14a965c5fSJacob Feder // SPDX-License-Identifier: GPL-2.0
24a965c5fSJacob Feder /*
34a965c5fSJacob Feder * Xilinx AXIS FIFO: interface to the Xilinx AXI-Stream FIFO IP core
44a965c5fSJacob Feder *
54a965c5fSJacob Feder * Copyright (C) 2018 Jacob Feder
64a965c5fSJacob Feder *
74a965c5fSJacob Feder * Authors: Jacob Feder <jacobsfeder@gmail.com>
84a965c5fSJacob Feder *
94a965c5fSJacob Feder * See Xilinx PG080 document for IP details
104a965c5fSJacob Feder */
114a965c5fSJacob Feder
124a965c5fSJacob Feder /* ----------------------------
134a965c5fSJacob Feder * includes
144a965c5fSJacob Feder * ----------------------------
154a965c5fSJacob Feder */
164a965c5fSJacob Feder
174a965c5fSJacob Feder #include <linux/kernel.h>
18*decb929fSRob Herring #include <linux/of.h>
19*decb929fSRob Herring #include <linux/platform_device.h>
204a965c5fSJacob Feder #include <linux/wait.h>
210443b3f4SQuentin Deslandes #include <linux/mutex.h>
224a965c5fSJacob Feder #include <linux/device.h>
234a965c5fSJacob Feder #include <linux/cdev.h>
244a965c5fSJacob Feder #include <linux/init.h>
254a965c5fSJacob Feder #include <linux/module.h>
264a965c5fSJacob Feder #include <linux/slab.h>
274a965c5fSJacob Feder #include <linux/io.h>
284a965c5fSJacob Feder #include <linux/moduleparam.h>
294a965c5fSJacob Feder #include <linux/interrupt.h>
304a965c5fSJacob Feder #include <linux/param.h>
314a965c5fSJacob Feder #include <linux/fs.h>
324a965c5fSJacob Feder #include <linux/types.h>
334a965c5fSJacob Feder #include <linux/uaccess.h>
344a965c5fSJacob Feder #include <linux/jiffies.h>
35d2d7aa53SGreg Kroah-Hartman #include <linux/miscdevice.h>
364a965c5fSJacob Feder
374a965c5fSJacob Feder /* ----------------------------
384a965c5fSJacob Feder * driver parameters
394a965c5fSJacob Feder * ----------------------------
404a965c5fSJacob Feder */
414a965c5fSJacob Feder
424a965c5fSJacob Feder #define DRIVER_NAME "axis_fifo"
434a965c5fSJacob Feder
444a965c5fSJacob Feder #define READ_BUF_SIZE 128U /* read buffer length in words */
454a965c5fSJacob Feder #define WRITE_BUF_SIZE 128U /* write buffer length in words */
464a965c5fSJacob Feder
474a965c5fSJacob Feder /* ----------------------------
484a965c5fSJacob Feder * IP register offsets
494a965c5fSJacob Feder * ----------------------------
504a965c5fSJacob Feder */
514a965c5fSJacob Feder
524a965c5fSJacob Feder #define XLLF_ISR_OFFSET 0x00000000 /* Interrupt Status */
534a965c5fSJacob Feder #define XLLF_IER_OFFSET 0x00000004 /* Interrupt Enable */
544a965c5fSJacob Feder
554a965c5fSJacob Feder #define XLLF_TDFR_OFFSET 0x00000008 /* Transmit Reset */
564a965c5fSJacob Feder #define XLLF_TDFV_OFFSET 0x0000000c /* Transmit Vacancy */
574a965c5fSJacob Feder #define XLLF_TDFD_OFFSET 0x00000010 /* Transmit Data */
584a965c5fSJacob Feder #define XLLF_TLR_OFFSET 0x00000014 /* Transmit Length */
594a965c5fSJacob Feder
604a965c5fSJacob Feder #define XLLF_RDFR_OFFSET 0x00000018 /* Receive Reset */
614a965c5fSJacob Feder #define XLLF_RDFO_OFFSET 0x0000001c /* Receive Occupancy */
624a965c5fSJacob Feder #define XLLF_RDFD_OFFSET 0x00000020 /* Receive Data */
634a965c5fSJacob Feder #define XLLF_RLR_OFFSET 0x00000024 /* Receive Length */
644a965c5fSJacob Feder #define XLLF_SRR_OFFSET 0x00000028 /* Local Link Reset */
654a965c5fSJacob Feder #define XLLF_TDR_OFFSET 0x0000002C /* Transmit Destination */
664a965c5fSJacob Feder #define XLLF_RDR_OFFSET 0x00000030 /* Receive Destination */
674a965c5fSJacob Feder
684a965c5fSJacob Feder /* ----------------------------
694a965c5fSJacob Feder * reset register masks
704a965c5fSJacob Feder * ----------------------------
714a965c5fSJacob Feder */
724a965c5fSJacob Feder
734a965c5fSJacob Feder #define XLLF_RDFR_RESET_MASK 0x000000a5 /* receive reset value */
744a965c5fSJacob Feder #define XLLF_TDFR_RESET_MASK 0x000000a5 /* Transmit reset value */
754a965c5fSJacob Feder #define XLLF_SRR_RESET_MASK 0x000000a5 /* Local Link reset value */
764a965c5fSJacob Feder
774a965c5fSJacob Feder /* ----------------------------
784a965c5fSJacob Feder * interrupt masks
794a965c5fSJacob Feder * ----------------------------
804a965c5fSJacob Feder */
814a965c5fSJacob Feder
824a965c5fSJacob Feder #define XLLF_INT_RPURE_MASK 0x80000000 /* Receive under-read */
834a965c5fSJacob Feder #define XLLF_INT_RPORE_MASK 0x40000000 /* Receive over-read */
844a965c5fSJacob Feder #define XLLF_INT_RPUE_MASK 0x20000000 /* Receive underrun (empty) */
854a965c5fSJacob Feder #define XLLF_INT_TPOE_MASK 0x10000000 /* Transmit overrun */
864a965c5fSJacob Feder #define XLLF_INT_TC_MASK 0x08000000 /* Transmit complete */
874a965c5fSJacob Feder #define XLLF_INT_RC_MASK 0x04000000 /* Receive complete */
884a965c5fSJacob Feder #define XLLF_INT_TSE_MASK 0x02000000 /* Transmit length mismatch */
894a965c5fSJacob Feder #define XLLF_INT_TRC_MASK 0x01000000 /* Transmit reset complete */
904a965c5fSJacob Feder #define XLLF_INT_RRC_MASK 0x00800000 /* Receive reset complete */
914a965c5fSJacob Feder #define XLLF_INT_TFPF_MASK 0x00400000 /* Tx FIFO Programmable Full */
924a965c5fSJacob Feder #define XLLF_INT_TFPE_MASK 0x00200000 /* Tx FIFO Programmable Empty */
934a965c5fSJacob Feder #define XLLF_INT_RFPF_MASK 0x00100000 /* Rx FIFO Programmable Full */
944a965c5fSJacob Feder #define XLLF_INT_RFPE_MASK 0x00080000 /* Rx FIFO Programmable Empty */
954a965c5fSJacob Feder #define XLLF_INT_ALL_MASK 0xfff80000 /* All the ints */
964a965c5fSJacob Feder #define XLLF_INT_ERROR_MASK 0xf2000000 /* Error status ints */
974a965c5fSJacob Feder #define XLLF_INT_RXERROR_MASK 0xe0000000 /* Receive Error status ints */
984a965c5fSJacob Feder #define XLLF_INT_TXERROR_MASK 0x12000000 /* Transmit Error status ints */
994a965c5fSJacob Feder
1004a965c5fSJacob Feder /* ----------------------------
1014a965c5fSJacob Feder * globals
1024a965c5fSJacob Feder * ----------------------------
1034a965c5fSJacob Feder */
104752cbd8fSKhadija Kamran static long read_timeout = 1000; /* ms to wait before read() times out */
105752cbd8fSKhadija Kamran static long write_timeout = 1000; /* ms to wait before write() times out */
1064a965c5fSJacob Feder
1074a965c5fSJacob Feder /* ----------------------------
1084a965c5fSJacob Feder * module command-line arguments
1094a965c5fSJacob Feder * ----------------------------
1104a965c5fSJacob Feder */
1114a965c5fSJacob Feder
112752cbd8fSKhadija Kamran module_param(read_timeout, long, 0444);
