AES_NODC					0x1
> +#define MSEL_PP16_FAST_AESOPT_DC				0x2
> +#define MSEL_PP16_SLOW_NOAES_NODC				0x4
> +#define MSEL_PP16_SLOW_AES_NODC					0x5
> +#define MSEL_PP16_SLOW_AESOPT_DC				0x6
> +#define MSEL_PP32_FAST_NOAES_NODC				0x8
> +#define MSEL_PP32_FAST_AES_NODC					0x9
> +#define MSEL_PP32_FAST_AESOPT_DC				0xa
> +#define MSEL_PP32_SLOW_NOAES_NODC				0xc
> +#define MSEL_PP32_SLOW_AES_NODC					0xd
> +#define MSEL_PP32_SLOW_AESOPT_DC				0xe
> +#define SOCFPGA_FPGMGR_STAT_MSEL_MASK				0x000000f8
> +#define SOCFPGA_FPGMGR_STAT_MSEL_SHIFT				3
> +
> +/* SOCFPGA_FPGMGR_CTL register */
> +#define SOCFPGA_FPGMGR_CTL_EN					0x00000001
> +#define SOCFPGA_FPGMGR_CTL_NCE					0x00000002
> +#define SOCFPGA_FPGMGR_CTL_NCFGPULL				0x00000004
> +
> +#define CDRATIO_X1						0x00000000
> +#define CDRATIO_X2						0x00000040
> +#define CDRATIO_X4						0x00000080
> +#define CDRATIO_X8						0x000000c0
> +#define SOCFPGA_FPGMGR_CTL_CDRATIO_MASK				0x000000c0
> +
> +#define SOCFPGA_FPGMGR_CTL_AXICFGEN				0x00000100
> +
> +#define CFGWDTH_16						0x00000000
> +#define CFGWDTH_32						0x00000200
> +#define SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK				0x00000200
> +
> +/* SOCFPGA_FPGMGR_DCLKSTAT register */
> +#define SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE			0x1
> +
> +/* SOCFPGA_FPGMGR_GPIO_* registers share the same bit positions */
> +#define SOCFPGA_FPGMGR_MON_NSTATUS				0x0001
> +#define SOCFPGA_FPGMGR_MON_CONF_DONE				0x0002
> +#define SOCFPGA_FPGMGR_MON_INIT_DONE				0x0004
> +#define SOCFPGA_FPGMGR_MON_CRC_ERROR				0x0008
> +#define SOCFPGA_FPGMGR_MON_CVP_CONF_DONE			0x0010
> +#define SOCFPGA_FPGMGR_MON_PR_READY				0x0020
> +#define SOCFPGA_FPGMGR_MON_PR_ERROR				0x0040
> +#define SOCFPGA_FPGMGR_MON_PR_DONE				0x0080
> +#define SOCFPGA_FPGMGR_MON_NCONFIG_PIN				0x0100
> +#define SOCFPGA_FPGMGR_MON_NSTATUS_PIN				0x0200
> +#define SOCFPGA_FPGMGR_MON_CONF_DONE_PIN			0x0400
> +#define SOCFPGA_FPGMGR_MON_FPGA_POWER_ON			0x0800
> +#define SOCFPGA_FPGMGR_MON_STATUS_MASK				0x0fff
> +
> +#define SOCFPGA_FPGMGR_NUM_SUPPLIES 3
> +#define SOCFPGA_RESUME_TIMEOUT 3
> +
> +/* In power-up order. Reverse for power-down. */
> +static const char *supply_names[SOCFPGA_FPGMGR_NUM_SUPPLIES] __maybe_unused = {
> +	"FPGA-1.5V",
> +	"FPGA-1.1V",
> +	"FPGA-2.5V",
> +};
> +
> +struct socfpga_fpga_priv {
> +	void __iomem *fpga_base_addr;
> +	void __iomem *fpga_data_addr;
> +	struct completion status_complete;
> +	int irq;
> +	struct regulator *fpga_supplies[SOCFPGA_FPGMGR_NUM_SUPPLIES];
> +};
> +
> +struct cfgmgr_mode {
> +	/* Values to set in the CTRL register */
> +	u32 ctrl;
> +
> +	/* flag that this table entry is a valid mode */
> +	bool valid;
> +};
> +
> +/* For SOCFPGA_FPGMGR_STAT_MSEL field */
> +static struct cfgmgr_mode cfgmgr_modes[] = {
> +	[MSEL_PP16_FAST_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
