[PATCH V8 0/8] misc: xilinx sd-fec drive

[PATCH V8 0/8] misc: xilinx sd-fec drive

[Dragan Cvetic]

This patchset is adding the full Soft Decision Forward Error
Correction (SD-FEC) driver implementation, driver DT binding and
driver documentation.

Forward Error Correction (FEC) codes such as Low Density Parity
Check (LDPC) and turbo codes provide a means to control errors in
data transmissions over unreliable or noisy communication
channels. The SD-FEC Integrated Block is an optimized block for
soft-decision decoding of these codes. Fixed turbo codes are
supported directly, whereas custom and standardized LDPC codes
are supported through the ability to specify the parity check
matrix through an AXI4-Lite bus or using the optional programmable
(PL)-based support logic. For the further information see
https://www.xilinx.com/support/documentation/ip_documentation/
sd_fec/v1_1/pg256-sdfec-integrated-block.pdf

This driver is a platform device driver which supports SDFEC16
(16nm) IP. SD-FEC driver supports LDPC decoding and encoding and
Turbo code decoding. LDPC codes can be specified on
a codeword-by-codeword basis, also a custom LDPC code can be used.

The SD-FEC driver exposes a char device interface and supports
file operations: open(), close(), poll() and ioctl(). The driver
allows only one usage of the device, open() limits the number of
driver instances. The driver also utilize Common Clock Framework
(CCF).

The control and monitoring is supported over ioctl system call.
The features supported by ioctl():
- enable or disable data pipes to/from device
- configure the FEC algorithm parameters
- set the order of data
- provide a control of a SDFEC bypass option
- activates/deactivates SD-FEC
- collect and provide statistical data
- enable/disable interrupt mode

Poll can be utilized to detect errors on IRQ trigger rather than
using looping status and stats ioctl's.

Tested-by: Santhosh Dyavanapally <SDYAVANA@xilinx.com>
Tested by: Punnaiah Choudary Kalluri <punnaia@xilinx.com>
Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>

Changes V1 -> V2:
- Removed unnecesary comenting from the commit messages.
- Removed error log messages which can be triggered from user space.
- Corrected the SDFEC table end addresses.
- Removed casting between user pointer and kernel pointer.
- Corrected definition of ioctl command code, used a corect type for
size parameters.
- Changes to declarations of IOCTL that pass structures, i.e. do not
use pointers for sizeof as prevents compile time checks
- IOCTL size fix, using a paging to manage a memory. Implemented a big
tables transfer from user to kernel with get_user_pages_fast().
- Removed unnecessary check after container_of.
- Removed not needed ioctl code checkes inside ioctl handler.
- Implemented compat_ioctl.
- Updated reviewer and tester lists.
- Updated documentation, added Limitation chapter related to fork()
and dup().

Link to V1 patch series:
https://lore.kernel.org/lkml/1552997064-432700-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V2 -> V3:
- Corrected a licence in xilinx_sdfec.h changed to uapi licence format.
- Corrected driver variable data types into user space data types.

Link to V2 patch series:
https://lore.kernel.org/lkml/1554804414-206099-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V3 -> V4:
- Migrate to simplier misc driver
- Fix DT example
- Remove helper function
- Remove unused open_count variable
- Remove some logs
- Change log level to dev_dbg in the most logs
- Change spin lock to spin_lock_irqsave/spin_lock_irqrestore
- Correct a licence date in xilinx_sdfec.c
- Add PTR_ERR in clock handling

Link to V3 patch series:
https://lore.kernel.org/lkml/1556402706-176271-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V4 -> V5:
- change atomic variables to c type variables
- align spinlock name to better description
- correct a logicla error in LDPC algorithm
- remove log messages
- remove useless if statements
- remove not needed fec_id variable
- squash commit 4 with 6

Link to V4 patch series:
https://lore.kernel.org/lkml/1558784245-108751-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V5 -> V6:
- the kernle/user space variables convert enums to __u32
- put device ID under IDR

Link to V5 patch series:
https://lore.kernel.org/lkml/1560038656-380620-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V6 -> V7:
- Fix maintainers list

Link to V6 patch series:
https://lore.kernel.org/lkml/1560174314-124649-1-git-send-email-dragan.cvetic@xilinx.com/

Changes V7 -> V8:
- 3 patches are added to char-misc, 8 to go
- remove holes in structs for 32bit and 64bit
- fix the compiler warning

Link to V7 patch series:
https://lore.kernel.org/lkml/1560274185-264438-1-git-send-email-dragan.cvetic@xilinx.com/

Dragan Cvetic (8):
  misc: xilinx_sdfec: Store driver config and state
  misc: xilinx_sdfec: Add ability to configure turbo
  misc: xilinx_sdfec: Add ability to configure LDPC
  misc: xilinx_sdfec: Add ability to get/set config
  misc: xilinx_sdfec: Support poll file operation
  misc: xilinx_sdfec: Add stats & status ioctls
  Docs: misc: xilinx_sdfec: Add documentation
  MAINTAINERS: add maintainer for SD-FEC

 Documentation/misc-devices/index.rst |    1 +
 MAINTAINERS                          |   11 +
 drivers/misc/xilinx_sdfec.c          | 1184 +++++++++++++++++++++++++++++++++-
 include/uapi/misc/xilinx_sdfec.h     |  448 +++++++++++++
 4 files changed, 1638 insertions(+), 6 deletions(-)
 create mode 100644 include/uapi/misc/xilinx_sdfec.h

-- 
2.7.4

[PATCH V8 1/8] misc: xilinx_sdfec: Store driver config and state

[Dragan Cvetic]

Stores configuration based on parameters from the DT
node and values from the SD-FEC core plus reads
the default state from the SD-FEC core. To obtain
values from the core register read, write capabilities
have been added plus related register map details.

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 305 ++++++++++++++++++++++++++++++++++++++-
 include/uapi/misc/xilinx_sdfec.h | 138 ++++++++++++++++++
 2 files changed, 437 insertions(+), 6 deletions(-)
 create mode 100644 include/uapi/misc/xilinx_sdfec.h

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index f257d38..24d9f79 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -20,11 +20,92 @@
 #include <linux/slab.h>
 #include <linux/clk.h>
 
+#include <uapi/misc/xilinx_sdfec.h>
+
 #define DEV_NAME_LEN 12
 
 static struct idr dev_idr;
 static struct mutex dev_idr_lock;
 
+/* Xilinx SDFEC Register Map */
+/* CODE_WRI_PROTECT Register */
+#define XSDFEC_CODE_WR_PROTECT_ADDR (0x4)
+
+/* ACTIVE Register */
+#define XSDFEC_ACTIVE_ADDR (0x8)
+#define XSDFEC_IS_ACTIVITY_SET (0x1)
+
+/* AXIS_WIDTH Register */
+#define XSDFEC_AXIS_WIDTH_ADDR (0xC)
+#define XSDFEC_AXIS_DOUT_WORDS_LSB (5)
+#define XSDFEC_AXIS_DOUT_WIDTH_LSB (3)
+#define XSDFEC_AXIS_DIN_WORDS_LSB (2)
+#define XSDFEC_AXIS_DIN_WIDTH_LSB (0)
+
+/* AXIS_ENABLE Register */
+#define XSDFEC_AXIS_ENABLE_ADDR (0x10)
+#define XSDFEC_AXIS_OUT_ENABLE_MASK (0x38)
+#define XSDFEC_AXIS_IN_ENABLE_MASK (0x7)
+#define XSDFEC_AXIS_ENABLE_MASK                                                \
+	(XSDFEC_AXIS_OUT_ENABLE_MASK | XSDFEC_AXIS_IN_ENABLE_MASK)
+
+/* FEC_CODE Register */
+#define XSDFEC_FEC_CODE_ADDR (0x14)
+
+/* ORDER Register Map */
+#define XSDFEC_ORDER_ADDR (0x18)
+
+/* Interrupt Status Register */
+#define XSDFEC_ISR_ADDR (0x1C)
+/* Interrupt Status Register Bit Mask */
+#define XSDFEC_ISR_MASK (0x3F)
+
+/* Write Only - Interrupt Enable Register */
+#define XSDFEC_IER_ADDR (0x20)
+/* Write Only - Interrupt Disable Register */
+#define XSDFEC_IDR_ADDR (0x24)
+/* Read Only - Interrupt Mask Register */
+#define XSDFEC_IMR_ADDR (0x28)
+
+/* ECC Interrupt Status Register */
+#define XSDFEC_ECC_ISR_ADDR (0x2C)
+/* Single Bit Errors */
+#define XSDFEC_ECC_ISR_SBE_MASK (0x7FF)
+/* PL Initialize Single Bit Errors */
+#define XSDFEC_PL_INIT_ECC_ISR_SBE_MASK (0x3C00000)
+/* Multi Bit Errors */
+#define XSDFEC_ECC_ISR_MBE_MASK (0x3FF800)
+/* PL Initialize Multi Bit Errors */
+#define XSDFEC_PL_INIT_ECC_ISR_MBE_MASK (0x3C000000)
+/* Multi Bit Error to Event Shift */
+#define XSDFEC_ECC_ISR_MBE_TO_EVENT_SHIFT (11)
+/* PL Initialize Multi Bit Error to Event Shift */
+#define XSDFEC_PL_INIT_ECC_ISR_MBE_TO_EVENT_SHIFT (4)
+/* ECC Interrupt Status Bit Mask */
+#define XSDFEC_ECC_ISR_MASK (XSDFEC_ECC_ISR_SBE_MASK | XSDFEC_ECC_ISR_MBE_MASK)
+/* ECC Interrupt Status PL Initialize Bit Mask */
+#define XSDFEC_PL_INIT_ECC_ISR_MASK                                            \
+	(XSDFEC_PL_INIT_ECC_ISR_SBE_MASK | XSDFEC_PL_INIT_ECC_ISR_MBE_MASK)
+/* ECC Interrupt Status All Bit Mask */
+#define XSDFEC_ALL_ECC_ISR_MASK                                                \
+	(XSDFEC_ECC_ISR_MASK | XSDFEC_PL_INIT_ECC_ISR_MASK)
+/* ECC Interrupt Status Single Bit Errors Mask */
+#define XSDFEC_ALL_ECC_ISR_SBE_MASK                                            \
+	(XSDFEC_ECC_ISR_SBE_MASK | XSDFEC_PL_INIT_ECC_ISR_SBE_MASK)
+/* ECC Interrupt Status Multi Bit Errors Mask */
+#define XSDFEC_ALL_ECC_ISR_MBE_MASK                                            \
+	(XSDFEC_ECC_ISR_MBE_MASK | XSDFEC_PL_INIT_ECC_ISR_MBE_MASK)
+
+/* Write Only - ECC Interrupt Enable Register */
+#define XSDFEC_ECC_IER_ADDR (0x30)
+/* Write Only - ECC Interrupt Disable Register */
+#define XSDFEC_ECC_IDR_ADDR (0x34)
+/* Read Only - ECC Interrupt Mask Register */
+#define XSDFEC_ECC_IMR_ADDR (0x38)
+
+/* BYPASS Register */
+#define XSDFEC_BYPASS_ADDR (0x3C)
+
 /**
  * struct xsdfec_clks - For managing SD-FEC clocks
  * @core_clk: Main processing clock for core
@@ -49,31 +130,237 @@ struct xsdfec_clks {
 
