diff options
Diffstat (limited to 'kernel/drivers/char/xilinx_hwicap/fifo_icap.c')
| -rw-r--r-- | kernel/drivers/char/xilinx_hwicap/fifo_icap.c | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/kernel/drivers/char/xilinx_hwicap/fifo_icap.c b/kernel/drivers/char/xilinx_hwicap/fifo_icap.c new file mode 100644 index 000000000..02225eb19 --- /dev/null +++ b/kernel/drivers/char/xilinx_hwicap/fifo_icap.c @@ -0,0 +1,393 @@ +/***************************************************************************** + * + * 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); +} + +/** + * 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; +} + +/** + * 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); +} + +/** + * 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"); +} + +/** + * 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"); +} + +/** + * 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; +} + +/** + * 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; +} + +/** + * 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); +} + +/** + * 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); +} + +/** + * 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; +} + +/** + * 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; +} + +/** + * 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)); + +} + +/** + * 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)); +} + |