1134a965c5fSJacob Feder MODULE_PARM_DESC(read_timeout, "ms to wait before blocking read() timing out; set to -1 for no timeout");
114752cbd8fSKhadija Kamran module_param(write_timeout, long, 0444);
1154a965c5fSJacob Feder MODULE_PARM_DESC(write_timeout, "ms to wait before blocking write() timing out; set to -1 for no timeout");
1164a965c5fSJacob Feder
1174a965c5fSJacob Feder /* ----------------------------
1184a965c5fSJacob Feder * types
1194a965c5fSJacob Feder * ----------------------------
1204a965c5fSJacob Feder */
1214a965c5fSJacob Feder
1224a965c5fSJacob Feder struct axis_fifo {
1234a965c5fSJacob Feder int irq; /* interrupt */
1244a965c5fSJacob Feder void __iomem *base_addr; /* kernel space memory */
1254a965c5fSJacob Feder
1264a965c5fSJacob Feder unsigned int rx_fifo_depth; /* max words in the receive fifo */
1274a965c5fSJacob Feder unsigned int tx_fifo_depth; /* max words in the transmit fifo */
1284a965c5fSJacob Feder int has_rx_fifo; /* whether the IP has the rx fifo enabled */
1294a965c5fSJacob Feder int has_tx_fifo; /* whether the IP has the tx fifo enabled */
1304a965c5fSJacob Feder
1314a965c5fSJacob Feder wait_queue_head_t read_queue; /* wait queue for asynchronos read */
1320443b3f4SQuentin Deslandes struct mutex read_lock; /* lock for reading */
1334a965c5fSJacob Feder wait_queue_head_t write_queue; /* wait queue for asynchronos write */
1340443b3f4SQuentin Deslandes struct mutex write_lock; /* lock for writing */
1354a965c5fSJacob Feder unsigned int write_flags; /* write file flags */
1364a965c5fSJacob Feder unsigned int read_flags; /* read file flags */
1374a965c5fSJacob Feder
1384a965c5fSJacob Feder struct device *dt_device; /* device created from the device tree */
139d2d7aa53SGreg Kroah-Hartman struct miscdevice miscdev;
1404a965c5fSJacob Feder };
1414a965c5fSJacob Feder
1424a965c5fSJacob Feder /* ----------------------------
1434a965c5fSJacob Feder * sysfs entries
1444a965c5fSJacob Feder * ----------------------------
1454a965c5fSJacob Feder */
1464a965c5fSJacob Feder
sysfs_write(struct device * dev,const char * buf,size_t count,unsigned int addr_offset)1474a965c5fSJacob Feder static ssize_t sysfs_write(struct device *dev, const char *buf,
1484a965c5fSJacob Feder size_t count, unsigned int addr_offset)
1494a965c5fSJacob Feder {
1504a965c5fSJacob Feder struct axis_fifo *fifo = dev_get_drvdata(dev);
1514a965c5fSJacob Feder unsigned long tmp;
1524a965c5fSJacob Feder int rc;
1534a965c5fSJacob Feder
1544a965c5fSJacob Feder rc = kstrtoul(buf, 0, &tmp);
1554a965c5fSJacob Feder if (rc < 0)
1564a965c5fSJacob Feder return rc;
1574a965c5fSJacob Feder
1584a965c5fSJacob Feder iowrite32(tmp, fifo->base_addr + addr_offset);
1594a965c5fSJacob Feder
1604a965c5fSJacob Feder return count;
1614a965c5fSJacob Feder }
1624a965c5fSJacob Feder
sysfs_read(struct device * dev,char * buf,unsigned int addr_offset)1634a965c5fSJacob Feder static ssize_t sysfs_read(struct device *dev, char *buf,
1644a965c5fSJacob Feder unsigned int addr_offset)
1654a965c5fSJacob Feder {
1664a965c5fSJacob Feder struct axis_fifo *fifo = dev_get_drvdata(dev);
1674a965c5fSJacob Feder unsigned int read_val;
1684a965c5fSJacob Feder unsigned int len;
1694a965c5fSJacob Feder char tmp[32];
1704a965c5fSJacob Feder
1714a965c5fSJacob Feder read_val = ioread32(fifo->base_addr + addr_offset);
1724a965c5fSJacob Feder len = snprintf(tmp, sizeof(tmp), "0x%x\n", read_val);
1734a965c5fSJacob Feder memcpy(buf, tmp, len);
1744a965c5fSJacob Feder
1754a965c5fSJacob Feder return len;
1764a965c5fSJacob Feder }
1774a965c5fSJacob Feder
isr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1784a965c5fSJacob Feder static ssize_t isr_store(struct device *dev, struct device_attribute *attr,
1794a965c5fSJacob Feder const char *buf, size_t count)
1804a965c5fSJacob Feder {
1814a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_ISR_OFFSET);
1824a965c5fSJacob Feder }
1834a965c5fSJacob Feder
isr_show(struct device * dev,struct device_attribute * attr,char * buf)1844a965c5fSJacob Feder static ssize_t isr_show(struct device *dev,
1854a965c5fSJacob Feder struct device_attribute *attr, char *buf)
1864a965c5fSJacob Feder {
1874a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_ISR_OFFSET);
1884a965c5fSJacob Feder }
1894a965c5fSJacob Feder
1904a965c5fSJacob Feder static DEVICE_ATTR_RW(isr);
1914a965c5fSJacob Feder
ier_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1924a965c5fSJacob Feder static ssize_t ier_store(struct device *dev, struct device_attribute *attr,
1934a965c5fSJacob Feder const char *buf, size_t count)
1944a965c5fSJacob Feder {
1954a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_IER_OFFSET);
1964a965c5fSJacob Feder }
1974a965c5fSJacob Feder
ier_show(struct device * dev,struct device_attribute * attr,char * buf)1984a965c5fSJacob Feder static ssize_t ier_show(struct device *dev,
1994a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2004a965c5fSJacob Feder {
2014a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_IER_OFFSET);
2024a965c5fSJacob Feder }
2034a965c5fSJacob Feder
2044a965c5fSJacob Feder static DEVICE_ATTR_RW(ier);
2054a965c5fSJacob Feder
tdfr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2064a965c5fSJacob Feder static ssize_t tdfr_store(struct device *dev, struct device_attribute *attr,
2074a965c5fSJacob Feder const char *buf, size_t count)
2084a965c5fSJacob Feder {
2094a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_TDFR_OFFSET);
2104a965c5fSJacob Feder }
2114a965c5fSJacob Feder
2124a965c5fSJacob Feder static DEVICE_ATTR_WO(tdfr);
2134a965c5fSJacob Feder
tdfv_show(struct device * dev,struct device_attribute * attr,char * buf)2144a965c5fSJacob Feder static ssize_t tdfv_show(struct device *dev,
2154a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2164a965c5fSJacob Feder {
2174a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_TDFV_OFFSET);
2184a965c5fSJacob Feder }
2194a965c5fSJacob Feder
2204a965c5fSJacob Feder static DEVICE_ATTR_RO(tdfv);
2214a965c5fSJacob Feder
tdfd_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2224a965c5fSJacob Feder static ssize_t tdfd_store(struct device *dev, struct device_attribute *attr,
2234a965c5fSJacob Feder const char *buf, size_t count)
2244a965c5fSJacob Feder {
2254a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_TDFD_OFFSET);
2264a965c5fSJacob Feder }
2274a965c5fSJacob Feder
2284a965c5fSJacob Feder static DEVICE_ATTR_WO(tdfd);
2294a965c5fSJacob Feder