 /**
  * struct xsdfec_dev - Driver data for SDFEC
- * @regs: device physical base address
- * @dev: pointer to device struct
  * @miscdev: Misc device handle
- * @error_data_lock: Error counter and states spinlock
  * @clks: Clocks managed by the SDFEC driver
+ * @regs: device physical base address
+ * @dev: pointer to device struct
+ * @config: Configuration of the SDFEC device
  * @dev_name: Device name
+ * @state: State of the SDFEC device
+ * @error_data_lock: Error counter and states spinlock
  * @dev_id: Device ID
  *
  * This structure contains necessary state for SDFEC driver to operate
  */
 struct xsdfec_dev {
+	struct miscdevice miscdev;
+	struct xsdfec_clks clks;
 	void __iomem *regs;
 	struct device *dev;
-	struct miscdevice miscdev;
+	struct xsdfec_config config;
+	char dev_name[DEV_NAME_LEN];
+	enum xsdfec_state state;
 	/* Spinlock to protect state_updated and stats_updated */
 	spinlock_t error_data_lock;
-	struct xsdfec_clks clks;
-	char dev_name[DEV_NAME_LEN];
 	int dev_id;
 };
 
+static inline void xsdfec_regwrite(struct xsdfec_dev *xsdfec, u32 addr,
+				   u32 value)
+{
+	dev_dbg(xsdfec->dev, "Writing 0x%x to offset 0x%x", value, addr);
+	iowrite32(value, xsdfec->regs + addr);
+}
+
+static inline u32 xsdfec_regread(struct xsdfec_dev *xsdfec, u32 addr)
+{
+	u32 rval;
+
+	rval = ioread32(xsdfec->regs + addr);
+	dev_dbg(xsdfec->dev, "Read value = 0x%x from offset 0x%x", rval, addr);
+	return rval;
+}
+
+static void update_bool_config_from_reg(struct xsdfec_dev *xsdfec,
+					u32 reg_offset, u32 bit_num,
+					char *config_value)
+{
+	u32 reg_val;
+	u32 bit_mask = 1 << bit_num;
+
+	reg_val = xsdfec_regread(xsdfec, reg_offset);
+	*config_value = (reg_val & bit_mask) > 0;
+}
+
+static void update_config_from_hw(struct xsdfec_dev *xsdfec)
+{
+	u32 reg_value;
+	bool sdfec_started;
+
+	/* Update the Order */
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_ORDER_ADDR);
+	xsdfec->config.order = reg_value;
+
+	update_bool_config_from_reg(xsdfec, XSDFEC_BYPASS_ADDR,
+				    0, /* Bit Number, maybe change to mask */
+				    &xsdfec->config.bypass);
+
+	update_bool_config_from_reg(xsdfec, XSDFEC_CODE_WR_PROTECT_ADDR,
+				    0, /* Bit Number */
+				    &xsdfec->config.code_wr_protect);
+
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_IMR_ADDR);
+	xsdfec->config.irq.enable_isr = (reg_value & XSDFEC_ISR_MASK) > 0;
+
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_ECC_IMR_ADDR);
+	xsdfec->config.irq.enable_ecc_isr =
+		(reg_value & XSDFEC_ECC_ISR_MASK) > 0;
+
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_AXIS_ENABLE_ADDR);
+	sdfec_started = (reg_value & XSDFEC_AXIS_IN_ENABLE_MASK) > 0;
+	if (sdfec_started)
+		xsdfec->state = XSDFEC_STARTED;
+	else
+		xsdfec->state = XSDFEC_STOPPED;
+}
+
+static u32
+xsdfec_translate_axis_width_cfg_val(enum xsdfec_axis_width axis_width_cfg)
+{
+	u32 axis_width_field = 0;
+
+	switch (axis_width_cfg) {
+	case XSDFEC_1x128b:
+		axis_width_field = 0;
+		break;
+	case XSDFEC_2x128b:
+		axis_width_field = 1;
+		break;
+	case XSDFEC_4x128b:
+		axis_width_field = 2;
+		break;
+	}
+
+	return axis_width_field;
+}
+
+static u32 xsdfec_translate_axis_words_cfg_val(enum xsdfec_axis_word_include
+	axis_word_inc_cfg)
+{
+	u32 axis_words_field = 0;
+
+	if (axis_word_inc_cfg == XSDFEC_FIXED_VALUE ||
+	    axis_word_inc_cfg == XSDFEC_IN_BLOCK)
+		axis_words_field = 0;
+	else if (axis_word_inc_cfg == XSDFEC_PER_AXI_TRANSACTION)
+		axis_words_field = 1;
+
+	return axis_words_field;
+}
+
+static int xsdfec_cfg_axi_streams(struct xsdfec_dev *xsdfec)
+{
+	u32 reg_value;
+	u32 dout_words_field;
+	u32 dout_width_field;
+	u32 din_words_field;
+	u32 din_width_field;
+	struct xsdfec_config *config = &xsdfec->config;
+
+	/* translate config info to register values */
+	dout_words_field =
+		xsdfec_translate_axis_words_cfg_val(config->dout_word_include);
+	dout_width_field =
+		xsdfec_translate_axis_width_cfg_val(config->dout_width);
+	din_words_field =
+		xsdfec_translate_axis_words_cfg_val(config->din_word_include);
+	din_width_field =
+		xsdfec_translate_axis_width_cfg_val(config->din_width);
+
+	reg_value = dout_words_field << XSDFEC_AXIS_DOUT_WORDS_LSB;
+	reg_value |= dout_width_field << XSDFEC_AXIS_DOUT_WIDTH_LSB;
+	reg_value |= din_words_field << XSDFEC_AXIS_DIN_WORDS_LSB;
+	reg_value |= din_width_field << XSDFEC_AXIS_DIN_WIDTH_LSB;
+
+	xsdfec_regwrite(xsdfec, XSDFEC_AXIS_WIDTH_ADDR, reg_value);
+
+	return 0;
+}
+
 static const struct file_operations xsdfec_fops = {
 	.owner = THIS_MODULE,
 };
 
+static int xsdfec_parse_of(struct xsdfec_dev *xsdfec)
+{
+	struct device *dev = xsdfec->dev;
+	struct device_node *node = dev->of_node;
+	int rval;
+	const char *fec_code;
+	u32 din_width;
+	u32 din_word_include;
+	u32 dout_width;
+	u32 dout_word_include;
+
+	rval = of_property_read_string(node, "xlnx,sdfec-code", &fec_code);
+	if (rval < 0)
+		return rval;
+
+	if (!strcasecmp(fec_code, "ldpc"))
+		xsdfec->config.code = XSDFEC_LDPC_CODE;
+	else if (!strcasecmp(fec_code, "turbo"))
+		xsdfec->config.code = XSDFEC_TURBO_CODE;
+	else
+		return -EINVAL;
+
+	rval = of_property_read_u32(node, "xlnx,sdfec-din-words",
+				    &din_word_include);
+	if (rval < 0)
+		return rval;
+
+	if (din_word_include < XSDFEC_AXIS_WORDS_INCLUDE_MAX)
+		xsdfec->config.din_word_include = din_word_include;
+	else
+		return -EINVAL;
+
+	rval = of_property_read_u32(node, "xlnx,sdfec-din-width", &din_width);
+	if (rval < 0)
+		return rval;
+
+	switch (din_width) {
+	/* Fall through and set for valid values */
+	case XSDFEC_1x128b:
+	case XSDFEC_2x128b:
+	case XSDFEC_4x128b:
+		xsdfec->config.din_width = din_width;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	rval = of_property_read_u32(node, "xlnx,sdfec-dout-words",
+				    &dout_word_include);
+	if (rval < 0)
+		return rval;
+
+	if (dout_word_include < XSDFEC_AXIS_WORDS_INCLUDE_MAX)
+		xsdfec->config.dout_word_include = dout_word_include;
+	else
+		return -EINVAL;
+
+	rval = of_property_read_u32(node, "xlnx,sdfec-dout-width", &dout_width);
+	if (rval < 0)
+		return rval;
+
+	switch (dout_width) {
+	/* Fall through and set for valid values */
+	case XSDFEC_1x128b:
+	case XSDFEC_2x128b:
+	case XSDFEC_4x128b:
+		xsdfec->config.dout_width = dout_width;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Write LDPC to CODE Register */
+	xsdfec_regwrite(xsdfec, XSDFEC_FEC_CODE_ADDR, xsdfec->config.code);
+
+	xsdfec_cfg_axi_streams(xsdfec);
+
+	return 0;
+}
+
 static int xsdfec_clk_init(struct platform_device *pdev,
 			   struct xsdfec_clks *clks)
 {
@@ -260,6 +547,12 @@ static int xsdfec_probe(struct platform_device *pdev)
 		goto err_xsdfec_dev;
 	}
 
+	err = xsdfec_parse_of(xsdfec);
+	if (err < 0)
+		goto err_xsdfec_dev;
+
+	update_config_from_hw(xsdfec);
+
 	/* Save driver private data */
 	platform_set_drvdata(pdev, xsdfec);
 
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
new file mode 100644
index 0000000..330ea25
--- /dev/null
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -0,0 +1,138 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Xilinx SD-FEC
+ *
+ * Copyright (C) 2019 Xilinx, Inc.
+ *
+ * Description:
+ * This driver is developed for SDFEC16 IP. It provides a char device
+ * in sysfs and supports file operations like open(), close() and ioctl().
+ */
+#ifndef __XILINX_SDFEC_H__
+#define __XILINX_SDFEC_H__
+
+#include <linux/types.h>
+
+/**
+ * enum xsdfec_code - Code Type.
+ * @XSDFEC_TURBO_CODE: Driver is configured for Turbo mode.
+ * @XSDFEC_LDPC_CODE: Driver is configured for LDPC mode.
+ *
+ * This enum is used to indicate the mode of the driver. The mode is determined
+ * by checking which codes are set in the driver. Note that the mode cannot be
+ * changed by the driver.
+ */
+enum xsdfec_code {
+	XSDFEC_TURBO_CODE = 0,
+	XSDFEC_LDPC_CODE,
+};
+
+/**
+ * enum xsdfec_order - Order
+ * @XSDFEC_MAINTAIN_ORDER: Maintain order execution of blocks.
+ * @XSDFEC_OUT_OF_ORDER: Out-of-order execution of blocks.
+ *
+ * This enum is used to indicate whether the order of blocks can change from
+ * input to output.
+ */
+enum xsdfec_order {
+	XSDFEC_MAINTAIN_ORDER = 0,
+	XSDFEC_OUT_OF_ORDER,
+};
+
+/**
+ * enum xsdfec_state - State.
+ * @XSDFEC_INIT: Driver is initialized.
+ * @XSDFEC_STARTED: Driver is started.
+ * @XSDFEC_STOPPED: Driver is stopped.
+ * @XSDFEC_NEEDS_RESET: Driver needs to be reset.
+ * @XSDFEC_PL_RECONFIGURE: Programmable Logic needs to be recofigured.
+ *
+ * This enum is used to indicate the state of the driver.
+ */
+enum xsdfec_state {
+	XSDFEC_INIT = 0,
+	XSDFEC_STARTED,
+	XSDFEC_STOPPED,
+	XSDFEC_NEEDS_RESET,
+	XSDFEC_PL_RECONFIGURE,
+};
+
+/**
+ * enum xsdfec_axis_width - AXIS_WIDTH.DIN Setting for 128-bit width.
+ * @XSDFEC_1x128b: DIN data input stream consists of a 128-bit lane
+ * @XSDFEC_2x128b: DIN data input stream consists of two 128-bit lanes
+ * @XSDFEC_4x128b: DIN data input stream consists of four 128-bit lanes
+ *
+ * This enum is used to indicate the AXIS_WIDTH.DIN setting for 128-bit width.
+ * The number of lanes of the DIN data input stream depends upon the
+ * AXIS_WIDTH.DIN parameter.
+ */
+enum xsdfec_axis_width {
+	XSDFEC_1x128b = 1,
+	XSDFEC_2x128b = 2,
+	XSDFEC_4x128b = 4,
+};
+
+/**
+ * enum xsdfec_axis_word_include - Words Configuration.
+ * @XSDFEC_FIXED_VALUE: Fixed, the DIN_WORDS AXI4-Stream interface is removed
+ *			from the IP instance and is driven with the specified
+ *			number of words.
+ * @XSDFEC_IN_BLOCK: In Block, configures the IP instance to expect a single
+ *		     DIN_WORDS value per input code block. The DIN_WORDS
+ *		     interface is present.
+ * @XSDFEC_PER_AXI_TRANSACTION: Per Transaction, configures the IP instance to
+ * expect one DIN_WORDS value per input transaction on the DIN interface. The
+ * DIN_WORDS interface is present.
+ * @XSDFEC_AXIS_WORDS_INCLUDE_MAX: Used to indicate out of bound Words
+ *				   Configurations.
+ *
+ * This enum is used to specify the DIN_WORDS configuration.
+ */
+enum xsdfec_axis_word_include {
+	XSDFEC_FIXED_VALUE = 0,
+	XSDFEC_IN_BLOCK,
+	XSDFEC_PER_AXI_TRANSACTION,
+	XSDFEC_AXIS_WORDS_INCLUDE_MAX,
+};
+
+/**
+ * struct xsdfec_irq - Enabling or Disabling Interrupts.
+ * @enable_isr: If true enables the ISR
+ * @enable_ecc_isr: If true enables the ECC ISR
+ */
+struct xsdfec_irq {
+	__s8 enable_isr;
+	__s8 enable_ecc_isr;
+};
+
+/**
+ * struct xsdfec_config - Configuration of SD-FEC core.
+ * @code: The codes being used by the SD-FEC instance
+ * @order: Order of Operation
+ * @din_width: Width of the DIN AXI4-Stream
+ * @din_word_include: How DIN_WORDS are inputted
+ * @dout_width: Width of the DOUT AXI4-Stream
+ * @dout_word_include: HOW DOUT_WORDS are outputted
+ * @irq: Enabling or disabling interrupts
+ * @bypass: Is the core being bypassed
+ * @code_wr_protect: Is write protection of LDPC codes enabled
+ */
+struct xsdfec_config {
+	__u32 code;
+	__u32 order;
+	__u32 din_width;
+	__u32 din_word_include;
+	__u32 dout_width;
+	__u32 dout_word_include;
+	struct xsdfec_irq irq;
+	__s8 bypass;
+	__s8 code_wr_protect;
+};
+
+/*
+ * XSDFEC IOCTL List
+ */
+#define XSDFEC_MAGIC 'f'
+#endif /* __XILINX_SDFEC_H__ */
-- 
2.7.4