> +	[MSEL_PP16_FAST_AES_NODC] =   { CFGWDTH_16 | CDRATIO_X2, 1 },
> +	[MSEL_PP16_FAST_AESOPT_DC] =  { CFGWDTH_16 | CDRATIO_X4, 1 },
> +	[MSEL_PP16_SLOW_NOAES_NODC] = { CFGWDTH_16 | CDRATIO_X1, 1 },
> +	[MSEL_PP16_SLOW_AES_NODC] =   { CFGWDTH_16 | CDRATIO_X2, 1 },
> +	[MSEL_PP16_SLOW_AESOPT_DC] =  { CFGWDTH_16 | CDRATIO_X4, 1 },
> +	[MSEL_PP32_FAST_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
> +	[MSEL_PP32_FAST_AES_NODC] =   { CFGWDTH_32 | CDRATIO_X4, 1 },
> +	[MSEL_PP32_FAST_AESOPT_DC] =  { CFGWDTH_32 | CDRATIO_X8, 1 },
> +	[MSEL_PP32_SLOW_NOAES_NODC] = { CFGWDTH_32 | CDRATIO_X1, 1 },
> +	[MSEL_PP32_SLOW_AES_NODC] =   { CFGWDTH_32 | CDRATIO_X4, 1 },
> +	[MSEL_PP32_SLOW_AESOPT_DC] =  { CFGWDTH_32 | CDRATIO_X8, 1 },
> +};
> +
> +static u32 socfpga_fpga_readl(struct socfpga_fpga_priv *priv, u32 reg_offset)
> +{
> +	return readl(priv->fpga_base_addr + reg_offset);
> +}
> +
> +static void socfpga_fpga_writel(struct socfpga_fpga_priv *priv, u32 reg_offset,
> +				u32 value)
> +{
> +	writel(value, priv->fpga_base_addr + reg_offset);
> +}
> +
> +static u32 socfpga_fpga_raw_readl(struct socfpga_fpga_priv *priv,
> +				  u32 reg_offset)
> +{
> +	return __raw_readl(priv->fpga_base_addr + reg_offset);
> +}
> +
> +static void socfpga_fpga_raw_writel(struct socfpga_fpga_priv *priv,
> +				    u32 reg_offset, u32 value)
> +{
> +	__raw_writel(value, priv->fpga_base_addr + reg_offset);
> +}
> +
> +static void socfpga_fpga_data_writel(struct socfpga_fpga_priv *priv, u32 value)
> +{
> +	writel(value, priv->fpga_data_addr);
> +}
> +
> +static inline void socfpga_fpga_set_bitsl(struct socfpga_fpga_priv *priv,
> +					  u32 offset, u32 bits)
> +{
> +	u32 val;
> +
> +	val = socfpga_fpga_readl(priv, offset);
> +	val |= bits;
> +	socfpga_fpga_writel(priv, offset, val);
> +}
> +
> +static inline void socfpga_fpga_clr_bitsl(struct socfpga_fpga_priv *priv,
> +					  u32 offset, u32 bits)
> +{
> +	u32 val;
> +
> +	val = socfpga_fpga_readl(priv, offset);
> +	val &= ~bits;
> +	socfpga_fpga_writel(priv, offset, val);
> +}
> +
> +static u32 socfpga_fpga_mon_status_get(struct socfpga_fpga_priv *priv)
> +{
> +	return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST) &
> +		SOCFPGA_FPGMGR_MON_STATUS_MASK;
> +}
> +
> +static u32 socfpga_fpga_state_get(struct socfpga_fpga_priv *priv)
> +{
> +	u32 status = socfpga_fpga_mon_status_get(priv);
> +
> +	if ((status & SOCFPGA_FPGMGR_MON_FPGA_POWER_ON) == 0)
> +		return SOCFPGA_FPGMGR_STAT_POWER_OFF;
> +
> +	return socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST) &
> +		SOCFPGA_FPGMGR_STAT_STATE_MASK;
> +}
> +
> +static void socfpga_fpga_clear_done_status(struct socfpga_fpga_priv *priv)
> +{
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST,
> +			    SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE);
> +}
> +
> +/*
> + * Set the DCLKCNT, wait for DCLKSTAT to report the count completed, and clear
> + * the complete status.