tlr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2304a965c5fSJacob Feder static ssize_t tlr_store(struct device *dev, struct device_attribute *attr,
2314a965c5fSJacob Feder const char *buf, size_t count)
2324a965c5fSJacob Feder {
2334a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_TLR_OFFSET);
2344a965c5fSJacob Feder }
2354a965c5fSJacob Feder
2364a965c5fSJacob Feder static DEVICE_ATTR_WO(tlr);
2374a965c5fSJacob Feder
rdfr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2384a965c5fSJacob Feder static ssize_t rdfr_store(struct device *dev, struct device_attribute *attr,
2394a965c5fSJacob Feder const char *buf, size_t count)
2404a965c5fSJacob Feder {
2414a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_RDFR_OFFSET);
2424a965c5fSJacob Feder }
2434a965c5fSJacob Feder
2444a965c5fSJacob Feder static DEVICE_ATTR_WO(rdfr);
2454a965c5fSJacob Feder
rdfo_show(struct device * dev,struct device_attribute * attr,char * buf)2464a965c5fSJacob Feder static ssize_t rdfo_show(struct device *dev,
2474a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2484a965c5fSJacob Feder {
2494a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_RDFO_OFFSET);
2504a965c5fSJacob Feder }
2514a965c5fSJacob Feder
2524a965c5fSJacob Feder static DEVICE_ATTR_RO(rdfo);
2534a965c5fSJacob Feder
rdfd_show(struct device * dev,struct device_attribute * attr,char * buf)2544a965c5fSJacob Feder static ssize_t rdfd_show(struct device *dev,
2554a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2564a965c5fSJacob Feder {
2574a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_RDFD_OFFSET);
2584a965c5fSJacob Feder }
2594a965c5fSJacob Feder
2604a965c5fSJacob Feder static DEVICE_ATTR_RO(rdfd);
2614a965c5fSJacob Feder
rlr_show(struct device * dev,struct device_attribute * attr,char * buf)2624a965c5fSJacob Feder static ssize_t rlr_show(struct device *dev,
2634a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2644a965c5fSJacob Feder {
2654a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_RLR_OFFSET);
2664a965c5fSJacob Feder }
2674a965c5fSJacob Feder
2684a965c5fSJacob Feder static DEVICE_ATTR_RO(rlr);
2694a965c5fSJacob Feder
srr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2704a965c5fSJacob Feder static ssize_t srr_store(struct device *dev, struct device_attribute *attr,
2714a965c5fSJacob Feder const char *buf, size_t count)
2724a965c5fSJacob Feder {
2734a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_SRR_OFFSET);
2744a965c5fSJacob Feder }
2754a965c5fSJacob Feder
2764a965c5fSJacob Feder static DEVICE_ATTR_WO(srr);
2774a965c5fSJacob Feder
tdr_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2784a965c5fSJacob Feder static ssize_t tdr_store(struct device *dev, struct device_attribute *attr,
2794a965c5fSJacob Feder const char *buf, size_t count)
2804a965c5fSJacob Feder {
2814a965c5fSJacob Feder return sysfs_write(dev, buf, count, XLLF_TDR_OFFSET);
2824a965c5fSJacob Feder }
2834a965c5fSJacob Feder
2844a965c5fSJacob Feder static DEVICE_ATTR_WO(tdr);
2854a965c5fSJacob Feder
rdr_show(struct device * dev,struct device_attribute * attr,char * buf)2864a965c5fSJacob Feder static ssize_t rdr_show(struct device *dev,
2874a965c5fSJacob Feder struct device_attribute *attr, char *buf)
2884a965c5fSJacob Feder {
2894a965c5fSJacob Feder return sysfs_read(dev, buf, XLLF_RDR_OFFSET);
2904a965c5fSJacob Feder }
2914a965c5fSJacob Feder
2924a965c5fSJacob Feder static DEVICE_ATTR_RO(rdr);
2934a965c5fSJacob Feder
2944a965c5fSJacob Feder static struct attribute *axis_fifo_attrs[] = {
2954a965c5fSJacob Feder &dev_attr_isr.attr,
2964a965c5fSJacob Feder &dev_attr_ier.attr,
2974a965c5fSJacob Feder &dev_attr_tdfr.attr,
2984a965c5fSJacob Feder &dev_attr_tdfv.attr,
2994a965c5fSJacob Feder &dev_attr_tdfd.attr,
3004a965c5fSJacob Feder &dev_attr_tlr.attr,
3014a965c5fSJacob Feder &dev_attr_rdfr.attr,
3024a965c5fSJacob Feder &dev_attr_rdfo.attr,
3034a965c5fSJacob Feder &dev_attr_rdfd.attr,
3044a965c5fSJacob Feder &dev_attr_rlr.attr,
3054a965c5fSJacob Feder &dev_attr_srr.attr,
3064a965c5fSJacob Feder &dev_attr_tdr.attr,
3074a965c5fSJacob Feder &dev_attr_rdr.attr,
3084a965c5fSJacob Feder NULL,
3094a965c5fSJacob Feder };
3104a965c5fSJacob Feder
3114a965c5fSJacob Feder static const struct attribute_group axis_fifo_attrs_group = {
3124a965c5fSJacob Feder .name = "ip_registers",
3134a965c5fSJacob Feder .attrs = axis_fifo_attrs,
3144a965c5fSJacob Feder };
3154a965c5fSJacob Feder
316d2d7aa53SGreg Kroah-Hartman static const struct attribute_group *axis_fifo_attrs_groups[] = {
317d2d7aa53SGreg Kroah-Hartman &axis_fifo_attrs_group,
318d2d7aa53SGreg Kroah-Hartman NULL,
319d2d7aa53SGreg Kroah-Hartman };
320d2d7aa53SGreg Kroah-Hartman
3214a965c5fSJacob Feder /* ----------------------------
3224a965c5fSJacob Feder * implementation
3234a965c5fSJacob Feder * ----------------------------
3244a965c5fSJacob Feder */
3254a965c5fSJacob Feder
reset_ip_core(struct axis_fifo * fifo)3264a965c5fSJacob Feder static void reset_ip_core(struct axis_fifo *fifo)
3274a965c5fSJacob Feder {
3284a965c5fSJacob Feder iowrite32(XLLF_SRR_RESET_MASK, fifo->base_addr + XLLF_SRR_OFFSET);
3294a965c5fSJacob Feder iowrite32(XLLF_TDFR_RESET_MASK, fifo->base_addr + XLLF_TDFR_OFFSET);
3304a965c5fSJacob Feder iowrite32(XLLF_RDFR_RESET_MASK, fifo->base_addr + XLLF_RDFR_OFFSET);
3314a965c5fSJacob Feder iowrite32(XLLF_INT_TC_MASK | XLLF_INT_RC_MASK | XLLF_INT_RPURE_MASK |
3324a965c5fSJacob Feder XLLF_INT_RPORE_MASK | XLLF_INT_RPUE_MASK |
3334a965c5fSJacob Feder XLLF_INT_TPOE_MASK | XLLF_INT_TSE_MASK,
3344a965c5fSJacob Feder fifo->base_addr + XLLF_IER_OFFSET);
3354a965c5fSJacob Feder iowrite32(XLLF_INT_ALL_MASK, fifo->base_addr + XLLF_ISR_OFFSET);
3364a965c5fSJacob Feder }
3374a965c5fSJacob Feder
3380443b3f4SQuentin Deslandes /**
339bbf40b2fSLee Jones * axis_fifo_read() - Read a packet from AXIS-FIFO character device.
340c848434cSLee Jones * @f: Open file.
341c848434cSLee Jones * @buf: User space buffer to read to.
342c848434cSLee Jones * @len: User space buffer length.
343c848434cSLee Jones * @off: Buffer offset.
3440443b3f4SQuentin Deslandes *
3450443b3f4SQuentin Deslandes * As defined by the device's documentation, we need to check the device's
3460443b3f4SQuentin Deslandes * occupancy before reading the length register and then the data. All these
3470443b3f4SQuentin Deslandes * operations must be executed atomically, in order and one after the other
3480443b3f4SQuentin Deslandes * without missing any.