[PATCH V8 2/8] misc: xilinx_sdfec: Add ability to configure turbo

[Dragan Cvetic]

Add the capability to configure and retrieve turbo mode
via the ioctls XSDFEC_SET_TURBO and XSDFEC_GET_TURBO.
Add char device interface per DT node present and support
file operations:
- open(),
- close(),
- unlocked_ioctl(),
- compat_ioctl().

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 110 +++++++++++++++++++++++++++++++++++++++
 include/uapi/misc/xilinx_sdfec.h |  67 ++++++++++++++++++++++++
 2 files changed, 177 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 24d9f79..d3dba7e 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -19,6 +19,7 @@
 #include <linux/poll.h>
 #include <linux/slab.h>
 #include <linux/clk.h>
+#include <linux/compat.h>
 
 #include <uapi/misc/xilinx_sdfec.h>
 
@@ -106,6 +107,12 @@ static struct mutex dev_idr_lock;
 /* BYPASS Register */
 #define XSDFEC_BYPASS_ADDR (0x3C)
 
+/* Turbo Code Register */
+#define XSDFEC_TURBO_ADDR (0x100)
+#define XSDFEC_TURBO_SCALE_MASK (0xFFF)
+#define XSDFEC_TURBO_SCALE_BIT_POS (8)
+#define XSDFEC_TURBO_SCALE_MAX (15)
+
 /**
  * struct xsdfec_clks - For managing SD-FEC clocks
  * @core_clk: Main processing clock for core
@@ -214,6 +221,55 @@ static void update_config_from_hw(struct xsdfec_dev *xsdfec)
 		xsdfec->state = XSDFEC_STOPPED;
 }
 
+static int xsdfec_set_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	struct xsdfec_turbo turbo;
+	int err;
+	u32 turbo_write;
+
+	err = copy_from_user(&turbo, arg, sizeof(turbo));
+	if (err)
+		return -EFAULT;
+
+	if (turbo.alg >= XSDFEC_TURBO_ALG_MAX)
+		return -EINVAL;
+
+	if (turbo.scale > XSDFEC_TURBO_SCALE_MAX)
+		return -EINVAL;
+
+	/* Check to see what device tree says about the FEC codes */
+	if (xsdfec->config.code == XSDFEC_LDPC_CODE)
+		return -EIO;
+
+	turbo_write = ((turbo.scale & XSDFEC_TURBO_SCALE_MASK)
+		       << XSDFEC_TURBO_SCALE_BIT_POS) |
+		      turbo.alg;
+	xsdfec_regwrite(xsdfec, XSDFEC_TURBO_ADDR, turbo_write);
+	return err;
+}
+
+static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	u32 reg_value;
+	struct xsdfec_turbo turbo_params;
+	int err;
+
+	if (xsdfec->config.code == XSDFEC_LDPC_CODE)
+		return -EIO;
+
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_TURBO_ADDR);
+
+	turbo_params.scale = (reg_value & XSDFEC_TURBO_SCALE_MASK) >>
+			     XSDFEC_TURBO_SCALE_BIT_POS;
+	turbo_params.alg = reg_value & 0x1;
+
+	err = copy_to_user(arg, &turbo_params, sizeof(turbo_params));
+	if (err)
+		err = -EFAULT;
+
+	return err;
+}
+
 static u32
 xsdfec_translate_axis_width_cfg_val(enum xsdfec_axis_width axis_width_cfg)
 {
@@ -277,8 +333,62 @@ static int xsdfec_cfg_axi_streams(struct xsdfec_dev *xsdfec)
 	return 0;
 }
 
+static int xsdfec_dev_open(struct inode *iptr, struct file *fptr)
+{
+	return 0;
+}
+
+static int xsdfec_dev_release(struct inode *iptr, struct file *fptr)
+{
+	return 0;
+}
+
+static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
+			     unsigned long data)
+{
+	struct xsdfec_dev *xsdfec;
+	void __user *arg = NULL;
+	int rval = -EINVAL;
+
+	xsdfec = container_of(fptr->private_data, struct xsdfec_dev, miscdev);
+
+	/* check if ioctl argument is present and valid */
+	if (_IOC_DIR(cmd) != _IOC_NONE) {
+		arg = (void __user *)data;
+		if (!arg)
+			return rval;
+	}
+
+	switch (cmd) {
+	case XSDFEC_SET_TURBO:
+		rval = xsdfec_set_turbo(xsdfec, arg);
+		break;
+	case XSDFEC_GET_TURBO:
+		rval = xsdfec_get_turbo(xsdfec, arg);
+		break;
+	default:
+		/* Should not get here */
+		break;
+	}
+	return rval;
+}
+
+#ifdef CONFIG_COMPAT
+static long xsdfec_dev_compat_ioctl(struct file *file, unsigned int cmd,
+				    unsigned long data)
+{
+	return xsdfec_dev_ioctl(file, cmd, (unsigned long)compat_ptr(data));
+}
+#endif
+
 static const struct file_operations xsdfec_fops = {
 	.owner = THIS_MODULE,
+	.open = xsdfec_dev_open,
+	.release = xsdfec_dev_release,
+	.unlocked_ioctl = xsdfec_dev_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = xsdfec_dev_compat_ioctl,
+#endif
 };
 
 static int xsdfec_parse_of(struct xsdfec_dev *xsdfec)
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index 330ea25..34f32c3 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -41,6 +41,22 @@ enum xsdfec_order {
 };
 
 /**
+ * enum xsdfec_turbo_alg - Turbo Algorithm Type.
+ * @XSDFEC_MAX_SCALE: Max Log-Map algorithm with extrinsic scaling. When
+ *		      scaling is set to this is equivalent to the Max Log-Map
+ *		      algorithm.
+ * @XSDFEC_MAX_STAR: Log-Map algorithm.
+ * @XSDFEC_TURBO_ALG_MAX: Used to indicate out of bound Turbo algorithms.
+ *
+ * This enum specifies which Turbo Decode algorithm is in use.
+ */
+enum xsdfec_turbo_alg {
+	XSDFEC_MAX_SCALE = 0,
+	XSDFEC_MAX_STAR,
+	XSDFEC_TURBO_ALG_MAX,
+};
+
+/**
  * enum xsdfec_state - State.
  * @XSDFEC_INIT: Driver is initialized.
  * @XSDFEC_STARTED: Driver is started.
@@ -98,6 +114,29 @@ enum xsdfec_axis_word_include {
 };
 
 /**
+ * struct xsdfec_turbo - User data for Turbo codes.
+ * @alg: Specifies which Turbo decode algorithm to use
+ * @scale: Specifies the extrinsic scaling to apply when the Max Scale algorithm
+ *	   has been selected
+ *
+ * Turbo code structure to communicate parameters to XSDFEC driver.
+ */
+struct xsdfec_turbo {
+	__u32 alg;
+	__u8 scale;
+};
+
+/**
+ * struct xsdfec_status - Status of SD-FEC core.
+ * @state: State of the SD-FEC core
+ * @activity: Describes if the SD-FEC instance is Active
+ */
+struct xsdfec_status {
+	__u32 state;
+	__s8 activity;
+};
+
+/**
  * struct xsdfec_irq - Enabling or Disabling Interrupts.
  * @enable_isr: If true enables the ISR
  * @enable_ecc_isr: If true enables the ECC ISR
@@ -135,4 +174,32 @@ struct xsdfec_config {
  * XSDFEC IOCTL List
  */
 #define XSDFEC_MAGIC 'f'
+/**
+ * DOC: XSDFEC_SET_TURBO
+ * @Parameters
+ *
+ * @struct xsdfec_turbo *
+ *	Pointer to the &struct xsdfec_turbo that contains the Turbo decode
+ *	settings for the SD-FEC core
+ *
+ * @Description
+ *
+ * ioctl that sets the SD-FEC Turbo parameter values
+ *
+ * This can only be used when the driver is in the XSDFEC_STOPPED state
+ */
+#define XSDFEC_SET_TURBO _IOW(XSDFEC_MAGIC, 4, struct xsdfec_turbo)
+/**
+ * DOC: XSDFEC_GET_TURBO
+ * @Parameters
+ *
+ * @struct xsdfec_turbo *
+ *	Pointer to the &struct xsdfec_turbo that contains the current Turbo
+ *	decode settings of the SD-FEC Block
+ *
+ * @Description
+ *
+ * ioctl that returns SD-FEC turbo param values
+ */
+#define XSDFEC_GET_TURBO _IOR(XSDFEC_MAGIC, 7, struct xsdfec_turbo)
 #endif /* __XILINX_SDFEC_H__ */
-- 
2.7.4

[PATCH V8 3/8] misc: xilinx_sdfec: Add ability to configure LDPC

[Dragan Cvetic]

Add the capability to configure LDPC mode via the ioctl
XSDFEC_ADD_LDPC_CODE_PARAMS.

