640 lines
17 KiB
C
640 lines
17 KiB
C
/*
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* DMA Engine test module
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*
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* Copyright (C) 2007 Atmel Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/delay.h>
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#include <linux/dma-mapping.h>
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#include <linux/dmaengine.h>
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#include <linux/init.h>
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#include <linux/kthread.h>
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/random.h>
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#include <linux/slab.h>
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#include <linux/wait.h>
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static unsigned int test_buf_size = 16384;
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module_param(test_buf_size, uint, S_IRUGO);
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MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
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static char test_channel[20];
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module_param_string(channel, test_channel, sizeof(test_channel), S_IRUGO);
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MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
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static char test_device[20];
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module_param_string(device, test_device, sizeof(test_device), S_IRUGO);
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MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
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static unsigned int threads_per_chan = 1;
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module_param(threads_per_chan, uint, S_IRUGO);
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MODULE_PARM_DESC(threads_per_chan,
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"Number of threads to start per channel (default: 1)");
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static unsigned int max_channels;
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module_param(max_channels, uint, S_IRUGO);
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MODULE_PARM_DESC(max_channels,
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"Maximum number of channels to use (default: all)");
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static unsigned int iterations;
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module_param(iterations, uint, S_IRUGO);
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MODULE_PARM_DESC(iterations,
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"Iterations before stopping test (default: infinite)");
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static unsigned int xor_sources = 3;
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module_param(xor_sources, uint, S_IRUGO);
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MODULE_PARM_DESC(xor_sources,
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"Number of xor source buffers (default: 3)");
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static unsigned int pq_sources = 3;
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module_param(pq_sources, uint, S_IRUGO);
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MODULE_PARM_DESC(pq_sources,
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"Number of p+q source buffers (default: 3)");
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static int timeout = 3000;
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module_param(timeout, uint, S_IRUGO);
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MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
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"Pass -1 for infinite timeout");
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/*
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* Initialization patterns. All bytes in the source buffer has bit 7
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* set, all bytes in the destination buffer has bit 7 cleared.
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*
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* Bit 6 is set for all bytes which are to be copied by the DMA
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* engine. Bit 5 is set for all bytes which are to be overwritten by
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* the DMA engine.
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*
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* The remaining bits are the inverse of a counter which increments by
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* one for each byte address.
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*/
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#define PATTERN_SRC 0x80
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#define PATTERN_DST 0x00
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#define PATTERN_COPY 0x40
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#define PATTERN_OVERWRITE 0x20
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#define PATTERN_COUNT_MASK 0x1f
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struct dmatest_thread {
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struct list_head node;
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struct task_struct *task;
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struct dma_chan *chan;
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u8 **srcs;
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u8 **dsts;
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enum dma_transaction_type type;
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};
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struct dmatest_chan {
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struct list_head node;
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struct dma_chan *chan;
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struct list_head threads;
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};
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/*
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* These are protected by dma_list_mutex since they're only used by
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* the DMA filter function callback
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*/
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static LIST_HEAD(dmatest_channels);
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static unsigned int nr_channels;
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static bool dmatest_match_channel(struct dma_chan *chan)
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{
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if (test_channel[0] == '\0')
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return true;
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return strcmp(dma_chan_name(chan), test_channel) == 0;
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}
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static bool dmatest_match_device(struct dma_device *device)
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{
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if (test_device[0] == '\0')
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return true;
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return strcmp(dev_name(device->dev), test_device) == 0;
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}
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static unsigned long dmatest_random(void)
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{
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unsigned long buf;
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get_random_bytes(&buf, sizeof(buf));
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return buf;
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}
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static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len)
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{
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unsigned int i;
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u8 *buf;
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for (; (buf = *bufs); bufs++) {
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for (i = 0; i < start; i++)
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buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
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for ( ; i < start + len; i++)
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buf[i] = PATTERN_SRC | PATTERN_COPY
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| (~i & PATTERN_COUNT_MASK);
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for ( ; i < test_buf_size; i++)
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buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
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buf++;
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}
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}
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static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len)
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{
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unsigned int i;
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u8 *buf;
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for (; (buf = *bufs); bufs++) {
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for (i = 0; i < start; i++)
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buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
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for ( ; i < start + len; i++)
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buf[i] = PATTERN_DST | PATTERN_OVERWRITE
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| (~i & PATTERN_COUNT_MASK);
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for ( ; i < test_buf_size; i++)
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buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
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}
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}
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static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
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unsigned int counter, bool is_srcbuf)
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{
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u8 diff = actual ^ pattern;
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u8 expected = pattern | (~counter & PATTERN_COUNT_MASK);
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const char *thread_name = current->comm;
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if (is_srcbuf)
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pr_warning("%s: srcbuf[0x%x] overwritten!"