3490443b3f4SQuentin Deslandes *
3500443b3f4SQuentin Deslandes * Returns the number of bytes read from the device or negative error code
3510443b3f4SQuentin Deslandes * on failure.
3520443b3f4SQuentin Deslandes */
axis_fifo_read(struct file * f,char __user * buf,size_t len,loff_t * off)3534a965c5fSJacob Feder static ssize_t axis_fifo_read(struct file *f, char __user *buf,
3544a965c5fSJacob Feder size_t len, loff_t *off)
3554a965c5fSJacob Feder {
3564a965c5fSJacob Feder struct axis_fifo *fifo = (struct axis_fifo *)f->private_data;
3574a965c5fSJacob Feder size_t bytes_available;
3584a965c5fSJacob Feder unsigned int words_available;
3594a965c5fSJacob Feder unsigned int copied;
3604a965c5fSJacob Feder unsigned int copy;
3614a965c5fSJacob Feder unsigned int i;
3624a965c5fSJacob Feder int ret;
3634a965c5fSJacob Feder u32 tmp_buf[READ_BUF_SIZE];
3644a965c5fSJacob Feder
3654a965c5fSJacob Feder if (fifo->read_flags & O_NONBLOCK) {
3660443b3f4SQuentin Deslandes /*
3670443b3f4SQuentin Deslandes * Device opened in non-blocking mode. Try to lock it and then
3680443b3f4SQuentin Deslandes * check if any packet is available.
3694a965c5fSJacob Feder */
3700443b3f4SQuentin Deslandes if (!mutex_trylock(&fifo->read_lock))
3714a965c5fSJacob Feder return -EAGAIN;
3720443b3f4SQuentin Deslandes
3730443b3f4SQuentin Deslandes if (!ioread32(fifo->base_addr + XLLF_RDFO_OFFSET)) {
3740443b3f4SQuentin Deslandes ret = -EAGAIN;
3750443b3f4SQuentin Deslandes goto end_unlock;
3760443b3f4SQuentin Deslandes }
3774a965c5fSJacob Feder } else {
3784a965c5fSJacob Feder /* opened in blocking mode
3794a965c5fSJacob Feder * wait for a packet available interrupt (or timeout)
3804a965c5fSJacob Feder * if nothing is currently available
3814a965c5fSJacob Feder */
3820443b3f4SQuentin Deslandes mutex_lock(&fifo->read_lock);
3830443b3f4SQuentin Deslandes ret = wait_event_interruptible_timeout(fifo->read_queue,
3844a965c5fSJacob Feder ioread32(fifo->base_addr + XLLF_RDFO_OFFSET),
385752cbd8fSKhadija Kamran read_timeout);
3864a965c5fSJacob Feder
3870443b3f4SQuentin Deslandes if (ret <= 0) {
3884a965c5fSJacob Feder if (ret == 0) {
3890443b3f4SQuentin Deslandes ret = -EAGAIN;
3900443b3f4SQuentin Deslandes } else if (ret != -ERESTARTSYS) {
3914a965c5fSJacob Feder dev_err(fifo->dt_device, "wait_event_interruptible_timeout() error in read (ret=%i)\n",
3924a965c5fSJacob Feder ret);
3930443b3f4SQuentin Deslandes }
3940443b3f4SQuentin Deslandes
3950443b3f4SQuentin Deslandes goto end_unlock;
3964a965c5fSJacob Feder }
3974a965c5fSJacob Feder }
3984a965c5fSJacob Feder
3994a965c5fSJacob Feder bytes_available = ioread32(fifo->base_addr + XLLF_RLR_OFFSET);
4004a965c5fSJacob Feder if (!bytes_available) {
4014a965c5fSJacob Feder dev_err(fifo->dt_device, "received a packet of length 0 - fifo core will be reset\n");
4024a965c5fSJacob Feder reset_ip_core(fifo);
4030443b3f4SQuentin Deslandes ret = -EIO;
4040443b3f4SQuentin Deslandes goto end_unlock;
4054a965c5fSJacob Feder }
4064a965c5fSJacob Feder
4074a965c5fSJacob Feder if (bytes_available > len) {
4084a965c5fSJacob Feder dev_err(fifo->dt_device, "user read buffer too small (available bytes=%zu user buffer bytes=%zu) - fifo core will be reset\n",
4094a965c5fSJacob Feder bytes_available, len);
4104a965c5fSJacob Feder reset_ip_core(fifo);
4110443b3f4SQuentin Deslandes ret = -EINVAL;
4120443b3f4SQuentin Deslandes goto end_unlock;
4134a965c5fSJacob Feder }
4144a965c5fSJacob Feder
4154a965c5fSJacob Feder if (bytes_available % sizeof(u32)) {
4164a965c5fSJacob Feder /* this probably can't happen unless IP
4174a965c5fSJacob Feder * registers were previously mishandled
4184a965c5fSJacob Feder */
4194a965c5fSJacob Feder dev_err(fifo->dt_device, "received a packet that isn't word-aligned - fifo core will be reset\n");
4204a965c5fSJacob Feder reset_ip_core(fifo);
4210443b3f4SQuentin Deslandes ret = -EIO;
4220443b3f4SQuentin Deslandes goto end_unlock;
4234a965c5fSJacob Feder }
4244a965c5fSJacob Feder
4254a965c5fSJacob Feder words_available = bytes_available / sizeof(u32);
4264a965c5fSJacob Feder
4274a965c5fSJacob Feder /* read data into an intermediate buffer, copying the contents
4284a965c5fSJacob Feder * to userspace when the buffer is full
4294a965c5fSJacob Feder */
4304a965c5fSJacob Feder copied = 0;
4314a965c5fSJacob Feder while (words_available > 0) {
4324a965c5fSJacob Feder copy = min(words_available, READ_BUF_SIZE);
4334a965c5fSJacob Feder
4344a965c5fSJacob Feder for (i = 0; i < copy; i++) {
4354a965c5fSJacob Feder tmp_buf[i] = ioread32(fifo->base_addr +
4364a965c5fSJacob Feder XLLF_RDFD_OFFSET);
4374a965c5fSJacob Feder }
4384a965c5fSJacob Feder
4394a965c5fSJacob Feder if (copy_to_user(buf + copied * sizeof(u32), tmp_buf,
4404a965c5fSJacob Feder copy * sizeof(u32))) {
4414a965c5fSJacob Feder reset_ip_core(fifo);
4420443b3f4SQuentin Deslandes ret = -EFAULT;
4430443b3f4SQuentin Deslandes goto end_unlock;
4444a965c5fSJacob Feder }
4454a965c5fSJacob Feder
4464a965c5fSJacob Feder copied += copy;
4474a965c5fSJacob Feder words_available -= copy;
4484a965c5fSJacob Feder }
4494a965c5fSJacob Feder
4500443b3f4SQuentin Deslandes ret = bytes_available;
4510443b3f4SQuentin Deslandes
4520443b3f4SQuentin Deslandes end_unlock:
4530443b3f4SQuentin Deslandes mutex_unlock(&fifo->read_lock);
4540443b3f4SQuentin Deslandes
4550443b3f4SQuentin Deslandes return ret;
4564a965c5fSJacob Feder }
4574a965c5fSJacob Feder
4580443b3f4SQuentin Deslandes /**
4590443b3f4SQuentin Deslandes * axis_fifo_write() - Write buffer to AXIS-FIFO character device.
460c848434cSLee Jones * @f: Open file.
461c848434cSLee Jones * @buf: User space buffer to write to the device.
462c848434cSLee Jones * @len: User space buffer length.
463c848434cSLee Jones * @off: Buffer offset.
4640443b3f4SQuentin Deslandes *
4650443b3f4SQuentin Deslandes * As defined by the device's documentation, we need to write to the device's
4660443b3f4SQuentin Deslandes * data buffer then to the device's packet length register atomically. Also,
4670443b3f4SQuentin Deslandes * we need to lock before checking if the device has available space to avoid
4680443b3f4SQuentin Deslandes * any concurrency issue.