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 324 +++++++++++++++++++++++++++++++++++++++
 include/uapi/misc/xilinx_sdfec.h |  98 ++++++++++++
 2 files changed, 422 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index d3dba7e..9be4de0 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -20,6 +20,7 @@
 #include <linux/slab.h>
 #include <linux/clk.h>
 #include <linux/compat.h>
+#include <linux/highmem.h>
 
 #include <uapi/misc/xilinx_sdfec.h>
 
@@ -113,6 +114,57 @@ static struct mutex dev_idr_lock;
 #define XSDFEC_TURBO_SCALE_BIT_POS (8)
 #define XSDFEC_TURBO_SCALE_MAX (15)
 
+/* REG0 Register */
+#define XSDFEC_LDPC_CODE_REG0_ADDR_BASE (0x2000)
+#define XSDFEC_LDPC_CODE_REG0_ADDR_HIGH (0x27F0)
+#define XSDFEC_REG0_N_MIN (4)
+#define XSDFEC_REG0_N_MAX (32768)
+#define XSDFEC_REG0_N_MUL_P (256)
+#define XSDFEC_REG0_N_LSB (0)
+#define XSDFEC_REG0_K_MIN (2)
+#define XSDFEC_REG0_K_MAX (32766)
+#define XSDFEC_REG0_K_MUL_P (256)
+#define XSDFEC_REG0_K_LSB (16)
+
+/* REG1 Register */
+#define XSDFEC_LDPC_CODE_REG1_ADDR_BASE (0x2004)
+#define XSDFEC_LDPC_CODE_REG1_ADDR_HIGH (0x27f4)
+#define XSDFEC_REG1_PSIZE_MIN (2)
+#define XSDFEC_REG1_PSIZE_MAX (512)
+#define XSDFEC_REG1_NO_PACKING_MASK (0x400)
+#define XSDFEC_REG1_NO_PACKING_LSB (10)
+#define XSDFEC_REG1_NM_MASK (0xFF800)
+#define XSDFEC_REG1_NM_LSB (11)
+#define XSDFEC_REG1_BYPASS_MASK (0x100000)
+
+/* REG2 Register */
+#define XSDFEC_LDPC_CODE_REG2_ADDR_BASE (0x2008)
+#define XSDFEC_LDPC_CODE_REG2_ADDR_HIGH (0x27f8)
+#define XSDFEC_REG2_NLAYERS_MIN (1)
+#define XSDFEC_REG2_NLAYERS_MAX (256)
+#define XSDFEC_REG2_NNMQC_MASK (0xFFE00)
+#define XSDFEC_REG2_NMQC_LSB (9)
+#define XSDFEC_REG2_NORM_TYPE_MASK (0x100000)
+#define XSDFEC_REG2_NORM_TYPE_LSB (20)
+#define XSDFEC_REG2_SPECIAL_QC_MASK (0x200000)
+#define XSDFEC_REG2_SPEICAL_QC_LSB (21)
+#define XSDFEC_REG2_NO_FINAL_PARITY_MASK (0x400000)
+#define XSDFEC_REG2_NO_FINAL_PARITY_LSB (22)
+#define XSDFEC_REG2_MAX_SCHEDULE_MASK (0x1800000)
+#define XSDFEC_REG2_MAX_SCHEDULE_LSB (23)
+
+/* REG3 Register */
+#define XSDFEC_LDPC_CODE_REG3_ADDR_BASE (0x200C)
+#define XSDFEC_LDPC_CODE_REG3_ADDR_HIGH (0x27FC)
+#define XSDFEC_REG3_LA_OFF_LSB (8)
+#define XSDFEC_REG3_QC_OFF_LSB (16)
+
+#define XSDFEC_LDPC_REG_JUMP (0x10)
+#define XSDFEC_REG_WIDTH_JUMP (4)
+
+/* The maximum number of pinned pages */
+#define MAX_NUM_PAGES ((XSDFEC_QC_TABLE_DEPTH / PAGE_SIZE) + 1)
+
 /**
  * struct xsdfec_clks - For managing SD-FEC clocks
  * @core_clk: Main processing clock for core
@@ -270,6 +322,275 @@ static int xsdfec_get_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
 	return err;
 }
 
+static int xsdfec_reg0_write(struct xsdfec_dev *xsdfec, u32 n, u32 k, u32 psize,
+			     u32 offset)
+{
+	u32 wdata;
+
+	if (n < XSDFEC_REG0_N_MIN || n > XSDFEC_REG0_N_MAX ||
+	    (n > XSDFEC_REG0_N_MUL_P * psize) || n <= k || ((n % psize) != 0)) {
+		dev_dbg(xsdfec->dev, "N value is not in range");
+		return -EINVAL;
+	}
+	n <<= XSDFEC_REG0_N_LSB;
+
+	if (k < XSDFEC_REG0_K_MIN || k > XSDFEC_REG0_K_MAX ||
+	    (k > XSDFEC_REG0_K_MUL_P * psize) || ((k % psize) != 0)) {
+		dev_dbg(xsdfec->dev, "K value is not in range");
+		return -EINVAL;
+	}
+	k = k << XSDFEC_REG0_K_LSB;
+	wdata = k | n;
+
+	if (XSDFEC_LDPC_CODE_REG0_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+	    XSDFEC_LDPC_CODE_REG0_ADDR_HIGH) {
+		dev_dbg(xsdfec->dev, "Writing outside of LDPC reg0 space 0x%x",
+			XSDFEC_LDPC_CODE_REG0_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP));
+		return -EINVAL;
+	}
+	xsdfec_regwrite(xsdfec,
+			XSDFEC_LDPC_CODE_REG0_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP),
+			wdata);
+	return 0;
+}
+
+static int xsdfec_reg1_write(struct xsdfec_dev *xsdfec, u32 psize,
+			     u32 no_packing, u32 nm, u32 offset)
+{
+	u32 wdata;
+
+	if (psize < XSDFEC_REG1_PSIZE_MIN || psize > XSDFEC_REG1_PSIZE_MAX) {
+		dev_dbg(xsdfec->dev, "Psize is not in range");
+		return -EINVAL;
+	}
+
+	if (no_packing != 0 && no_packing != 1)
+		dev_dbg(xsdfec->dev, "No-packing bit register invalid");
+	no_packing = ((no_packing << XSDFEC_REG1_NO_PACKING_LSB) &
+		      XSDFEC_REG1_NO_PACKING_MASK);
+
+	if (nm & ~(XSDFEC_REG1_NM_MASK >> XSDFEC_REG1_NM_LSB))
+		dev_dbg(xsdfec->dev, "NM is beyond 10 bits");
+	nm = (nm << XSDFEC_REG1_NM_LSB) & XSDFEC_REG1_NM_MASK;
+
+	wdata = nm | no_packing | psize;
+	if (XSDFEC_LDPC_CODE_REG1_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+	    XSDFEC_LDPC_CODE_REG1_ADDR_HIGH) {
+		dev_dbg(xsdfec->dev, "Writing outside of LDPC reg1 space 0x%x",
+			XSDFEC_LDPC_CODE_REG1_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP));
+		return -EINVAL;
+	}
+	xsdfec_regwrite(xsdfec,
+			XSDFEC_LDPC_CODE_REG1_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP),
+			wdata);
+	return 0;
+}
+
+static int xsdfec_reg2_write(struct xsdfec_dev *xsdfec, u32 nlayers, u32 nmqc,
+			     u32 norm_type, u32 special_qc, u32 no_final_parity,
+			     u32 max_schedule, u32 offset)
+{
+	u32 wdata;
+
+	if (nlayers < XSDFEC_REG2_NLAYERS_MIN ||
+	    nlayers > XSDFEC_REG2_NLAYERS_MAX) {
+		dev_dbg(xsdfec->dev, "Nlayers is not in range");
+		return -EINVAL;
+	}
+
+	if (nmqc & ~(XSDFEC_REG2_NNMQC_MASK >> XSDFEC_REG2_NMQC_LSB))
+		dev_dbg(xsdfec->dev, "NMQC exceeds 11 bits");
+	nmqc = (nmqc << XSDFEC_REG2_NMQC_LSB) & XSDFEC_REG2_NNMQC_MASK;
+
+	if (norm_type > 1)
+		dev_dbg(xsdfec->dev, "Norm type is invalid");
+	norm_type = ((norm_type << XSDFEC_REG2_NORM_TYPE_LSB) &
+		     XSDFEC_REG2_NORM_TYPE_MASK);
+	if (special_qc > 1)
+		dev_dbg(xsdfec->dev, "Special QC in invalid");
+	special_qc = ((special_qc << XSDFEC_REG2_SPEICAL_QC_LSB) &
+		      XSDFEC_REG2_SPECIAL_QC_MASK);
+
+	if (no_final_parity > 1)
+		dev_dbg(xsdfec->dev, "No final parity check invalid");
+	no_final_parity =
+		((no_final_parity << XSDFEC_REG2_NO_FINAL_PARITY_LSB) &
+		 XSDFEC_REG2_NO_FINAL_PARITY_MASK);
+	if (max_schedule &
+	    ~(XSDFEC_REG2_MAX_SCHEDULE_MASK >> XSDFEC_REG2_MAX_SCHEDULE_LSB))
+		dev_dbg(xsdfec->dev, "Max Schdule exceeds 2 bits");
+	max_schedule = ((max_schedule << XSDFEC_REG2_MAX_SCHEDULE_LSB) &
+			XSDFEC_REG2_MAX_SCHEDULE_MASK);
+
+	wdata = (max_schedule | no_final_parity | special_qc | norm_type |
+		 nmqc | nlayers);
+
+	if (XSDFEC_LDPC_CODE_REG2_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+	    XSDFEC_LDPC_CODE_REG2_ADDR_HIGH) {
+		dev_dbg(xsdfec->dev, "Writing outside of LDPC reg2 space 0x%x",
+			XSDFEC_LDPC_CODE_REG2_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP));
+		return -EINVAL;
+	}
+	xsdfec_regwrite(xsdfec,
+			XSDFEC_LDPC_CODE_REG2_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP),
+			wdata);
+	return 0;
+}
+
+static int xsdfec_reg3_write(struct xsdfec_dev *xsdfec, u8 sc_off, u8 la_off,
+			     u16 qc_off, u32 offset)
+{
+	u32 wdata;
+
+	wdata = ((qc_off << XSDFEC_REG3_QC_OFF_LSB) |
+		 (la_off << XSDFEC_REG3_LA_OFF_LSB) | sc_off);
+	if (XSDFEC_LDPC_CODE_REG3_ADDR_BASE + (offset * XSDFEC_LDPC_REG_JUMP) >
+	    XSDFEC_LDPC_CODE_REG3_ADDR_HIGH) {
+		dev_dbg(xsdfec->dev, "Writing outside of LDPC reg3 space 0x%x",
+			XSDFEC_LDPC_CODE_REG3_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP));
+		return -EINVAL;
+	}
+	xsdfec_regwrite(xsdfec,
+			XSDFEC_LDPC_CODE_REG3_ADDR_BASE +
+				(offset * XSDFEC_LDPC_REG_JUMP),
+			wdata);
+	return 0;
+}
+
+static int xsdfec_table_write(struct xsdfec_dev *xsdfec, u32 offset,
+			      u32 *src_ptr, u32 len, const u32 base_addr,
+			      const u32 depth)
+{
+	u32 reg = 0;
+	u32 res;
+	u32 n, i;
+	u32 *addr = NULL;
+	struct page *page[MAX_NUM_PAGES];
+
+	/*
+	 * Writes that go beyond the length of
+	 * Shared Scale(SC) table should fail
+	 */
+	if ((XSDFEC_REG_WIDTH_JUMP * (offset + len)) > depth) {
+		dev_dbg(xsdfec->dev, "Write exceeds SC table length");
+		return -EINVAL;
+	}
+
+	n = (len * XSDFEC_REG_WIDTH_JUMP) / PAGE_SIZE;
+	if ((len * XSDFEC_REG_WIDTH_JUMP) % PAGE_SIZE)
+		n += 1;
+
+	res = get_user_pages_fast((unsigned long)src_ptr, n, 0, page);
+	if (res < n) {
+		for (i = 0; i < res; i++)
+			put_page(page[i]);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < n; i++) {
+		addr = kmap(page[i]);
+		do {
+			xsdfec_regwrite(xsdfec,
+					base_addr + ((offset + reg) *
+						     XSDFEC_REG_WIDTH_JUMP),
+					addr[reg]);
+			reg++;
+		} while ((reg < len) &&
+			 ((reg * XSDFEC_REG_WIDTH_JUMP) % PAGE_SIZE));
+		put_page(page[i]);
+	}
+	return reg;
+}
+
+static int xsdfec_add_ldpc(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	struct xsdfec_ldpc_params *ldpc;
+	int ret, n;
+
+	ldpc = kzalloc(sizeof(*ldpc), GFP_KERNEL);
+	if (!ldpc)
+		return -ENOMEM;
+
+	ret = copy_from_user(ldpc, arg, sizeof(*ldpc));
+	if (ret)
+		goto err_out;
+
+	if (xsdfec->config.code == XSDFEC_TURBO_CODE) {
+		ret = -EIO;
+		goto err_out;
+	}
+
+	/* Verify Device has not started */
+	if (xsdfec->state == XSDFEC_STARTED) {
+		ret = -EIO;
+		goto err_out;
+	}
+
+	if (xsdfec->config.code_wr_protect) {
+		ret = -EIO;
+		goto err_out;
+	}
+
+	/* Write Reg 0 */
+	ret = xsdfec_reg0_write(xsdfec, ldpc->n, ldpc->k, ldpc->psize,
+				ldpc->code_id);
+	if (ret)
+		goto err_out;
+
+	/* Write Reg 1 */
+	ret = xsdfec_reg1_write(xsdfec, ldpc->psize, ldpc->no_packing, ldpc->nm,
+				ldpc->code_id);
+	if (ret)
+		goto err_out;
+
+	/* Write Reg 2 */
+	ret = xsdfec_reg2_write(xsdfec, ldpc->nlayers, ldpc->nmqc,
+				ldpc->norm_type, ldpc->special_qc,
+				ldpc->no_final_parity, ldpc->max_schedule,
+				ldpc->code_id);
+	if (ret)
+		goto err_out;
+
+	/* Write Reg 3 */
+	ret = xsdfec_reg3_write(xsdfec, ldpc->sc_off, ldpc->la_off,
+				ldpc->qc_off, ldpc->code_id);
+	if (ret)
+		goto err_out;
+
+	/* Write Shared Codes */
+	n = ldpc->nlayers / 4;
+	if (ldpc->nlayers % 4)
+		n++;
+
+	ret = xsdfec_table_write(xsdfec, ldpc->sc_off, ldpc->sc_table, n,
+				 XSDFEC_LDPC_SC_TABLE_ADDR_BASE,
+				 XSDFEC_SC_TABLE_DEPTH);
+	if (ret < 0)
+		goto err_out;
+
+	ret = xsdfec_table_write(xsdfec, 4 * ldpc->la_off, ldpc->la_table,
+				 ldpc->nlayers, XSDFEC_LDPC_LA_TABLE_ADDR_BASE,
+				 XSDFEC_LA_TABLE_DEPTH);
+	if (ret < 0)
+		goto err_out;
+
+	ret = xsdfec_table_write(xsdfec, 4 * ldpc->qc_off, ldpc->qc_table,
+				 ldpc->nqc, XSDFEC_LDPC_QC_TABLE_ADDR_BASE,
+				 XSDFEC_QC_TABLE_DEPTH);
+	if (ret > 0)
+		ret = 0;
+err_out:
+	kfree(ldpc);
+	return ret;
+}
+
 static u32
 xsdfec_translate_axis_width_cfg_val(enum xsdfec_axis_width axis_width_cfg)
 {
@@ -366,6 +687,9 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 	case XSDFEC_GET_TURBO:
 		rval = xsdfec_get_turbo(xsdfec, arg);
 		break;
+	case XSDFEC_ADD_LDPC_CODE_PARAMS:
+		rval = xsdfec_add_ldpc(xsdfec, arg);
+		break;
 	default:
 		/* Should not get here */
 		break;
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index 34f32c3..ce532a5 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -13,6 +13,22 @@
 