> + */
> +static int socfpga_fpga_dclk_set_and_wait_clear(struct socfpga_fpga_priv *priv,
> +						u32 count)
> +{
> +	int timeout = 2;
> +	u32 done;
> +
> +	/* Clear any existing DONE status. */
> +	if (socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST))
> +		socfpga_fpga_clear_done_status(priv);
> +
> +	/* Issue the DCLK count. */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_DCLKCNT_OFST, count);
> +
> +	/* Poll DCLKSTAT to see if it completed in the timeout period. */
> +	do {
> +		done = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_DCLKSTAT_OFST);
> +		if (done == SOCFPGA_FPGMGR_DCLKSTAT_DCNTDONE_E_DONE) {
> +			socfpga_fpga_clear_done_status(priv);
> +			return 0;
> +		}
> +		udelay(1);
> +	} while (timeout--);
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static int socfpga_fpga_wait_for_state(struct socfpga_fpga_priv *priv,
> +				       u32 state)
> +{
> +	int timeout = 2;
> +
> +	/*
> +	 * HW doesn't support an interrupt for changes in state, so poll to see
> +	 * if it matches the requested state within the timeout period.
> +	 */
> +	do {
> +		if ((socfpga_fpga_state_get(priv) & state) != 0)
> +			return 0;
> +		msleep(20);
> +	} while (timeout--);
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static void socfpga_fpga_enable_irqs(struct socfpga_fpga_priv *priv, u32 irqs)
> +{
> +	/* set irqs to level sensitive */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTTYPE_LEVEL_OFST, 0);
> +
> +	/* set interrupt polarity */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INT_POL_OFST, irqs);
> +
> +	/* clear irqs */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
> +
> +	/* unmask interrupts */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTMSK_OFST, 0);
> +
> +	/* enable interrupts */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, irqs);
> +}
> +
> +static void socfpga_fpga_disable_irqs(struct socfpga_fpga_priv *priv)
> +{
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
> +}
> +
> +static irqreturn_t socfpga_fpga_isr(int irq, void *dev_id)
> +{
> +	struct socfpga_fpga_priv *priv = dev_id;
> +	u32 irqs, st;
> +	bool conf_done, nstatus;
> +
> +	/* clear irqs */
> +	irqs = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_INTSTAT_OFST);
> +
> +	socfpga_fpga_raw_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST, irqs);
> +
> +	st = socfpga_fpga_raw_readl(priv, SOCFPGA_FPGMGR_GPIO_EXT_PORTA_OFST);
> +	conf_done = (st & SOCFPGA_FPGMGR_MON_CONF_DONE) != 0;
> +	nstatus = (st & SOCFPGA_FPGMGR_MON_NSTATUS) != 0;
> +
> +	/* success */
> +	if (conf_done && nstatus) {
> +		/* disable irqs */
> +		socfpga_fpga_raw_writel(priv,
> +					SOCFPGA_FPGMGR_GPIO_INTEN_OFST, 0);
> +		complete(&priv->status_complete);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int socfpga_fpga_wait_for_config_done(struct socfpga_fpga_priv *priv)
> +{
> +	int timeout, ret = 0;
> +
> +	socfpga_fpga_disable_irqs(priv);
> +	init_completion(&priv->status_complete);
> +	socfpga_fpga_enable_irqs(priv, SOCFPGA_FPGMGR_MON_CONF_DONE);
> +
> +	timeout = wait_for_completion_interruptible_timeout(
> +						&priv->status_complete,
> +						msecs_to_jiffies(10));
> +	if (timeout == 0)
> +		ret = -ETIMEDOUT;
> +
> +	socfpga_fpga_disable_irqs(priv);
> +	return ret;
> +}
> +
> +static int socfpga_fpga_cfg_mode_get(struct socfpga_fpga_priv *priv)
> +{
> +	u32 msel;
> +
> +	msel = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_STAT_OFST);
> +	msel &= SOCFPGA_FPGMGR_STAT_MSEL_MASK;
> +	msel >>= SOCFPGA_FPGMGR_STAT_MSEL_SHIFT;
> +
> +	/* Check that this MSEL setting is supported */