4690443b3f4SQuentin Deslandes *
4700443b3f4SQuentin Deslandes * Returns the number of bytes written to the device or negative error code
4710443b3f4SQuentin Deslandes * on failure.
4720443b3f4SQuentin Deslandes */
axis_fifo_write(struct file * f,const char __user * buf,size_t len,loff_t * off)4734a965c5fSJacob Feder static ssize_t axis_fifo_write(struct file *f, const char __user *buf,
4744a965c5fSJacob Feder size_t len, loff_t *off)
4754a965c5fSJacob Feder {
4764a965c5fSJacob Feder struct axis_fifo *fifo = (struct axis_fifo *)f->private_data;
4774a965c5fSJacob Feder unsigned int words_to_write;
4784a965c5fSJacob Feder unsigned int copied;
4794a965c5fSJacob Feder unsigned int copy;
4804a965c5fSJacob Feder unsigned int i;
4814a965c5fSJacob Feder int ret;
4824a965c5fSJacob Feder u32 tmp_buf[WRITE_BUF_SIZE];
4834a965c5fSJacob Feder
4844a965c5fSJacob Feder if (len % sizeof(u32)) {
4854a965c5fSJacob Feder dev_err(fifo->dt_device,
4864a965c5fSJacob Feder "tried to send a packet that isn't word-aligned\n");
4874a965c5fSJacob Feder return -EINVAL;
4884a965c5fSJacob Feder }
4894a965c5fSJacob Feder
4904a965c5fSJacob Feder words_to_write = len / sizeof(u32);
4914a965c5fSJacob Feder
4924a965c5fSJacob Feder if (!words_to_write) {
4934a965c5fSJacob Feder dev_err(fifo->dt_device,
4944a965c5fSJacob Feder "tried to send a packet of length 0\n");
4954a965c5fSJacob Feder return -EINVAL;
4964a965c5fSJacob Feder }
4974a965c5fSJacob Feder
4984a965c5fSJacob Feder if (words_to_write > fifo->tx_fifo_depth) {
4994a965c5fSJacob Feder dev_err(fifo->dt_device, "tried to write more words [%u] than slots in the fifo buffer [%u]\n",
5004a965c5fSJacob Feder words_to_write, fifo->tx_fifo_depth);
5014a965c5fSJacob Feder return -EINVAL;
5024a965c5fSJacob Feder }
5034a965c5fSJacob Feder
5044a965c5fSJacob Feder if (fifo->write_flags & O_NONBLOCK) {
5050443b3f4SQuentin Deslandes /*
5060443b3f4SQuentin Deslandes * Device opened in non-blocking mode. Try to lock it and then
5070443b3f4SQuentin Deslandes * check if there is any room to write the given buffer.
5084a965c5fSJacob Feder */
5090443b3f4SQuentin Deslandes if (!mutex_trylock(&fifo->write_lock))
5100443b3f4SQuentin Deslandes return -EAGAIN;
5110443b3f4SQuentin Deslandes
5124a965c5fSJacob Feder if (words_to_write > ioread32(fifo->base_addr +
5134a965c5fSJacob Feder XLLF_TDFV_OFFSET)) {
5140443b3f4SQuentin Deslandes ret = -EAGAIN;
5150443b3f4SQuentin Deslandes goto end_unlock;
5164a965c5fSJacob Feder }
5174a965c5fSJacob Feder } else {
5184a965c5fSJacob Feder /* opened in blocking mode */
5194a965c5fSJacob Feder
5204a965c5fSJacob Feder /* wait for an interrupt (or timeout) if there isn't
5214a965c5fSJacob Feder * currently enough room in the fifo
5224a965c5fSJacob Feder */
5230443b3f4SQuentin Deslandes mutex_lock(&fifo->write_lock);
5240443b3f4SQuentin Deslandes ret = wait_event_interruptible_timeout(fifo->write_queue,
5254a965c5fSJacob Feder ioread32(fifo->base_addr + XLLF_TDFV_OFFSET)
5264a965c5fSJacob Feder >= words_to_write,
527752cbd8fSKhadija Kamran write_timeout);
5284a965c5fSJacob Feder
5290443b3f4SQuentin Deslandes if (ret <= 0) {
5304a965c5fSJacob Feder if (ret == 0) {
5310443b3f4SQuentin Deslandes ret = -EAGAIN;
5320443b3f4SQuentin Deslandes } else if (ret != -ERESTARTSYS) {
5330443b3f4SQuentin Deslandes dev_err(fifo->dt_device, "wait_event_interruptible_timeout() error in write (ret=%i)\n",
5344a965c5fSJacob Feder ret);
5350443b3f4SQuentin Deslandes }
5360443b3f4SQuentin Deslandes
5370443b3f4SQuentin Deslandes goto end_unlock;
5384a965c5fSJacob Feder }
5394a965c5fSJacob Feder }
5404a965c5fSJacob Feder
5414a965c5fSJacob Feder /* write data from an intermediate buffer into the fifo IP, refilling
5424a965c5fSJacob Feder * the buffer with userspace data as needed
5434a965c5fSJacob Feder */
5444a965c5fSJacob Feder copied = 0;
5454a965c5fSJacob Feder while (words_to_write > 0) {
5464a965c5fSJacob Feder copy = min(words_to_write, WRITE_BUF_SIZE);
5474a965c5fSJacob Feder
5484a965c5fSJacob Feder if (copy_from_user(tmp_buf, buf + copied * sizeof(u32),
5494a965c5fSJacob Feder copy * sizeof(u32))) {
5504a965c5fSJacob Feder reset_ip_core(fifo);
5510443b3f4SQuentin Deslandes ret = -EFAULT;
5520443b3f4SQuentin Deslandes goto end_unlock;
5534a965c5fSJacob Feder }
5544a965c5fSJacob Feder
5554a965c5fSJacob Feder for (i = 0; i < copy; i++)
5564a965c5fSJacob Feder iowrite32(tmp_buf[i], fifo->base_addr +
5574a965c5fSJacob Feder XLLF_TDFD_OFFSET);
5584a965c5fSJacob Feder
5594a965c5fSJacob Feder copied += copy;
5604a965c5fSJacob Feder words_to_write -= copy;
5614a965c5fSJacob Feder }
5624a965c5fSJacob Feder
5630443b3f4SQuentin Deslandes ret = copied * sizeof(u32);
5644a965c5fSJacob Feder
5650443b3f4SQuentin Deslandes /* write packet size to fifo */
5660443b3f4SQuentin Deslandes iowrite32(ret, fifo->base_addr + XLLF_TLR_OFFSET);
5670443b3f4SQuentin Deslandes
5680443b3f4SQuentin Deslandes end_unlock:
5690443b3f4SQuentin Deslandes mutex_unlock(&fifo->write_lock);
5700443b3f4SQuentin Deslandes
5710443b3f4SQuentin Deslandes return ret;
5724a965c5fSJacob Feder }
5734a965c5fSJacob Feder
axis_fifo_irq(int irq,void * dw)5744a965c5fSJacob Feder static irqreturn_t axis_fifo_irq(int irq, void *dw)
5754a965c5fSJacob Feder {
5764a965c5fSJacob Feder struct axis_fifo *fifo = (struct axis_fifo *)dw;
5774a965c5fSJacob Feder unsigned int pending_interrupts;
5784a965c5fSJacob Feder
5794a965c5fSJacob Feder do {
5804a965c5fSJacob Feder pending_interrupts = ioread32(fifo->base_addr +
5814a965c5fSJacob Feder XLLF_IER_OFFSET) &
5824a965c5fSJacob Feder ioread32(fifo->base_addr
5834a965c5fSJacob Feder + XLLF_ISR_OFFSET);
5844a965c5fSJacob Feder if (pending_interrupts & XLLF_INT_RC_MASK) {
5854a965c5fSJacob Feder /* packet received */
5864a965c5fSJacob Feder
5874a965c5fSJacob Feder /* wake the reader process if it is waiting */
5884a965c5fSJacob Feder wake_up(&fifo->read_queue);
5894a965c5fSJacob Feder
5904a965c5fSJacob Feder /* clear interrupt */
5914a965c5fSJacob Feder iowrite32(XLLF_INT_RC_MASK & XLLF_INT_ALL_MASK,
5924a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
5934a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TC_MASK) {
5944a965c5fSJacob Feder /* packet sent */
5954a965c5fSJacob Feder