 #include <linux/types.h>
 
+/* Shared LDPC Tables */
+#define XSDFEC_LDPC_SC_TABLE_ADDR_BASE (0x10000)
+#define XSDFEC_LDPC_SC_TABLE_ADDR_HIGH (0x10400)
+#define XSDFEC_LDPC_LA_TABLE_ADDR_BASE (0x18000)
+#define XSDFEC_LDPC_LA_TABLE_ADDR_HIGH (0x19000)
+#define XSDFEC_LDPC_QC_TABLE_ADDR_BASE (0x20000)
+#define XSDFEC_LDPC_QC_TABLE_ADDR_HIGH (0x28000)
+
+/* LDPC tables depth */
+#define XSDFEC_SC_TABLE_DEPTH                                                  \
+	(XSDFEC_LDPC_SC_TABLE_ADDR_HIGH - XSDFEC_LDPC_SC_TABLE_ADDR_BASE)
+#define XSDFEC_LA_TABLE_DEPTH                                                  \
+	(XSDFEC_LDPC_LA_TABLE_ADDR_HIGH - XSDFEC_LDPC_LA_TABLE_ADDR_BASE)
+#define XSDFEC_QC_TABLE_DEPTH                                                  \
+	(XSDFEC_LDPC_QC_TABLE_ADDR_HIGH - XSDFEC_LDPC_QC_TABLE_ADDR_BASE)
+
 /**
  * enum xsdfec_code - Code Type.
  * @XSDFEC_TURBO_CODE: Driver is configured for Turbo mode.
@@ -127,6 +143,53 @@ struct xsdfec_turbo {
 };
 
 /**
+ * struct xsdfec_ldpc_params - User data for LDPC codes.
+ * @n: Number of code word bits
+ * @k: Number of information bits
+ * @psize: Size of sub-matrix
+ * @nlayers: Number of layers in code
+ * @nqc: Quasi Cyclic Number
+ * @nmqc: Number of M-sized QC operations in parity check matrix
+ * @nm: Number of M-size vectors in N
+ * @norm_type: Normalization required or not
+ * @no_packing: Determines if multiple QC ops should be performed
+ * @special_qc: Sub-Matrix property for Circulant weight > 0
+ * @no_final_parity: Decide if final parity check needs to be performed
+ * @max_schedule: Experimental code word scheduling limit
+ * @sc_off: SC offset
+ * @la_off: LA offset
+ * @qc_off: QC offset
+ * @sc_table: Pointer to SC Table which must be page aligned
+ * @la_table: Pointer to LA Table which must be page aligned
+ * @qc_table: Pointer to QC Table which must be page aligned
+ * @code_id: LDPC Code
+ *
+ * This structure describes the LDPC code that is passed to the driver by the
+ * application.
+ */
+struct xsdfec_ldpc_params {
+	__u32 n;
+	__u32 k;
+	__u32 psize;
+	__u32 nlayers;
+	__u32 nqc;
+	__u32 nmqc;
+	__u32 nm;
+	__u32 norm_type;
+	__u32 no_packing;
+	__u32 special_qc;
+	__u32 no_final_parity;
+	__u32 max_schedule;
+	__u32 sc_off;
+	__u32 la_off;
+	__u32 qc_off;
+	__u32 *sc_table;
+	__u32 *la_table;
+	__u32 *qc_table;
+	__u16 code_id;
+};
+
+/**
  * struct xsdfec_status - Status of SD-FEC core.
  * @state: State of the SD-FEC core
  * @activity: Describes if the SD-FEC instance is Active
@@ -170,6 +233,20 @@ struct xsdfec_config {
 	__s8 code_wr_protect;
 };
 
+/**
+ * struct xsdfec_ldpc_param_table_sizes - Used to store sizes of SD-FEC table
+ *					  entries for an individual LPDC code
+ *					  parameter.
+ * @sc_size: Size of SC table used
+ * @la_size: Size of LA table used
+ * @qc_size: Size of QC table used
+ */
+struct xsdfec_ldpc_param_table_sizes {
+	__u32 sc_size;
+	__u32 la_size;
+	__u32 qc_size;
+};
+
 /*
  * XSDFEC IOCTL List
  */
@@ -190,6 +267,27 @@ struct xsdfec_config {
  */
 #define XSDFEC_SET_TURBO _IOW(XSDFEC_MAGIC, 4, struct xsdfec_turbo)
 /**
+ * DOC: XSDFEC_ADD_LDPC_CODE_PARAMS
+ * @Parameters
+ *
+ * @struct xsdfec_ldpc_params *
+ *	Pointer to the &struct xsdfec_ldpc_params that contains the LDPC code
+ *	parameters to be added to the SD-FEC Block
+ *
+ * @Description
+ * ioctl to add an LDPC code to the SD-FEC LDPC codes
+ *
+ * This can only be used when:
+ *
+ * - Driver is in the XSDFEC_STOPPED state
+ *
+ * - SD-FEC core is configured as LPDC
+ *
+ * - SD-FEC Code Write Protection is disabled
+ */
+#define XSDFEC_ADD_LDPC_CODE_PARAMS                                            \
+	_IOW(XSDFEC_MAGIC, 5, struct xsdfec_ldpc_params)
+/**
  * DOC: XSDFEC_GET_TURBO
  * @Parameters
  *
-- 
2.7.4

[PATCH V8 4/8] misc: xilinx_sdfec: Add ability to get/set config

[Dragan Cvetic]

- Add capability to get SD-FEC config data using ioctl
XSDFEC_GET_CONFIG.

- Add capability to set SD-FEC data order using ioctl
SDFEC_SET_ORDER.

- Add capability to set SD-FEC bypass option using ioctl
XSDFEC_SET_BYPASS.

- Add capability to set SD-FEC active state using ioctl
XSDFEC_IS_ACTIVE.

