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Diffstat (limited to 'drivers/char/xilinx_hwicap/fifo_icap.c')
-rw-r--r--drivers/char/xilinx_hwicap/fifo_icap.c393
1 files changed, 393 insertions, 0 deletions
diff --git a/drivers/char/xilinx_hwicap/fifo_icap.c b/drivers/char/xilinx_hwicap/fifo_icap.c
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--- /dev/null
+++ b/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));
+}
+
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