5964a965c5fSJacob Feder /* wake the writer process if it is waiting */
5974a965c5fSJacob Feder wake_up(&fifo->write_queue);
5984a965c5fSJacob Feder
5994a965c5fSJacob Feder iowrite32(XLLF_INT_TC_MASK & XLLF_INT_ALL_MASK,
6004a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6014a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TFPF_MASK) {
6024a965c5fSJacob Feder /* transmit fifo programmable full */
6034a965c5fSJacob Feder
6044a965c5fSJacob Feder iowrite32(XLLF_INT_TFPF_MASK & XLLF_INT_ALL_MASK,
6054a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6064a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TFPE_MASK) {
6074a965c5fSJacob Feder /* transmit fifo programmable empty */
6084a965c5fSJacob Feder
6094a965c5fSJacob Feder iowrite32(XLLF_INT_TFPE_MASK & XLLF_INT_ALL_MASK,
6104a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6114a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RFPF_MASK) {
6124a965c5fSJacob Feder /* receive fifo programmable full */
6134a965c5fSJacob Feder
6144a965c5fSJacob Feder iowrite32(XLLF_INT_RFPF_MASK & XLLF_INT_ALL_MASK,
6154a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6164a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RFPE_MASK) {
6174a965c5fSJacob Feder /* receive fifo programmable empty */
6184a965c5fSJacob Feder
6194a965c5fSJacob Feder iowrite32(XLLF_INT_RFPE_MASK & XLLF_INT_ALL_MASK,
6204a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6214a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TRC_MASK) {
6224a965c5fSJacob Feder /* transmit reset complete interrupt */
6234a965c5fSJacob Feder
6244a965c5fSJacob Feder iowrite32(XLLF_INT_TRC_MASK & XLLF_INT_ALL_MASK,
6254a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6264a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RRC_MASK) {
6274a965c5fSJacob Feder /* receive reset complete interrupt */
6284a965c5fSJacob Feder
6294a965c5fSJacob Feder iowrite32(XLLF_INT_RRC_MASK & XLLF_INT_ALL_MASK,
6304a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6314a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RPURE_MASK) {
6324a965c5fSJacob Feder /* receive fifo under-read error interrupt */
6334a965c5fSJacob Feder dev_err(fifo->dt_device,
6344a965c5fSJacob Feder "receive under-read interrupt\n");
6354a965c5fSJacob Feder
6364a965c5fSJacob Feder iowrite32(XLLF_INT_RPURE_MASK & XLLF_INT_ALL_MASK,
6374a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6384a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RPORE_MASK) {
6394a965c5fSJacob Feder /* receive over-read error interrupt */
6404a965c5fSJacob Feder dev_err(fifo->dt_device,
6414a965c5fSJacob Feder "receive over-read interrupt\n");
6424a965c5fSJacob Feder
6434a965c5fSJacob Feder iowrite32(XLLF_INT_RPORE_MASK & XLLF_INT_ALL_MASK,
6444a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6454a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_RPUE_MASK) {
6464a965c5fSJacob Feder /* receive underrun error interrupt */
6474a965c5fSJacob Feder dev_err(fifo->dt_device,
6484a965c5fSJacob Feder "receive underrun error interrupt\n");
6494a965c5fSJacob Feder
6504a965c5fSJacob Feder iowrite32(XLLF_INT_RPUE_MASK & XLLF_INT_ALL_MASK,
6514a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6524a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TPOE_MASK) {
6534a965c5fSJacob Feder /* transmit overrun error interrupt */
6544a965c5fSJacob Feder dev_err(fifo->dt_device,
6554a965c5fSJacob Feder "transmit overrun error interrupt\n");
6564a965c5fSJacob Feder
6574a965c5fSJacob Feder iowrite32(XLLF_INT_TPOE_MASK & XLLF_INT_ALL_MASK,
6584a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6594a965c5fSJacob Feder } else if (pending_interrupts & XLLF_INT_TSE_MASK) {
6604a965c5fSJacob Feder /* transmit length mismatch error interrupt */
6614a965c5fSJacob Feder dev_err(fifo->dt_device,
6624a965c5fSJacob Feder "transmit length mismatch error interrupt\n");
6634a965c5fSJacob Feder
6644a965c5fSJacob Feder iowrite32(XLLF_INT_TSE_MASK & XLLF_INT_ALL_MASK,
6654a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6664a965c5fSJacob Feder } else if (pending_interrupts) {
6674a965c5fSJacob Feder /* unknown interrupt type */
6684a965c5fSJacob Feder dev_err(fifo->dt_device,
6694a965c5fSJacob Feder "unknown interrupt(s) 0x%x\n",
6704a965c5fSJacob Feder pending_interrupts);
6714a965c5fSJacob Feder
6724a965c5fSJacob Feder iowrite32(XLLF_INT_ALL_MASK,
6734a965c5fSJacob Feder fifo->base_addr + XLLF_ISR_OFFSET);
6744a965c5fSJacob Feder }
6754a965c5fSJacob Feder } while (pending_interrupts);
6764a965c5fSJacob Feder
6774a965c5fSJacob Feder return IRQ_HANDLED;
6784a965c5fSJacob Feder }
6794a965c5fSJacob Feder
axis_fifo_open(struct inode * inod,struct file * f)6804a965c5fSJacob Feder static int axis_fifo_open(struct inode *inod, struct file *f)
6814a965c5fSJacob Feder {
682d2d7aa53SGreg Kroah-Hartman struct axis_fifo *fifo = container_of(f->private_data,
683d2d7aa53SGreg Kroah-Hartman struct axis_fifo, miscdev);
6844a965c5fSJacob Feder f->private_data = fifo;
6854a965c5fSJacob Feder
6864a965c5fSJacob Feder if (((f->f_flags & O_ACCMODE) == O_WRONLY) ||
6874a965c5fSJacob Feder ((f->f_flags & O_ACCMODE) == O_RDWR)) {
6884a965c5fSJacob Feder if (fifo->has_tx_fifo) {
6894a965c5fSJacob Feder fifo->write_flags = f->f_flags;
6904a965c5fSJacob Feder } else {
6914a965c5fSJacob Feder dev_err(fifo->dt_device, "tried to open device for write but the transmit fifo is disabled\n");
6924a965c5fSJacob Feder return -EPERM;
6934a965c5fSJacob Feder }
6944a965c5fSJacob Feder }
6954a965c5fSJacob Feder
6964a965c5fSJacob Feder if (((f->f_flags & O_ACCMODE) == O_RDONLY) ||
6974a965c5fSJacob Feder ((f->f_flags & O_ACCMODE) == O_RDWR)) {
6984a965c5fSJacob Feder if (fifo->has_rx_fifo) {
6994a965c5fSJacob Feder fifo->read_flags = f->f_flags;
7004a965c5fSJacob Feder } else {
7014a965c5fSJacob Feder dev_err(fifo->dt_device, "tried to open device for read but the receive fifo is disabled\n");
7024a965c5fSJacob Feder return -EPERM;
7034a965c5fSJacob Feder }
7044a965c5fSJacob Feder }
7054a965c5fSJacob Feder
7064a965c5fSJacob Feder return 0;
7074a965c5fSJacob Feder }
7084a965c5fSJacob Feder
axis_fifo_close(struct inode * inod,struct file * f)7094a965c5fSJacob Feder static int axis_fifo_close(struct inode *inod, struct file *f)