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 88 ++++++++++++++++++++++++++++++++++++++++
 include/uapi/misc/xilinx_sdfec.h | 57 ++++++++++++++++++++++++++
 2 files changed, 145 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 9be4de0..579f236 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -273,6 +273,17 @@ static void update_config_from_hw(struct xsdfec_dev *xsdfec)
 		xsdfec->state = XSDFEC_STOPPED;
 }
 
+static int xsdfec_get_config(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	int err;
+
+	err = copy_to_user(arg, &xsdfec->config, sizeof(xsdfec->config));
+	if (err)
+		err = -EFAULT;
+
+	return err;
+}
+
 static int xsdfec_set_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
 {
 	struct xsdfec_turbo turbo;
@@ -591,6 +602,71 @@ static int xsdfec_add_ldpc(struct xsdfec_dev *xsdfec, void __user *arg)
 	return ret;
 }
 
+static int xsdfec_set_order(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	bool order_invalid;
+	enum xsdfec_order order;
+	int err;
+
+	err = get_user(order, (enum xsdfec_order *)arg);
+	if (err)
+		return -EFAULT;
+
+	order_invalid = (order != XSDFEC_MAINTAIN_ORDER) &&
+			(order != XSDFEC_OUT_OF_ORDER);
+	if (order_invalid)
+		return -EINVAL;
+
+	/* Verify Device has not started */
+	if (xsdfec->state == XSDFEC_STARTED)
+		return -EIO;
+
+	xsdfec_regwrite(xsdfec, XSDFEC_ORDER_ADDR, order);
+
+	xsdfec->config.order = order;
+
+	return 0;
+}
+
+static int xsdfec_set_bypass(struct xsdfec_dev *xsdfec, bool __user *arg)
+{
+	bool bypass;
+	int err;
+
+	err = get_user(bypass, arg);
+	if (err)
+		return -EFAULT;
+
+	/* Verify Device has not started */
+	if (xsdfec->state == XSDFEC_STARTED)
+		return -EIO;
+
+	if (bypass)
+		xsdfec_regwrite(xsdfec, XSDFEC_BYPASS_ADDR, 1);
+	else
+		xsdfec_regwrite(xsdfec, XSDFEC_BYPASS_ADDR, 0);
+
+	xsdfec->config.bypass = bypass;
+
+	return 0;
+}
+
+static int xsdfec_is_active(struct xsdfec_dev *xsdfec, bool __user *arg)
+{
+	u32 reg_value;
+	bool is_active;
+	int err;
+
+	reg_value = xsdfec_regread(xsdfec, XSDFEC_ACTIVE_ADDR);
+	/* using a double ! operator instead of casting */
+	is_active = !!(reg_value & XSDFEC_IS_ACTIVITY_SET);
+	err = put_user(is_active, arg);
+	if (err)
+		return -EFAULT;
+
+	return err;
+}
+
 static u32
 xsdfec_translate_axis_width_cfg_val(enum xsdfec_axis_width axis_width_cfg)
 {
@@ -681,6 +757,9 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 	}
 
 	switch (cmd) {
+	case XSDFEC_GET_CONFIG:
+		rval = xsdfec_get_config(xsdfec, arg);
+		break;
 	case XSDFEC_SET_TURBO:
 		rval = xsdfec_set_turbo(xsdfec, arg);
 		break;
@@ -690,6 +769,15 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 	case XSDFEC_ADD_LDPC_CODE_PARAMS:
 		rval = xsdfec_add_ldpc(xsdfec, arg);
 		break;
+	case XSDFEC_SET_ORDER:
+		rval = xsdfec_set_order(xsdfec, arg);
+		break;
+	case XSDFEC_SET_BYPASS:
+		rval = xsdfec_set_bypass(xsdfec, arg);
+		break;
+	case XSDFEC_IS_ACTIVE:
+		rval = xsdfec_is_active(xsdfec, (bool __user *)arg);
+		break;
 	default:
 		/* Should not get here */
 		break;
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index ce532a5..b8897ce 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -288,6 +288,19 @@ struct xsdfec_ldpc_param_table_sizes {
 #define XSDFEC_ADD_LDPC_CODE_PARAMS                                            \
 	_IOW(XSDFEC_MAGIC, 5, struct xsdfec_ldpc_params)
 /**
+ * DOC: XSDFEC_GET_CONFIG
+ * @Parameters
+ *
+ * @struct xsdfec_config *
+ *	Pointer to the &struct xsdfec_config that contains the current
+ *	configuration settings of the SD-FEC Block
+ *
+ * @Description
+ *
+ * ioctl that returns SD-FEC core configuration
+ */
+#define XSDFEC_GET_CONFIG _IOR(XSDFEC_MAGIC, 6, struct xsdfec_config)
+/**
  * DOC: XSDFEC_GET_TURBO
  * @Parameters
  *
@@ -300,4 +313,48 @@ struct xsdfec_ldpc_param_table_sizes {
  * ioctl that returns SD-FEC turbo param values
  */
 #define XSDFEC_GET_TURBO _IOR(XSDFEC_MAGIC, 7, struct xsdfec_turbo)
+/**
+ * DOC: XSDFEC_SET_ORDER
+ * @Parameters
+ *
+ * @struct unsigned long *
+ *	Pointer to the unsigned long that contains a value from the
+ *	@enum xsdfec_order
+ *
+ * @Description
+ *
+ * ioctl that sets order, if order of blocks can change from input to output
+ *
+ * This can only be used when the driver is in the XSDFEC_STOPPED state
+ */
+#define XSDFEC_SET_ORDER _IOW(XSDFEC_MAGIC, 8, unsigned long)
+/**
+ * DOC: XSDFEC_SET_BYPASS
+ * @Parameters
+ *
+ * @struct bool *
+ *	Pointer to bool that sets the bypass value, where false results in
+ *	normal operation and false results in the SD-FEC performing the
+ *	configured operations (same number of cycles) but output data matches
+ *	the input data
+ *
+ * @Description
+ *
+ * ioctl that sets bypass.
+ *
+ * This can only be used when the driver is in the XSDFEC_STOPPED state
+ */
+#define XSDFEC_SET_BYPASS _IOW(XSDFEC_MAGIC, 9, bool)
+/**
+ * DOC: XSDFEC_IS_ACTIVE
+ * @Parameters
+ *
+ * @struct bool *
+ *	Pointer to bool that returns true if the SD-FEC is processing data
+ *
+ * @Description
+ *
+ * ioctl that determines if SD-FEC is processing data
+ */
+#define XSDFEC_IS_ACTIVE _IOR(XSDFEC_MAGIC, 10, bool)
 #endif /* __XILINX_SDFEC_H__ */
-- 
2.7.4

[PATCH V8 5/8] misc: xilinx_sdfec: Support poll file operation

[Dragan Cvetic]

Support monitoring and detecting the SD-FEC error events
through IRQ and poll file operation.

The SD-FEC device can detect one-error or multi-error events.
An error triggers an interrupt which creates and run the ONE_SHOT
IRQ thread.
The ONE_SHOT IRQ thread detects type of error and pass that
information to the poll function.
The file_operation callback poll(), collects the events and
updates the statistics accordingly.
The function poll blocks() on waiting queue which can be
unblocked by ONE_SHOT IRQ handling thread.

Support SD-FEC interrupt set ioctl callback.
The SD-FEC can detect two type of errors: coding errors (ECC) and
a data interface errors (TLAST).
The errors are  events which can trigger an IRQ if enabled.
The driver can monitor and detect these errors through IRQ.
Also the driver updates the statistical data.

Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 240 ++++++++++++++++++++++++++++++++++++++-
 include/uapi/misc/xilinx_sdfec.h |  13 +++
 2 files changed, 249 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 579f236..61775c5 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -191,27 +191,43 @@ struct xsdfec_clks {
  * struct xsdfec_dev - Driver data for SDFEC
  * @miscdev: Misc device handle
  * @clks: Clocks managed by the SDFEC driver
- * @regs: device physical base address
- * @dev: pointer to device struct
+ * @waitq: Driver wait queue
  * @config: Configuration of the SDFEC device
  * @dev_name: Device name
+ * @flags: spinlock flags
+ * @regs: device physical base address
+ * @dev: pointer to device struct
  * @state: State of the SDFEC device
  * @error_data_lock: Error counter and states spinlock
  * @dev_id: Device ID
+ * @isr_err_count: Count of ISR errors
+ * @cecc_count: Count of Correctable ECC errors (SBE)
+ * @uecc_count: Count of Uncorrectable ECC errors (MBE)
+ * @irq: IRQ number
+ * @state_updated: indicates State updated by interrupt handler
+ * @stats_updated: indicates Stats updated by interrupt handler
  *
  * This structure contains necessary state for SDFEC driver to operate
  */
 struct xsdfec_dev {
 	struct miscdevice miscdev;
 	struct xsdfec_clks clks;
-	void __iomem *regs;
-	struct device *dev;
+	wait_queue_head_t waitq;
 	struct xsdfec_config config;
 	char dev_name[DEV_NAME_LEN];
+	unsigned long flags;
+	void __iomem *regs;
+	struct device *dev;
 	enum xsdfec_state state;
 	/* Spinlock to protect state_updated and stats_updated */
 	spinlock_t error_data_lock;
 	int dev_id;
+	u32 isr_err_count;
+	u32 cecc_count;
+	u32 uecc_count;
+	int irq;
+	bool state_updated;
+	bool stats_updated;
 };
 
 static inline void xsdfec_regwrite(struct xsdfec_dev *xsdfec, u32 addr,
@@ -284,6 +300,90 @@ static int xsdfec_get_config(struct xsdfec_dev *xsdfec, void __user *arg)
 	return err;
 }
 
+static int xsdfec_isr_enable(struct xsdfec_dev *xsdfec, bool enable)
+{
+	u32 mask_read;
+
+	if (enable) {
+		/* Enable */
+		xsdfec_regwrite(xsdfec, XSDFEC_IER_ADDR, XSDFEC_ISR_MASK);
+		mask_read = xsdfec_regread(xsdfec, XSDFEC_IMR_ADDR);
+		if (mask_read & XSDFEC_ISR_MASK) {
+			dev_dbg(xsdfec->dev,
+				"SDFEC enabling irq with IER failed");
+			return -EIO;
+		}
+	} else {
+		/* Disable */
+		xsdfec_regwrite(xsdfec, XSDFEC_IDR_ADDR, XSDFEC_ISR_MASK);
+		mask_read = xsdfec_regread(xsdfec, XSDFEC_IMR_ADDR);
+		if ((mask_read & XSDFEC_ISR_MASK) != XSDFEC_ISR_MASK) {
+			dev_dbg(xsdfec->dev,
+				"SDFEC disabling irq with IDR failed");
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+static int xsdfec_ecc_isr_enable(struct xsdfec_dev *xsdfec, bool enable)
+{
+	u32 mask_read;
+
+	if (enable) {
+		/* Enable */
+		xsdfec_regwrite(xsdfec, XSDFEC_ECC_IER_ADDR,
+				XSDFEC_ALL_ECC_ISR_MASK);
+		mask_read = xsdfec_regread(xsdfec, XSDFEC_ECC_IMR_ADDR);
+		if (mask_read & XSDFEC_ALL_ECC_ISR_MASK) {
+			dev_dbg(xsdfec->dev,
+				"SDFEC enabling ECC irq with ECC IER failed");
+			return -EIO;
+		}
+	} else {
+		/* Disable */
+		xsdfec_regwrite(xsdfec, XSDFEC_ECC_IDR_ADDR,
+				XSDFEC_ALL_ECC_ISR_MASK);
+		mask_read = xsdfec_regread(xsdfec, XSDFEC_ECC_IMR_ADDR);
+		if (!(((mask_read & XSDFEC_ALL_ECC_ISR_MASK) ==
+		       XSDFEC_ECC_ISR_MASK) ||
+		      ((mask_read & XSDFEC_ALL_ECC_ISR_MASK) ==
+		       XSDFEC_PL_INIT_ECC_ISR_MASK))) {
+			dev_dbg(xsdfec->dev,
+				"SDFEC disable ECC irq with ECC IDR failed");
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
+static int xsdfec_set_irq(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	struct xsdfec_irq irq;
+	int err;
+	int isr_err;
+	int ecc_err;
+
+	err = copy_from_user(&irq, arg, sizeof(irq));
+	if (err)
+		return -EFAULT;
+
+	/* Setup tlast related IRQ */
+	isr_err = xsdfec_isr_enable(xsdfec, irq.enable_isr);
+	if (!isr_err)
+		xsdfec->config.irq.enable_isr = irq.enable_isr;
+
+	/* Setup ECC related IRQ */
+	ecc_err = xsdfec_ecc_isr_enable(xsdfec, irq.enable_ecc_isr);
+	if (!ecc_err)
+		xsdfec->config.irq.enable_ecc_isr = irq.enable_ecc_isr;
+
+	if (isr_err < 0 || ecc_err < 0)
+		err = -EIO;
+
+	return err;
+}
+
 static int xsdfec_set_turbo(struct xsdfec_dev *xsdfec, void __user *arg)
 {
 	struct xsdfec_turbo turbo;
@@ -760,6 +860,9 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 	case XSDFEC_GET_CONFIG:
 		rval = xsdfec_get_config(xsdfec, arg);
 		break;
+	case XSDFEC_SET_IRQ:
+		rval = xsdfec_set_irq(xsdfec, arg);
+		break;
 	case XSDFEC_SET_TURBO:
 		rval = xsdfec_set_turbo(xsdfec, arg);
 		break;
@@ -793,11 +896,36 @@ static long xsdfec_dev_compat_ioctl(struct file *file, unsigned int cmd,
 }
 #endif
 
