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Release 4.7 drivers/char/xilinx_hwicap/fifo_icap.c

/*****************************************************************************
 *
 *     Author: Xilinx, Inc.
 *
 *     This program is free software; you can redistribute it and/or modify it
 *     under the terms of the GNU General Public License as published by the
 *     Free Software Foundation; either version 2 of the License, or (at your
 *     option) any later version.
 *
 *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
 *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
 *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
 *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
 *     APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
 *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
 *     AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
 *     FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
 *     WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
 *     IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
 *     REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
 *     INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *     FOR A PARTICULAR PURPOSE.
 *
 *     (c) Copyright 2007-2008 Xilinx Inc.
 *     All rights reserved.
 *
 *     You should have received a copy of the GNU General Public License along
 *     with this program; if not, write to the Free Software Foundation, Inc.,
 *     675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *****************************************************************************/

#include "fifo_icap.h"

/* Register offsets for the XHwIcap device. */

#define XHI_GIER_OFFSET	0x1C  
/* Device Global Interrupt Enable Reg */

#define XHI_IPISR_OFFSET 0x20  
/* Interrupt Status Register */

#define XHI_IPIER_OFFSET 0x28  
/* Interrupt Enable Register */

#define XHI_WF_OFFSET 0x100 
/* Write FIFO */

#define XHI_RF_OFFSET 0x104 
/* Read FIFO */

#define XHI_SZ_OFFSET 0x108 
/* Size Register */

#define XHI_CR_OFFSET 0x10C 
/* Control Register */

#define XHI_SR_OFFSET 0x110 
/* Status Register */

#define XHI_WFV_OFFSET 0x114 
/* Write FIFO Vacancy Register */

#define XHI_RFO_OFFSET 0x118 
/* Read FIFO Occupancy Register */

/* Device Global Interrupt Enable Register (GIER) bit definitions */


#define XHI_GIER_GIE_MASK 0x80000000 
/* Global Interrupt enable Mask */

/**
 * HwIcap Device Interrupt Status/Enable Registers
 *
 * Interrupt Status Register (IPISR) : This register holds the
 * interrupt status flags for the device. These bits are toggle on
 * write.
 *
 * Interrupt Enable Register (IPIER) : This register is used to enable
 * interrupt sources for the device.
 * Writing a '1' to a bit enables the corresponding interrupt.
 * Writing a '0' to a bit disables the corresponding interrupt.
 *
 * IPISR/IPIER registers have the same bit definitions and are only defined
 * once.
 */

#define XHI_IPIXR_RFULL_MASK 0x00000008 
/* Read FIFO Full */

#define XHI_IPIXR_WEMPTY_MASK 0x00000004 
/* Write FIFO Empty */

#define XHI_IPIXR_RDP_MASK 0x00000002 
/* Read FIFO half full */

#define XHI_IPIXR_WRP_MASK 0x00000001 
/* Write FIFO half full */

#define XHI_IPIXR_ALL_MASK 0x0000000F 
/* Mask of all interrupts */

/* Control Register (CR) */

#define XHI_CR_SW_RESET_MASK 0x00000008 
/* SW Reset Mask */

#define XHI_CR_FIFO_CLR_MASK 0x00000004 
/* FIFO Clear Mask */

#define XHI_CR_READ_MASK 0x00000002 
/* Read from ICAP to FIFO */

#define XHI_CR_WRITE_MASK 0x00000001 
/* Write from FIFO to ICAP */



#define XHI_WFO_MAX_VACANCY 1024 
/* Max Write FIFO Vacancy, in words */

#define XHI_RFO_MAX_OCCUPANCY 256 
/* Max Read FIFO Occupancy, in words */
/* The maximum amount we can request from fifo_icap_get_configuration
   at once, in bytes. */

#define XHI_MAX_READ_TRANSACTION_WORDS 0xFFF


/**
 * fifo_icap_fifo_write - Write data to the write FIFO.
 * @drvdata: a pointer to the drvdata.
 * @data: the 32-bit value to be written to the FIFO.
 *
 * This function will silently fail if the fifo is full.
 **/

static inline void fifo_icap_fifo_write(struct hwicap_drvdata *drvdata, u32 data) { dev_dbg(drvdata->dev, "fifo_write: %x\n", data); out_be32(drvdata->base_address + XHI_WF_OFFSET, data); }