7104a965c5fSJacob Feder {
7114a965c5fSJacob Feder f->private_data = NULL;
7124a965c5fSJacob Feder
7134a965c5fSJacob Feder return 0;
7144a965c5fSJacob Feder }
7154a965c5fSJacob Feder
7164a965c5fSJacob Feder static const struct file_operations fops = {
7174a965c5fSJacob Feder .owner = THIS_MODULE,
7184a965c5fSJacob Feder .open = axis_fifo_open,
7194a965c5fSJacob Feder .release = axis_fifo_close,
7204a965c5fSJacob Feder .read = axis_fifo_read,
7214a965c5fSJacob Feder .write = axis_fifo_write
7224a965c5fSJacob Feder };
7234a965c5fSJacob Feder
7244a965c5fSJacob Feder /* read named property from the device tree */
get_dts_property(struct axis_fifo * fifo,char * name,unsigned int * var)7254a965c5fSJacob Feder static int get_dts_property(struct axis_fifo *fifo,
7264a965c5fSJacob Feder char *name, unsigned int *var)
7274a965c5fSJacob Feder {
7284a965c5fSJacob Feder int rc;
7294a965c5fSJacob Feder
7304a965c5fSJacob Feder rc = of_property_read_u32(fifo->dt_device->of_node, name, var);
7314a965c5fSJacob Feder if (rc) {
7324a965c5fSJacob Feder dev_err(fifo->dt_device, "couldn't read IP dts property '%s'",
7334a965c5fSJacob Feder name);
7344a965c5fSJacob Feder return rc;
7354a965c5fSJacob Feder }
7364a965c5fSJacob Feder dev_dbg(fifo->dt_device, "dts property '%s' = %u\n",
7374a965c5fSJacob Feder name, *var);
7384a965c5fSJacob Feder
7394a965c5fSJacob Feder return 0;
7404a965c5fSJacob Feder }
7414a965c5fSJacob Feder
axis_fifo_parse_dt(struct axis_fifo * fifo)742ed6daf2bSQuentin Deslandes static int axis_fifo_parse_dt(struct axis_fifo *fifo)
743ed6daf2bSQuentin Deslandes {
744ed6daf2bSQuentin Deslandes int ret;
745ed6daf2bSQuentin Deslandes unsigned int value;
746ed6daf2bSQuentin Deslandes
747ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,axi-str-rxd-tdata-width", &value);
748ed6daf2bSQuentin Deslandes if (ret) {
749ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,axi-str-rxd-tdata-width property\n");
750ed6daf2bSQuentin Deslandes goto end;
751ed6daf2bSQuentin Deslandes } else if (value != 32) {
752ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "xlnx,axi-str-rxd-tdata-width only supports 32 bits\n");
753ed6daf2bSQuentin Deslandes ret = -EIO;
754ed6daf2bSQuentin Deslandes goto end;
755ed6daf2bSQuentin Deslandes }
756ed6daf2bSQuentin Deslandes
757ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,axi-str-txd-tdata-width", &value);
758ed6daf2bSQuentin Deslandes if (ret) {
759ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,axi-str-txd-tdata-width property\n");
760ed6daf2bSQuentin Deslandes goto end;
761ed6daf2bSQuentin Deslandes } else if (value != 32) {
762ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "xlnx,axi-str-txd-tdata-width only supports 32 bits\n");
763ed6daf2bSQuentin Deslandes ret = -EIO;
764ed6daf2bSQuentin Deslandes goto end;
765ed6daf2bSQuentin Deslandes }
766ed6daf2bSQuentin Deslandes
767ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,rx-fifo-depth",
768ed6daf2bSQuentin Deslandes &fifo->rx_fifo_depth);
769ed6daf2bSQuentin Deslandes if (ret) {
770ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,rx-fifo-depth property\n");
771ed6daf2bSQuentin Deslandes ret = -EIO;
772ed6daf2bSQuentin Deslandes goto end;
773ed6daf2bSQuentin Deslandes }
774ed6daf2bSQuentin Deslandes
775ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,tx-fifo-depth",
776ed6daf2bSQuentin Deslandes &fifo->tx_fifo_depth);
777ed6daf2bSQuentin Deslandes if (ret) {
778ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,tx-fifo-depth property\n");
779ed6daf2bSQuentin Deslandes ret = -EIO;
780ed6daf2bSQuentin Deslandes goto end;
781ed6daf2bSQuentin Deslandes }
782ed6daf2bSQuentin Deslandes
783ed6daf2bSQuentin Deslandes /* IP sets TDFV to fifo depth - 4 so we will do the same */
784ed6daf2bSQuentin Deslandes fifo->tx_fifo_depth -= 4;
785ed6daf2bSQuentin Deslandes
786ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,use-rx-data", &fifo->has_rx_fifo);
787ed6daf2bSQuentin Deslandes if (ret) {
788ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,use-rx-data property\n");
789ed6daf2bSQuentin Deslandes ret = -EIO;
790ed6daf2bSQuentin Deslandes goto end;
791ed6daf2bSQuentin Deslandes }
792ed6daf2bSQuentin Deslandes
793ed6daf2bSQuentin Deslandes ret = get_dts_property(fifo, "xlnx,use-tx-data", &fifo->has_tx_fifo);
794ed6daf2bSQuentin Deslandes if (ret) {
795ed6daf2bSQuentin Deslandes dev_err(fifo->dt_device, "missing xlnx,use-tx-data property\n");
796ed6daf2bSQuentin Deslandes ret = -EIO;
797ed6daf2bSQuentin Deslandes goto end;
798ed6daf2bSQuentin Deslandes }
799ed6daf2bSQuentin Deslandes
800ed6daf2bSQuentin Deslandes end:
801ed6daf2bSQuentin Deslandes return ret;
802ed6daf2bSQuentin Deslandes }
803ed6daf2bSQuentin Deslandes
axis_fifo_probe(struct platform_device * pdev)8044a965c5fSJacob Feder static int axis_fifo_probe(struct platform_device *pdev)
8054a965c5fSJacob Feder {
8064a965c5fSJacob Feder struct resource *r_mem; /* IO mem resources */
8074a965c5fSJacob Feder struct device *dev = &pdev->dev; /* OS device (from device tree) */
8084a965c5fSJacob Feder struct axis_fifo *fifo = NULL;
809d2d7aa53SGreg Kroah-Hartman char *device_name;
8104a965c5fSJacob Feder int rc = 0; /* error return value */
8114a965c5fSJacob Feder
8124a965c5fSJacob Feder /* ----------------------------
8134a965c5fSJacob Feder * init wrapper device
8144a965c5fSJacob Feder * ----------------------------
8154a965c5fSJacob Feder */
8164a965c5fSJacob Feder
817d2d7aa53SGreg Kroah-Hartman device_name = devm_kzalloc(dev, 32, GFP_KERNEL);
818d2d7aa53SGreg Kroah-Hartman if (!device_name)
819d2d7aa53SGreg Kroah-Hartman return -ENOMEM;
820d2d7aa53SGreg Kroah-Hartman
8214a965c5fSJacob Feder /* allocate device wrapper memory */
822d2d7aa53SGreg Kroah-Hartman fifo = devm_kzalloc(dev, sizeof(*fifo), GFP_KERNEL);
8234a965c5fSJacob Feder if (!fifo)
8244a965c5fSJacob Feder return -ENOMEM;
8254a965c5fSJacob Feder
8264a965c5fSJacob Feder dev_set_drvdata(dev, fifo);
8274a965c5fSJacob Feder fifo->dt_device = dev;
8284a965c5fSJacob Feder
8294a965c5fSJacob Feder init_waitqueue_head(&fifo->read_queue);
8304a965c5fSJacob Feder init_waitqueue_head(&fifo->write_queue);