+static unsigned int xsdfec_poll(struct file *file, poll_table *wait)
+{
+	unsigned int mask = 0;
+	struct xsdfec_dev *xsdfec;
+
+	xsdfec = container_of(file->private_data, struct xsdfec_dev, miscdev);
+
+	if (!xsdfec)
+		return POLLNVAL | POLLHUP;
+
+	poll_wait(file, &xsdfec->waitq, wait);
+
+	/* XSDFEC ISR detected an error */
+	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
+	if (xsdfec->state_updated)
+		mask |= POLLIN | POLLPRI;
+
+	if (xsdfec->stats_updated)
+		mask |= POLLIN | POLLRDNORM;
+	spin_unlock_irqrestore(&xsdfec->error_data_lock, xsdfec->flags);
+
+	return mask;
+}
+
 static const struct file_operations xsdfec_fops = {
 	.owner = THIS_MODULE,
 	.open = xsdfec_dev_open,
 	.release = xsdfec_dev_release,
 	.unlocked_ioctl = xsdfec_dev_ioctl,
+	.poll = xsdfec_poll,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl = xsdfec_dev_compat_ioctl,
 #endif
@@ -883,6 +1011,91 @@ static int xsdfec_parse_of(struct xsdfec_dev *xsdfec)
 	return 0;
 }
 
+static irqreturn_t xsdfec_irq_thread(int irq, void *dev_id)
+{
+	struct xsdfec_dev *xsdfec = dev_id;
+	irqreturn_t ret = IRQ_HANDLED;
+	u32 ecc_err;
+	u32 isr_err;
+	u32 uecc_count;
+	u32 cecc_count;
+	u32 isr_err_count;
+	u32 aecc_count;
+	u32 tmp;
+
+	WARN_ON(xsdfec->irq != irq);
+
+	/* Mask Interrupts */
+	xsdfec_isr_enable(xsdfec, false);
+	xsdfec_ecc_isr_enable(xsdfec, false);
+	/* Read ISR */
+	ecc_err = xsdfec_regread(xsdfec, XSDFEC_ECC_ISR_ADDR);
+	isr_err = xsdfec_regread(xsdfec, XSDFEC_ISR_ADDR);
+	/* Clear the interrupts */
+	xsdfec_regwrite(xsdfec, XSDFEC_ECC_ISR_ADDR, ecc_err);
+	xsdfec_regwrite(xsdfec, XSDFEC_ISR_ADDR, isr_err);
+
+	tmp = ecc_err & XSDFEC_ALL_ECC_ISR_MBE_MASK;
+	/* Count uncorrectable 2-bit errors */
+	uecc_count = hweight32(tmp);
+	/* Count all ECC errors */
+	aecc_count = hweight32(ecc_err);
+	/* Number of correctable 1-bit ECC error */
+	cecc_count = aecc_count - 2 * uecc_count;
+	/* Count ISR errors */
+	isr_err_count = hweight32(isr_err);
+	dev_dbg(xsdfec->dev, "tmp=%x, uecc=%x, aecc=%x, cecc=%x, isr=%x", tmp,
+		uecc_count, aecc_count, cecc_count, isr_err_count);
+	dev_dbg(xsdfec->dev, "uecc=%x, cecc=%x, isr=%x", xsdfec->uecc_count,
+		xsdfec->cecc_count, xsdfec->isr_err_count);
+
+	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
+	/* Add new errors to a 2-bits counter */
+	if (uecc_count)
+		xsdfec->uecc_count += uecc_count;
+	/* Add new errors to a 1-bits counter */
+	if (cecc_count)
+		xsdfec->cecc_count += cecc_count;
+	/* Add new errors to a ISR counter */
+	if (isr_err_count)
+		xsdfec->isr_err_count += isr_err_count;
+
+	/* Update state/stats flag */
+	if (uecc_count) {
+		if (ecc_err & XSDFEC_ECC_ISR_MBE_MASK)
+			xsdfec->state = XSDFEC_NEEDS_RESET;
+		else if (ecc_err & XSDFEC_PL_INIT_ECC_ISR_MBE_MASK)
+			xsdfec->state = XSDFEC_PL_RECONFIGURE;
+		xsdfec->stats_updated = true;
+		xsdfec->state_updated = true;
+	}
+
+	if (cecc_count)
+		xsdfec->stats_updated = true;
+
+	if (isr_err_count) {
+		xsdfec->state = XSDFEC_NEEDS_RESET;
+		xsdfec->stats_updated = true;
+		xsdfec->state_updated = true;
+	}
+
+	spin_unlock_irqrestore(&xsdfec->error_data_lock, xsdfec->flags);
+	dev_dbg(xsdfec->dev, "state=%x, stats=%x", xsdfec->state_updated,
+		xsdfec->stats_updated);
+
+	/* Enable another polling */
+	if (xsdfec->state_updated || xsdfec->stats_updated)
+		wake_up_interruptible(&xsdfec->waitq);
+	else
+		ret = IRQ_NONE;
+
+	/* Unmask Interrupts */
+	xsdfec_isr_enable(xsdfec, true);
+	xsdfec_ecc_isr_enable(xsdfec, true);
+
+	return ret;
+}
+
 static int xsdfec_clk_init(struct platform_device *pdev,
 			   struct xsdfec_clks *clks)
 {
@@ -1049,6 +1262,7 @@ static int xsdfec_probe(struct platform_device *pdev)
 	struct device *dev;
 	struct resource *res;
 	int err;
+	bool irq_enabled = true;
 
 	xsdfec = devm_kzalloc(&pdev->dev, sizeof(*xsdfec), GFP_KERNEL);
 	if (!xsdfec)
@@ -1069,6 +1283,12 @@ static int xsdfec_probe(struct platform_device *pdev)
 		goto err_xsdfec_dev;
 	}
 
+	xsdfec->irq = platform_get_irq(pdev, 0);
+	if (xsdfec->irq < 0) {
+		dev_dbg(dev, "platform_get_irq failed");
+		irq_enabled = false;
+	}
+
 	err = xsdfec_parse_of(xsdfec);
 	if (err < 0)
 		goto err_xsdfec_dev;
@@ -1078,6 +1298,18 @@ static int xsdfec_probe(struct platform_device *pdev)
 	/* Save driver private data */
 	platform_set_drvdata(pdev, xsdfec);
 
+	if (irq_enabled) {
+		init_waitqueue_head(&xsdfec->waitq);
+		/* Register IRQ thread */
+		err = devm_request_threaded_irq(dev, xsdfec->irq, NULL,
+						xsdfec_irq_thread, IRQF_ONESHOT,
+						"xilinx-sdfec16", xsdfec);
+		if (err < 0) {
+			dev_err(dev, "unable to request IRQ%d", xsdfec->irq);
+			goto err_xsdfec_dev;
+		}
+	}
+
 	mutex_lock(&dev_idr_lock);
 	err = idr_alloc(&dev_idr, xsdfec->dev_name, 0, 0, GFP_KERNEL);
 	mutex_unlock(&dev_idr_lock);
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index b8897ce..85ee288 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -252,6 +252,19 @@ struct xsdfec_ldpc_param_table_sizes {
  */
 #define XSDFEC_MAGIC 'f'
 /**
+ * DOC: XSDFEC_SET_IRQ
+ * @Parameters
+ *
+ * @struct xsdfec_irq *
+ *	Pointer to the &struct xsdfec_irq that contains the interrupt settings
+ *	for the SD-FEC core
+ *
+ * @Description
+ *
+ * ioctl to enable or disable irq
+ */
+#define XSDFEC_SET_IRQ _IOW(XSDFEC_MAGIC, 3, struct xsdfec_irq)
+/**
  * DOC: XSDFEC_SET_TURBO
  * @Parameters
  *
-- 
2.7.4

[PATCH V8 6/8] misc: xilinx_sdfec: Add stats & status ioctls

[Dragan Cvetic]

SD-FEC statistic data are:
- count of data interface errors (isr_err_count)
- count of Correctable ECC errors (cecc_count)
- count of Uncorrectable ECC errors (uecc_count)

Add support:
1. clear stats ioctl callback which clears collected
statistic data,
2. get stats ioctl callback which reads a collected
statistic data,
3. set default configuration ioctl callback,
4. start ioctl callback enables SD-FEC HW,
5. stop ioctl callback disables SD-FEC HW.

In a failed state driver enables the following ioctls:
- get status
- get statistics
- clear stats
- set default SD-FEC device configuration

Tested-by: Santhosh Dyavanapally <SDYAVANA@xilinx.com>
Tested by: Punnaiah Choudary Kalluri <punnaia@xilinx.com>
Tested-by: Derek Kiernan <derek.kiernan@xilinx.com>
Tested-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 drivers/misc/xilinx_sdfec.c      | 125 +++++++++++++++++++++++++++++++++++++++
 include/uapi/misc/xilinx_sdfec.h |  75 +++++++++++++++++++++++
 2 files changed, 200 insertions(+)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 61775c5..45f127a 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -206,6 +206,7 @@ struct xsdfec_clks {
  * @irq: IRQ number
  * @state_updated: indicates State updated by interrupt handler
  * @stats_updated: indicates Stats updated by interrupt handler
+ * @intr_enabled: indicates IRQ enabled
  *
  * This structure contains necessary state for SDFEC driver to operate
  */
@@ -228,6 +229,7 @@ struct xsdfec_dev {
 	int irq;
 	bool state_updated;
 	bool stats_updated;
+	bool intr_enabled;
 };
 
 static inline void xsdfec_regwrite(struct xsdfec_dev *xsdfec, u32 addr,
@@ -289,6 +291,25 @@ static void update_config_from_hw(struct xsdfec_dev *xsdfec)
 		xsdfec->state = XSDFEC_STOPPED;
 }
 
+static int xsdfec_get_status(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	struct xsdfec_status status;
+	int err;
+
+	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
+	status.state = xsdfec->state;
+	xsdfec->state_updated = false;
+	spin_unlock_irqrestore(&xsdfec->error_data_lock, xsdfec->flags);
+	status.activity = (xsdfec_regread(xsdfec, XSDFEC_ACTIVE_ADDR) &
+			   XSDFEC_IS_ACTIVITY_SET);
+
+	err = copy_to_user(arg, &status, sizeof(status));
+	if (err)
+		err = -EFAULT;
+
+	return err;
+}
+
 static int xsdfec_get_config(struct xsdfec_dev *xsdfec, void __user *arg)
 {
 	int err;
@@ -840,6 +861,82 @@ static int xsdfec_dev_release(struct inode *iptr, struct file *fptr)
 	return 0;
 }
 