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" Expected %02x, got %02x\n",
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thread_name, index, expected, actual);
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else if ((pattern & PATTERN_COPY)
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&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
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pr_warning("%s: dstbuf[0x%x] not copied!"
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" Expected %02x, got %02x\n",
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thread_name, index, expected, actual);
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else if (diff & PATTERN_SRC)
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pr_warning("%s: dstbuf[0x%x] was copied!"
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" Expected %02x, got %02x\n",
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thread_name, index, expected, actual);
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else
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pr_warning("%s: dstbuf[0x%x] mismatch!"
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" Expected %02x, got %02x\n",
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thread_name, index, expected, actual);
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}
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static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
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unsigned int end, unsigned int counter, u8 pattern,
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bool is_srcbuf)
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{
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unsigned int i;
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unsigned int error_count = 0;
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u8 actual;
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u8 expected;
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u8 *buf;
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unsigned int counter_orig = counter;
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for (; (buf = *bufs); bufs++) {
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counter = counter_orig;
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for (i = start; i < end; i++) {
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actual = buf[i];
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expected = pattern | (~counter & PATTERN_COUNT_MASK);
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if (actual != expected) {
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if (error_count < 32)
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dmatest_mismatch(actual, pattern, i,
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counter, is_srcbuf);
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error_count++;
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}
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counter++;
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}
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}
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if (error_count > 32)
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pr_warning("%s: %u errors suppressed\n",
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current->comm, error_count - 32);
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return error_count;
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}
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static void dmatest_callback(void *completion)
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{
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complete(completion);
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}
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/*
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* This function repeatedly tests DMA transfers of various lengths and
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* offsets for a given operation type until it is told to exit by
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* kthread_stop(). There may be multiple threads running this function
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* in parallel for a single channel, and there may be multiple channels
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* being tested in parallel.
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*
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* Before each test, the source and destination buffer is initialized
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* with a known pattern. This pattern is different depending on
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* whether it's in an area which is supposed to be copied or
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* overwritten, and different in the source and destination buffers.
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* So if the DMA engine doesn't copy exactly what we tell it to copy,
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* we'll notice.
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*/
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static int dmatest_func(void *data)
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{
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struct dmatest_thread *thread = data;
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struct dma_chan *chan;
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const char *thread_name;
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unsigned int src_off, dst_off, len;
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unsigned int error_count;
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unsigned int failed_tests = 0;
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unsigned int total_tests = 0;
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dma_cookie_t cookie;
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enum dma_status status;
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enum dma_ctrl_flags flags;
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u8 pq_coefs[pq_sources + 1];
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int ret;
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int src_cnt;
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int dst_cnt;
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int i;
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thread_name = current->comm;
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ret = -ENOMEM;
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smp_rmb();
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chan = thread->chan;
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if (thread->type == DMA_MEMCPY)
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src_cnt = dst_cnt = 1;
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else if (thread->type == DMA_XOR) {
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src_cnt = xor_sources | 1; /* force odd to ensure dst = src */
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dst_cnt = 1;
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} else if (thread->type == DMA_PQ) {
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src_cnt = pq_sources | 1; /* force odd to ensure dst = src */
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dst_cnt = 2;
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for (i = 0; i < src_cnt; i++)
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pq_coefs[i] = 1;
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} else
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goto err_srcs;
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thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
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if (!thread->srcs)
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goto err_srcs;
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for (i = 0; i < src_cnt; i++) {
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thread->srcs[i] = kmalloc(test_buf_size, GFP_KERNEL);
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if (!thread->srcs[i])
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goto err_srcbuf;
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}
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thread->srcs[i] = NULL;
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thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
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if (!thread->dsts)
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goto err_dsts;
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for (i = 0; i < dst_cnt; i++) {
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thread->dsts[i] = kmalloc(test_buf_size, GFP_KERNEL);
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if (!thread->dsts[i])
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goto err_dstbuf;