8314a965c5fSJacob Feder
8320443b3f4SQuentin Deslandes mutex_init(&fifo->read_lock);
8330443b3f4SQuentin Deslandes mutex_init(&fifo->write_lock);
8344a965c5fSJacob Feder
8354a965c5fSJacob Feder /* ----------------------------
8364a965c5fSJacob Feder * init device memory space
8374a965c5fSJacob Feder * ----------------------------
8384a965c5fSJacob Feder */
8394a965c5fSJacob Feder
840405f3d10SYangtao Li /* get iospace for the device and request physical memory */
841405f3d10SYangtao Li fifo->base_addr = devm_platform_get_and_ioremap_resource(pdev, 0, &r_mem);
8426a20d283SQuentin Deslandes if (IS_ERR(fifo->base_addr)) {
8436a20d283SQuentin Deslandes rc = PTR_ERR(fifo->base_addr);
8444a965c5fSJacob Feder goto err_initial;
8454a965c5fSJacob Feder }
8464a965c5fSJacob Feder
8474a965c5fSJacob Feder dev_dbg(fifo->dt_device, "remapped memory to 0x%p\n", fifo->base_addr);
8484a965c5fSJacob Feder
8494a965c5fSJacob Feder /* create unique device name */
850d2d7aa53SGreg Kroah-Hartman snprintf(device_name, 32, "%s_%pa", DRIVER_NAME, &r_mem->start);
8514a965c5fSJacob Feder dev_dbg(fifo->dt_device, "device name [%s]\n", device_name);
8524a965c5fSJacob Feder
8534a965c5fSJacob Feder /* ----------------------------
8544a965c5fSJacob Feder * init IP
8554a965c5fSJacob Feder * ----------------------------
8564a965c5fSJacob Feder */
8574a965c5fSJacob Feder
858ed6daf2bSQuentin Deslandes rc = axis_fifo_parse_dt(fifo);
8594a965c5fSJacob Feder if (rc)
8606a20d283SQuentin Deslandes goto err_initial;
8614a965c5fSJacob Feder
8624a965c5fSJacob Feder reset_ip_core(fifo);
8634a965c5fSJacob Feder
8644a965c5fSJacob Feder /* ----------------------------
8654a965c5fSJacob Feder * init device interrupts
8664a965c5fSJacob Feder * ----------------------------
8674a965c5fSJacob Feder */
8684a965c5fSJacob Feder
8694a965c5fSJacob Feder /* get IRQ resource */
870790ada0eSLad Prabhakar rc = platform_get_irq(pdev, 0);
871790ada0eSLad Prabhakar if (rc < 0)
8726a20d283SQuentin Deslandes goto err_initial;
8734a965c5fSJacob Feder
8744a965c5fSJacob Feder /* request IRQ */
875790ada0eSLad Prabhakar fifo->irq = rc;
8766a20d283SQuentin Deslandes rc = devm_request_irq(fifo->dt_device, fifo->irq, &axis_fifo_irq, 0,
8776a20d283SQuentin Deslandes DRIVER_NAME, fifo);
8784a965c5fSJacob Feder if (rc) {
8794a965c5fSJacob Feder dev_err(fifo->dt_device, "couldn't allocate interrupt %i\n",
8804a965c5fSJacob Feder fifo->irq);
8816a20d283SQuentin Deslandes goto err_initial;
8824a965c5fSJacob Feder }
8834a965c5fSJacob Feder
8844a965c5fSJacob Feder /* ----------------------------
8854a965c5fSJacob Feder * init char device
8864a965c5fSJacob Feder * ----------------------------
8874a965c5fSJacob Feder */
8884a965c5fSJacob Feder
889d2d7aa53SGreg Kroah-Hartman /* create character device */
890d2d7aa53SGreg Kroah-Hartman fifo->miscdev.fops = &fops;
891d2d7aa53SGreg Kroah-Hartman fifo->miscdev.minor = MISC_DYNAMIC_MINOR;
892d2d7aa53SGreg Kroah-Hartman fifo->miscdev.name = device_name;
893d2d7aa53SGreg Kroah-Hartman fifo->miscdev.groups = axis_fifo_attrs_groups;
894d2d7aa53SGreg Kroah-Hartman fifo->miscdev.parent = dev;
895d2d7aa53SGreg Kroah-Hartman rc = misc_register(&fifo->miscdev);
8964a965c5fSJacob Feder if (rc < 0)
8976a20d283SQuentin Deslandes goto err_initial;
8984a965c5fSJacob Feder
8994a965c5fSJacob Feder return 0;
9004a965c5fSJacob Feder
9014a965c5fSJacob Feder err_initial:
9024a965c5fSJacob Feder dev_set_drvdata(dev, NULL);
9034a965c5fSJacob Feder return rc;
9044a965c5fSJacob Feder }
9054a965c5fSJacob Feder
axis_fifo_remove(struct platform_device * pdev)90663b2af49SUwe Kleine-König static void axis_fifo_remove(struct platform_device *pdev)
9074a965c5fSJacob Feder {
9084a965c5fSJacob Feder struct device *dev = &pdev->dev;
9094a965c5fSJacob Feder struct axis_fifo *fifo = dev_get_drvdata(dev);
9104a965c5fSJacob Feder
911d2d7aa53SGreg Kroah-Hartman misc_deregister(&fifo->miscdev);
9124a965c5fSJacob Feder dev_set_drvdata(dev, NULL);
9134a965c5fSJacob Feder }
9144a965c5fSJacob Feder
9154a965c5fSJacob Feder static const struct of_device_id axis_fifo_of_match[] = {
9164a965c5fSJacob Feder { .compatible = "xlnx,axi-fifo-mm-s-4.1", },
9174a965c5fSJacob Feder {},
9184a965c5fSJacob Feder };
9194a965c5fSJacob Feder MODULE_DEVICE_TABLE(of, axis_fifo_of_match);
9204a965c5fSJacob Feder
9214a965c5fSJacob Feder static struct platform_driver axis_fifo_driver = {
9224a965c5fSJacob Feder .driver = {
9234a965c5fSJacob Feder .name = DRIVER_NAME,
9244a965c5fSJacob Feder .of_match_table = axis_fifo_of_match,
9254a965c5fSJacob Feder },
9264a965c5fSJacob Feder .probe = axis_fifo_probe,
92763b2af49SUwe Kleine-König .remove_new = axis_fifo_remove,
9284a965c5fSJacob Feder };
9294a965c5fSJacob Feder
axis_fifo_init(void)9304a965c5fSJacob Feder static int __init axis_fifo_init(void)
9314a965c5fSJacob Feder {
932752cbd8fSKhadija Kamran if (read_timeout >= 0)
933752cbd8fSKhadija Kamran read_timeout = msecs_to_jiffies(read_timeout);
934752cbd8fSKhadija Kamran else
935752cbd8fSKhadija Kamran read_timeout = MAX_SCHEDULE_TIMEOUT;
936752cbd8fSKhadija Kamran
937752cbd8fSKhadija Kamran if (write_timeout >= 0)
938752cbd8fSKhadija Kamran write_timeout = msecs_to_jiffies(write_timeout);
939752cbd8fSKhadija Kamran else
940752cbd8fSKhadija Kamran write_timeout = MAX_SCHEDULE_TIMEOUT;
941752cbd8fSKhadija Kamran
942752cbd8fSKhadija Kamran pr_info("axis-fifo driver loaded with parameters read_timeout = %li, write_timeout = %li\n",
9434a965c5fSJacob Feder read_timeout, write_timeout);
9444a965c5fSJacob Feder return platform_driver_register(&axis_fifo_driver);
9454a965c5fSJacob Feder }
9464a965c5fSJacob Feder
9474a965c5fSJacob Feder module_init(axis_fifo_init);
9484a965c5fSJacob Feder
axis_fifo_exit(void)9494a965c5fSJacob Feder static void __exit axis_fifo_exit(void)
9504a965c5fSJacob Feder {
9514a965c5fSJacob Feder platform_driver_unregister(&axis_fifo_driver);
9524a965c5fSJacob Feder }
9534a965c5fSJacob Feder
9544a965c5fSJacob Feder module_exit(axis_fifo_exit);
9554a965c5fSJacob Feder
9564a965c5fSJacob Feder MODULE_LICENSE("GPL");
9574a965c5fSJacob Feder MODULE_AUTHOR("Jacob Feder <jacobsfeder@gmail.com>");
9584a965c5fSJacob Feder MODULE_DESCRIPTION("Xilinx AXI-Stream FIFO v4.1 IP core driver");
959