+static int xsdfec_start(struct xsdfec_dev *xsdfec)
+{
+	u32 regread;
+
+	regread = xsdfec_regread(xsdfec, XSDFEC_FEC_CODE_ADDR);
+	regread &= 0x1;
+	if (regread != xsdfec->config.code) {
+		dev_dbg(xsdfec->dev,
+			"%s SDFEC HW code does not match driver code, reg %d, code %d",
+			__func__, regread, xsdfec->config.code);
+		return -EINVAL;
+	}
+
+	/* Set AXIS enable */
+	xsdfec_regwrite(xsdfec, XSDFEC_AXIS_ENABLE_ADDR,
+			XSDFEC_AXIS_ENABLE_MASK);
+	/* Done */
+	xsdfec->state = XSDFEC_STARTED;
+	return 0;
+}
+
+static int xsdfec_stop(struct xsdfec_dev *xsdfec)
+{
+	u32 regread;
+
+	if (xsdfec->state != XSDFEC_STARTED)
+		dev_dbg(xsdfec->dev, "Device not started correctly");
+	/* Disable AXIS_ENABLE Input interfaces only */
+	regread = xsdfec_regread(xsdfec, XSDFEC_AXIS_ENABLE_ADDR);
+	regread &= (~XSDFEC_AXIS_IN_ENABLE_MASK);
+	xsdfec_regwrite(xsdfec, XSDFEC_AXIS_ENABLE_ADDR, regread);
+	/* Stop */
+	xsdfec->state = XSDFEC_STOPPED;
+	return 0;
+}
+
+static int xsdfec_clear_stats(struct xsdfec_dev *xsdfec)
+{
+	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
+	xsdfec->isr_err_count = 0;
+	xsdfec->uecc_count = 0;
+	xsdfec->cecc_count = 0;
+	spin_unlock_irqrestore(&xsdfec->error_data_lock, xsdfec->flags);
+
+	return 0;
+}
+
+static int xsdfec_get_stats(struct xsdfec_dev *xsdfec, void __user *arg)
+{
+	int err;
+	struct xsdfec_stats user_stats;
+
+	spin_lock_irqsave(&xsdfec->error_data_lock, xsdfec->flags);
+	user_stats.isr_err_count = xsdfec->isr_err_count;
+	user_stats.cecc_count = xsdfec->cecc_count;
+	user_stats.uecc_count = xsdfec->uecc_count;
+	xsdfec->stats_updated = false;
+	spin_unlock_irqrestore(&xsdfec->error_data_lock, xsdfec->flags);
+
+	err = copy_to_user(arg, &user_stats, sizeof(user_stats));
+	if (err)
+		err = -EFAULT;
+
+	return err;
+}
+
+static int xsdfec_set_default_config(struct xsdfec_dev *xsdfec)
+{
+	/* Ensure registers are aligned with core configuration */
+	xsdfec_regwrite(xsdfec, XSDFEC_FEC_CODE_ADDR, xsdfec->config.code);
+	xsdfec_cfg_axi_streams(xsdfec);
+	update_config_from_hw(xsdfec);
+
+	return 0;
+}
+
 static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 			     unsigned long data)
 {
@@ -849,6 +946,16 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 
 	xsdfec = container_of(fptr->private_data, struct xsdfec_dev, miscdev);
 
+	/* In failed state allow only reset and get status IOCTLs */
+	if (xsdfec->state == XSDFEC_NEEDS_RESET &&
+	    (cmd != XSDFEC_SET_DEFAULT_CONFIG && cmd != XSDFEC_GET_STATUS &&
+	     cmd != XSDFEC_GET_STATS && cmd != XSDFEC_CLEAR_STATS)) {
+		return -EPERM;
+	}
+
+	if (_IOC_TYPE(cmd) != XSDFEC_MAGIC)
+		return -ENOTTY;
+
 	/* check if ioctl argument is present and valid */
 	if (_IOC_DIR(cmd) != _IOC_NONE) {
 		arg = (void __user *)data;
@@ -857,9 +964,27 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
 	}
 
 	switch (cmd) {
+	case XSDFEC_START_DEV:
+		rval = xsdfec_start(xsdfec);
+		break;
+	case XSDFEC_STOP_DEV:
+		rval = xsdfec_stop(xsdfec);
+		break;
+	case XSDFEC_CLEAR_STATS:
+		rval = xsdfec_clear_stats(xsdfec);
+		break;
+	case XSDFEC_GET_STATS:
+		rval = xsdfec_get_stats(xsdfec, arg);
+		break;
+	case XSDFEC_GET_STATUS:
+		rval = xsdfec_get_status(xsdfec, arg);
+		break;
 	case XSDFEC_GET_CONFIG:
 		rval = xsdfec_get_config(xsdfec, arg);
 		break;
+	case XSDFEC_SET_DEFAULT_CONFIG:
+		rval = xsdfec_set_default_config(xsdfec);
+		break;
 	case XSDFEC_SET_IRQ:
 		rval = xsdfec_set_irq(xsdfec, arg);
 		break;
diff --git a/include/uapi/misc/xilinx_sdfec.h b/include/uapi/misc/xilinx_sdfec.h
index 85ee288..ee1a42ae 100644
--- a/include/uapi/misc/xilinx_sdfec.h
+++ b/include/uapi/misc/xilinx_sdfec.h
@@ -234,6 +234,21 @@ struct xsdfec_config {
 };
 
 /**
+ * struct xsdfec_stats - Stats retrived by ioctl XSDFEC_GET_STATS. Used
+ *			 to buffer atomic_t variables from struct
+ *			 xsdfec_dev. Counts are accumulated until
+ *			 the user clears them.
+ * @isr_err_count: Count of ISR errors
+ * @cecc_count: Count of Correctable ECC errors (SBE)
+ * @uecc_count: Count of Uncorrectable ECC errors (MBE)
+ */
+struct xsdfec_stats {
+	__u32 isr_err_count;
+	__u32 cecc_count;
+	__u32 uecc_count;
+};
+
+/**
  * struct xsdfec_ldpc_param_table_sizes - Used to store sizes of SD-FEC table
  *					  entries for an individual LPDC code
  *					  parameter.
@@ -252,6 +267,32 @@ struct xsdfec_ldpc_param_table_sizes {
  */
 #define XSDFEC_MAGIC 'f'
 /**
+ * DOC: XSDFEC_START_DEV
+ *
+ * @Description
+ *
+ * ioctl to start SD-FEC core
+ *
+ * This fails if the XSDFEC_SET_ORDER ioctl has not been previously called
+ */
+#define XSDFEC_START_DEV _IO(XSDFEC_MAGIC, 0)
+/**
+ * DOC: XSDFEC_STOP_DEV
+ *
+ * @Description
+ *
+ * ioctl to stop the SD-FEC core
+ */
+#define XSDFEC_STOP_DEV _IO(XSDFEC_MAGIC, 1)
+/**
+ * DOC: XSDFEC_GET_STATUS
+ *
+ * @Description
+ *
+ * ioctl that returns status of SD-FEC core
+ */
+#define XSDFEC_GET_STATUS _IOR(XSDFEC_MAGIC, 2, struct xsdfec_status)
+/**
  * DOC: XSDFEC_SET_IRQ
  * @Parameters
  *
@@ -370,4 +411,38 @@ struct xsdfec_ldpc_param_table_sizes {
  * ioctl that determines if SD-FEC is processing data
  */
 #define XSDFEC_IS_ACTIVE _IOR(XSDFEC_MAGIC, 10, bool)
+/**
+ * DOC: XSDFEC_CLEAR_STATS
+ *
+ * @Description
+ *
+ * ioctl that clears error stats collected during interrupts
+ */
+#define XSDFEC_CLEAR_STATS _IO(XSDFEC_MAGIC, 11)
+/**
+ * DOC: XSDFEC_GET_STATS
+ * @Parameters
+ *
+ * @struct xsdfec_stats *
+ *	Pointer to the &struct xsdfec_stats that will contain the updated stats
+ *	values
+ *
+ * @Description
+ *
+ * ioctl that returns SD-FEC core stats
+ *
+ * This can only be used when the driver is in the XSDFEC_STOPPED state
+ */
+#define XSDFEC_GET_STATS _IOR(XSDFEC_MAGIC, 12, struct xsdfec_stats)
+/**
+ * DOC: XSDFEC_SET_DEFAULT_CONFIG
+ *
+ * @Description
+ *
+ * ioctl that returns SD-FEC core to default config, use after a reset
+ *
+ * This can only be used when the driver is in the XSDFEC_STOPPED state
+ */
+#define XSDFEC_SET_DEFAULT_CONFIG _IO(XSDFEC_MAGIC, 13)
+
 #endif /* __XILINX_SDFEC_H__ */
-- 
2.7.4

[PATCH V8 7/8] Docs: misc: xilinx_sdfec: Add documentation

[Dragan Cvetic]

Add SD-FEC driver documentation.

Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 Documentation/misc-devices/index.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/misc-devices/index.rst b/Documentation/misc-devices/index.rst
index a57f92d..f11c5da 100644
--- a/Documentation/misc-devices/index.rst
+++ b/Documentation/misc-devices/index.rst
@@ -20,3 +20,4 @@ fit into other categories.
    isl29003
    lis3lv02d
    max6875
+   xilinx_sdfec
-- 
2.7.4

[PATCH V8 8/8] MAINTAINERS: add maintainer for SD-FEC

[Dragan Cvetic]

support

Add maintainer entry for Xilinx SD-FEC driver support.

Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
---
 MAINTAINERS | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 1fc7baf..6a9db56 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17402,6 +17402,17 @@ F:	Documentation/devicetree/bindings/media/xilinx/
 F:	drivers/media/platform/xilinx/
 F:	include/uapi/linux/xilinx-v4l2-controls.h
 
+XILINX SD-FEC IP CORES
+M:	Derek Kiernan <derek.kiernan@xilinx.com>
+M:	Dragan Cvetic <dragan.cvetic@xilinx.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/misc/xlnx,sd-fec.txt
+F:	Documentation/misc-devices/xilinx_sdfec.rst
+F:	drivers/misc/xilinx_sdfec.c
+F:	drivers/misc/Kconfig
+F:	drivers/misc/Makefile
+F:	include/uapi/misc/xilinx_sdfec.h
+
 XILLYBUS DRIVER
 M:	Eli Billauer <eli.billauer@gmail.com>
 L:	linux-kernel@vger.kernel.org
-- 
2.7.4

Re: [PATCH V8 7/8] Docs: misc: xilinx_sdfec: Add documentation

[Kees Cook]

On Sun, Jul 07, 2019 at 01:15:41AM +0100, Dragan Cvetic wrote:
> Add SD-FEC driver documentation.
> 
> Signed-off-by: Derek Kiernan <derek.kiernan@xilinx.com>
> Signed-off-by: Dragan Cvetic <dragan.cvetic@xilinx.com>
> ---
>  Documentation/misc-devices/index.rst | 1 +
>  1 file changed, 1 insertion(+)

Hi! It looks like Documentation/misc-devices/xilinx_sdfec.rst went
missing in this revision (and when committed upstream). It looks like it
was present at least in the V7 of the series:
https://lore.kernel.org/lkml/1560274185-264438-11-git-send-email-dragan.cvetic@xilinx.com/

-Kees

> 
> diff --git a/Documentation/misc-devices/index.rst b/Documentation/misc-devices/index.rst
> index a57f92d..f11c5da 100644
> --- a/Documentation/misc-devices/index.rst
> +++ b/Documentation/misc-devices/index.rst
> @@ -20,3 +20,4 @@ fit into other categories.
>     isl29003
>     lis3lv02d
>     max6875
> +   xilinx_sdfec
> -- 
> 2.7.4
> 

-- 
Kees Cook