> +	if ((msel >= ARRAY_SIZE(cfgmgr_modes)) || !cfgmgr_modes[msel].valid)
> +		return -EINVAL;
> +
> +	return msel;
> +}
> +
> +static int socfpga_fpga_cfg_mode_set(struct socfpga_fpga_priv *priv)
> +{
> +	u32 ctrl_reg;
> +	int mode;
> +
> +	/* get value from MSEL pins */
> +	mode = socfpga_fpga_cfg_mode_get(priv);
> +	if (mode < 0)
> +		return mode;
> +
> +	/* Adjust CTRL for the CDRATIO */
> +	ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
> +	ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CDRATIO_MASK;
> +	ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_CFGWDTH_MASK;
> +	ctrl_reg |= cfgmgr_modes[mode].ctrl;
> +
> +	/* Set NCE to 0. */
> +	ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCE;
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
> +
> +	return 0;
> +}
> +
> +static int socfpga_fpga_reset(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +	u32 ctrl_reg, status;
> +	int ret;
> +
> +	/*
> +	 * Step 1:
> +	 *  - Set CTRL.CFGWDTH, CTRL.CDRATIO to match cfg mode
> +	 *  - Set CTRL.NCE to 0
> +	 */
> +	ret = socfpga_fpga_cfg_mode_set(priv);
> +	if (ret)
> +		return ret;
> +
> +	/* Step 2: Set CTRL.EN to 1 */
> +	socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
> +			       SOCFPGA_FPGMGR_CTL_EN);
> +
> +	/* Step 3: Set CTRL.NCONFIGPULL to 1 to put FPGA in reset */
> +	ctrl_reg = socfpga_fpga_readl(priv, SOCFPGA_FPGMGR_CTL_OFST);
> +	ctrl_reg |= SOCFPGA_FPGMGR_CTL_NCFGPULL;
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
> +
> +	/* Step 4: Wait for STATUS.MODE to report FPGA is in reset phase */
> +	status = socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_RESET);
> +
> +	/* Step 5: Set CONTROL.NCONFIGPULL to 0 to release FPGA from reset */
> +	ctrl_reg &= ~SOCFPGA_FPGMGR_CTL_NCFGPULL;
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_CTL_OFST, ctrl_reg);
> +
> +	/* Timeout waiting for reset */
> +	if (status)
> +		return -ETIMEDOUT;
> +
> +	return 0;
> +}
> +
> +/*
> + * Prepare the FPGA to receive the configuration data.
> + */
> +static int socfpga_fpga_ops_configure_init(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +	int ret;
> +
> +	/* Steps 1 - 5: Reset the FPGA */
> +	ret = socfpga_fpga_reset(mgr);
> +	if (ret)
> +		return ret;
> +
> +	/* Step 6: Wait for FPGA to enter configuration phase */
> +	if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_CFG))
> +		return -ETIMEDOUT;
> +
> +	/* Step 7: Clear nSTATUS interrupt */
> +	socfpga_fpga_writel(priv, SOCFPGA_FPGMGR_GPIO_PORTA_EOI_OFST,
> +			    SOCFPGA_FPGMGR_MON_NSTATUS);
> +
> +	/* Step 8: Set CTRL.AXICFGEN to 1 to enable transfer of config data */
> +	socfpga_fpga_set_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
> +			       SOCFPGA_FPGMGR_CTL_AXICFGEN);
> +
> +	return 0;
> +}
> +
> +/*
> + * Step 9: write data to the FPGA data register
> + */
> +static int socfpga_fpga_ops_configure_write(struct fpga_manager *mgr,
> +					    const char *buf, size_t count)
> +{
> +	struct socfpga_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)) {
> +		socfpga_fpga_data_writel(priv, buffer_32[i++]);
> +		count -= sizeof(u32);
> +	}
> +
> +	/* Write out remaining non 32-bit chunks. */
> +	switch (count) {
> +	case 3:
> +		socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x00ffffff);
> +		break;
> +	case 2:
> +		socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x0000ffff);
> +		break;
> +	case 1:
> +		socfpga_fpga_data_writel(priv, buffer_32[i++] & 0x000000ff);
> +		break;
> +	default:
> +		/* This will never happen. */

why not just return any error code here even if this can't happen.


> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static int socfpga_fpga_ops_configure_complete(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +	u32 status;
> +
> +	/*
> +	 * Step 10:
> +	 *  - Observe CONF_DONE and nSTATUS (active low)
> +	 *  - if CONF_DONE = 1 and nSTATUS = 1, configuration was successful
> +	 *  - if CONF_DONE = 0 and nSTATUS = 0, configuration failed
> +	 */
> +	status = socfpga_fpga_wait_for_config_done(priv);
> +	if (status)
> +		return status;
> +
> +	/* Step 11: Clear CTRL.AXICFGEN to disable transfer of config data */
> +	socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
> +			       SOCFPGA_FPGMGR_CTL_AXICFGEN);
> +
> +	/*
> +	 * Step 12:
> +	 *  - Write 4 to DCLKCNT
> +	 *  - Wait for STATUS.DCNTDONE = 1
> +	 *  - Clear W1C bit in STATUS.DCNTDONE
> +	 */
> +	if (socfpga_fpga_dclk_set_and_wait_clear(priv, 4))
> +		return -ETIMEDOUT;
> +
> +	/* Step 13: Wait for STATUS.MODE to report USER MODE */
> +	if (socfpga_fpga_wait_for_state(priv, SOCFPGA_FPGMGR_STAT_USER_MODE))
> +		return -ETIMEDOUT;
> +
> +	/* Step 14: Set CTRL.EN to 0 */
> +	socfpga_fpga_clr_bitsl(priv, SOCFPGA_FPGMGR_CTL_OFST,
> +			       SOCFPGA_FPGMGR_CTL_EN);
> +
> +	return 0;
> +}
> +
> +/* Translate state register values to FPGA framework state */
> +static const enum fpga_mgr_states socfpga_state_to_framework_state[] = {
> +	[SOCFPGA_FPGMGR_STAT_POWER_OFF] = FPGA_MGR_STATE_POWER_OFF,
> +	[SOCFPGA_FPGMGR_STAT_RESET] = FPGA_MGR_STATE_RESET,
> +	[SOCFPGA_FPGMGR_STAT_CFG] = FPGA_MGR_STATE_WRITE_INIT,
> +	[SOCFPGA_FPGMGR_STAT_INIT] = FPGA_MGR_STATE_WRITE_INIT,
> +	[SOCFPGA_FPGMGR_STAT_USER_MODE] = FPGA_MGR_STATE_OPERATING,
> +	[SOCFPGA_FPGMGR_STAT_UNKNOWN] = FPGA_MGR_STATE_UNKNOWN,
> +};
> +
> +static enum fpga_mgr_states socfpga_fpga_ops_state(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +	enum fpga_mgr_states ret;
> +	u32 state;
> +
> +	state = socfpga_fpga_state_get(priv);
> +
> +	if (state < ARRAY_SIZE(socfpga_state_to_framework_state))
> +		ret = socfpga_state_to_framework_state[state];
> +	else
> +		ret = FPGA_MGR_STATE_UNKNOWN;
> +
> +	return ret;
> +}
> +
> +static int socfpga_fpga_regulators_on(struct socfpga_fpga_priv *priv)
> +{
> +	int i, ret;
> +
> +	for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
> +		ret = regulator_enable(priv->fpga_supplies[i]);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void socfpga_fpga_regulators_power_off(struct socfpga_fpga_priv *priv)
> +{
> +	int i;
> +
> +	for (i = SOCFPGA_FPGMGR_NUM_SUPPLIES - 1; i >= 0; i--)
> +		regulator_disable(priv->fpga_supplies[i]);
> +}
> +
> +static int socfpga_fpga_regulator_probe(struct platform_device *pdev,
> +					struct socfpga_fpga_priv *priv)
> +{
> +	struct regulator *supply;
> +	unsigned int i;
> +
> +	if (!IS_ENABLED(CONFIG_REGULATOR))
> +		return 0;
> +
> +	for (i = 0; i < SOCFPGA_FPGMGR_NUM_SUPPLIES; i++) {
> +		supply = devm_regulator_get_optional(&pdev->dev,
> +						     supply_names[i]);
> +		if (IS_ERR(supply)) {
> +			dev_err(&pdev->dev, "could not get regulators");
> +			return -EPROBE_DEFER;
> +		}
> +		priv->fpga_supplies[i] = supply;
> +	}
> +
> +	return socfpga_fpga_regulators_on(priv);
> +}
> +
> +static int socfpga_fpga_suspend(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +
> +	socfpga_fpga_regulators_power_off(priv);
> +
> +	return 0;
> +}
> +
> +static int socfpga_fpga_resume(struct fpga_manager *mgr)
> +{
> +	struct socfpga_fpga_priv *priv = mgr->priv;
> +	u32 state;
> +	unsigned int timeout;

add it to one line.

The rest is looks good to me. I think this is good to go in.

Acked-by: Michal Simek <michal.simek@xilinx.com>

Thanks,
Michal
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