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/** * fifo_icap_fifo_read - Read data from the Read FIFO. * @drvdata: a pointer to the drvdata. * * This function will silently fail if the fifo is empty. **/
static inline u32 fifo_icap_fifo_read(struct hwicap_drvdata *drvdata) { u32 data = in_be32(drvdata->base_address + XHI_RF_OFFSET); dev_dbg(drvdata->dev, "fifo_read: %x\n", data); return data; }

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/** * fifo_icap_set_read_size - Set the the size register. * @drvdata: a pointer to the drvdata. * @data: the size of the following read transaction, in words. **/
static inline void fifo_icap_set_read_size(struct hwicap_drvdata *drvdata, u32 data) { out_be32(drvdata->base_address + XHI_SZ_OFFSET, data); }

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/** * fifo_icap_start_config - Initiate a configuration (write) to the device. * @drvdata: a pointer to the drvdata. **/
static inline void fifo_icap_start_config(struct hwicap_drvdata *drvdata) { out_be32(drvdata->base_address + XHI_CR_OFFSET, XHI_CR_WRITE_MASK); dev_dbg(drvdata->dev, "configuration started\n"); }

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/** * fifo_icap_start_readback - Initiate a readback from the device. * @drvdata: a pointer to the drvdata. **/
static inline void fifo_icap_start_readback(struct hwicap_drvdata *drvdata) { out_be32(drvdata->base_address + XHI_CR_OFFSET, XHI_CR_READ_MASK); dev_dbg(drvdata->dev, "readback started\n"); }

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/** * fifo_icap_get_status - Get the contents of the status register. * @drvdata: a pointer to the drvdata. * * The status register contains the ICAP status and the done bit. * * D8 - cfgerr * D7 - dalign * D6 - rip * D5 - in_abort_l * D4 - Always 1 * D3 - Always 1 * D2 - Always 1 * D1 - Always 1 * D0 - Done bit **/
u32 fifo_icap_get_status(struct hwicap_drvdata *drvdata) { u32 status = in_be32(drvdata->base_address + XHI_SR_OFFSET); dev_dbg(drvdata->dev, "Getting status = %x\n", status); return status; }

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/** * fifo_icap_busy - Return true if the ICAP is still processing a transaction. * @drvdata: a pointer to the drvdata. **/
static inline u32 fifo_icap_busy(struct hwicap_drvdata *drvdata) { u32 status = in_be32(drvdata->base_address + XHI_SR_OFFSET); return (status & XHI_SR_DONE_MASK) ? 0 : 1; }

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/** * fifo_icap_write_fifo_vacancy - Query the write fifo available space. * @drvdata: a pointer to the drvdata. * * Return the number of words that can be safely pushed into the write fifo. **/
static inline u32 fifo_icap_write_fifo_vacancy( struct hwicap_drvdata *drvdata) { return in_be32(drvdata->base_address + XHI_WFV_OFFSET); }

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/** * fifo_icap_read_fifo_occupancy - Query the read fifo available data. * @drvdata: a pointer to the drvdata. * * Return the number of words that can be safely read from the read fifo. **/
static inline u32 fifo_icap_read_fifo_occupancy( struct hwicap_drvdata *drvdata) { return in_be32(drvdata->base_address + XHI_RFO_OFFSET); }

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/** * fifo_icap_set_configuration - Send configuration data to the ICAP. * @drvdata: a pointer to the drvdata. * @frame_buffer: a pointer to the data to be written to the * ICAP device. * @num_words: the number of words (32 bit) to write to the ICAP * device. * This function writes the given user data to the Write FIFO in * polled mode and starts the transfer of the data to * the ICAP device. **/
int fifo_icap_set_configuration(struct hwicap_drvdata *drvdata, u32 *frame_buffer, u32 num_words) { u32 write_fifo_vacancy = 0; u32 retries = 0; u32 remaining_words; dev_dbg(drvdata->dev, "fifo_set_configuration\n"); /* * Check if the ICAP device is Busy with the last Read/Write */ if (fifo_icap_busy(drvdata)) return -EBUSY; /* * Set up the buffer pointer and the words to be transferred. */ remaining_words = num_words; while (remaining_words > 0) { /* * Wait until we have some data in the fifo. */ while (write_fifo_vacancy == 0) { write_fifo_vacancy = fifo_icap_write_fifo_vacancy(drvdata); retries++; if (retries > XHI_MAX_RETRIES) return -EIO; } /* * Write data into the Write FIFO. */ while ((write_fifo_vacancy != 0) && (remaining_words > 0)) { fifo_icap_fifo_write(drvdata, *frame_buffer); remaining_words--; write_fifo_vacancy--; frame_buffer++; } /* Start pushing whatever is in the FIFO into the ICAP. */ fifo_icap_start_config(drvdata); } /* Wait until the write has finished. */ while (fifo_icap_busy(drvdata)) { retries++; if (retries > XHI_MAX_RETRIES) break; } dev_dbg(drvdata->dev, "done fifo_set_configuration\n"); /* * If the requested number of words have not been read from * the device then indicate failure. */ if (remaining_words != 0) return -EIO; return 0; }

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/** * fifo_icap_get_configuration - Read configuration data from the device. * @drvdata: a pointer to the drvdata. * @data: Address of the data representing the partial bitstream * @size: the size of the partial bitstream in 32 bit words. * * This function reads the specified number of words from the ICAP device in * the polled mode. */
int fifo_icap_get_configuration(struct hwicap_drvdata *drvdata, u32 *frame_buffer, u32 num_words) { u32 read_fifo_occupancy = 0; u32 retries = 0; u32 *data = frame_buffer; u32 remaining_words; u32 words_to_read; dev_dbg(drvdata->dev, "fifo_get_configuration\n"); /* * Check if the ICAP device is Busy with the last Write/Read */ if (fifo_icap_busy(drvdata)) return -EBUSY; remaining_words = num_words; while (remaining_words > 0) { words_to_read = remaining_words; /* The hardware has a limit on the number of words that can be read at one time. */ if (words_to_read > XHI_MAX_READ_TRANSACTION_WORDS) words_to_read = XHI_MAX_READ_TRANSACTION_WORDS; remaining_words -= words_to_read; fifo_icap_set_read_size(drvdata, words_to_read); fifo_icap_start_readback(drvdata); while (words_to_read > 0) { /* Wait until we have some data in the fifo. */ while (read_fifo_occupancy == 0) { read_fifo_occupancy = fifo_icap_read_fifo_occupancy(drvdata); retries++; if (retries > XHI_MAX_RETRIES) return -EIO; } if (read_fifo_occupancy > words_to_read) read_fifo_occupancy = words_to_read; words_to_read -= read_fifo_occupancy; /* Read the data from the Read FIFO. */ while (read_fifo_occupancy != 0) { *data++ = fifo_icap_fifo_read(drvdata); read_fifo_occupancy--; } } } dev_dbg(drvdata->dev, "done fifo_get_configuration\n"); return 0; }

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/** * buffer_icap_reset - Reset the logic of the icap device. * @drvdata: a pointer to the drvdata. * * This function forces the software reset of the complete HWICAP device. * All the registers will return to the default value and the FIFO is also * flushed as a part of this software reset. */
void fifo_icap_reset(struct hwicap_drvdata *drvdata) { u32 reg_data; /* * Reset the device by setting/clearing the RESET bit in the * Control Register. */ reg_data = in_be32(drvdata->base_address + XHI_CR_OFFSET); out_be32(drvdata->base_address + XHI_CR_OFFSET, reg_data | XHI_CR_SW_RESET_MASK); out_be32(drvdata->base_address + XHI_CR_OFFSET, reg_data & (~XHI_CR_SW_RESET_MASK)); }

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/** * fifo_icap_flush_fifo - This function flushes the FIFOs in the device. * @drvdata: a pointer to the drvdata. */
void fifo_icap_flush_fifo(struct hwicap_drvdata *drvdata) { u32 reg_data; /* * Flush the FIFO by setting/clearing the FIFO Clear bit in the * Control Register. */ reg_data = in_be32(drvdata->base_address + XHI_CR_OFFSET); out_be32(drvdata->base_address + XHI_CR_OFFSET, reg_data | XHI_CR_FIFO_CLR_MASK); out_be32(drvdata->base_address + XHI_CR_OFFSET, reg_data & (~XHI_CR_FIFO_CLR_MASK)); }

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