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}
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thread->dsts[i] = NULL;
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set_user_nice(current, 10);
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/*
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* src buffers are freed by the DMAEngine code with dma_unmap_single()
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* dst buffers are freed by ourselves below
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*/
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flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT
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| DMA_COMPL_SKIP_DEST_UNMAP | DMA_COMPL_SRC_UNMAP_SINGLE;
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while (!kthread_should_stop()
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&& !(iterations && total_tests >= iterations)) {
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struct dma_device *dev = chan->device;
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struct dma_async_tx_descriptor *tx = NULL;
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dma_addr_t dma_srcs[src_cnt];
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dma_addr_t dma_dsts[dst_cnt];
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struct completion cmp;
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unsigned long tmo = msecs_to_jiffies(timeout);
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u8 align = 0;
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total_tests++;
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/* honor alignment restrictions */
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if (thread->type == DMA_MEMCPY)
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align = dev->copy_align;
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else if (thread->type == DMA_XOR)
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align = dev->xor_align;
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else if (thread->type == DMA_PQ)
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align = dev->pq_align;
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if (1 << align > test_buf_size) {
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pr_err("%u-byte buffer too small for %d-byte alignment\n",
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test_buf_size, 1 << align);
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break;
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}
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len = dmatest_random() % test_buf_size + 1;
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len = (len >> align) << align;
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if (!len)
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len = 1 << align;
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src_off = dmatest_random() % (test_buf_size - len + 1);
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dst_off = dmatest_random() % (test_buf_size - len + 1);
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src_off = (src_off >> align) << align;
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dst_off = (dst_off >> align) << align;
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dmatest_init_srcs(thread->srcs, src_off, len);
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dmatest_init_dsts(thread->dsts, dst_off, len);
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for (i = 0; i < src_cnt; i++) {
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u8 *buf = thread->srcs[i] + src_off;
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dma_srcs[i] = dma_map_single(dev->dev, buf, len,
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DMA_TO_DEVICE);
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}
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/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
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for (i = 0; i < dst_cnt; i++) {
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dma_dsts[i] = dma_map_single(dev->dev, thread->dsts[i],
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test_buf_size,
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DMA_BIDIRECTIONAL);
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}
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if (thread->type == DMA_MEMCPY)
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tx = dev->device_prep_dma_memcpy(chan,
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dma_dsts[0] + dst_off,
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dma_srcs[0], len,
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flags);
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else if (thread->type == DMA_XOR)
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tx = dev->device_prep_dma_xor(chan,
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dma_dsts[0] + dst_off,
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dma_srcs, src_cnt,
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len, flags);
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else if (thread->type == DMA_PQ) {
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dma_addr_t dma_pq[dst_cnt];
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for (i = 0; i < dst_cnt; i++)
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dma_pq[i] = dma_dsts[i] + dst_off;
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tx = dev->device_prep_dma_pq(chan, dma_pq, dma_srcs,
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src_cnt, pq_coefs,
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len, flags);
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}
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if (!tx) {
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for (i = 0; i < src_cnt; i++)
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dma_unmap_single(dev->dev, dma_srcs[i], len,
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DMA_TO_DEVICE);
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for (i = 0; i < dst_cnt; i++)
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dma_unmap_single(dev->dev, dma_dsts[i],
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test_buf_size,
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DMA_BIDIRECTIONAL);
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pr_warning("%s: #%u: prep error with src_off=0x%x "
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"dst_off=0x%x len=0x%x\n",
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thread_name, total_tests - 1,
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src_off, dst_off, len);
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msleep(100);
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failed_tests++;
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continue;
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}
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init_completion(&cmp);
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tx->callback = dmatest_callback;
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tx->callback_param = &cmp;
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cookie = tx->tx_submit(tx);
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if (dma_submit_error(cookie)) {
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pr_warning("%s: #%u: submit error %d with src_off=0x%x "
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"dst_off=0x%x len=0x%x\n",
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thread_name, total_tests - 1, cookie,
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src_off, dst_off, len);
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msleep(100);
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failed_tests++;
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continue;
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}
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dma_async_issue_pending(chan);
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tmo = wait_for_completion_timeout(&cmp, tmo);
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status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
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if (tmo == 0) {
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pr_warning("%s: #%u: test timed out\n",
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thread_name, total_tests - 1);
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failed_tests++;
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continue;
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} else if (status != DMA_SUCCESS) {
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pr_warning("%s: #%u: got completion callback,"
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" but status is \'%s\'\n",
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thread_name, total_tests - 1,
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status == DMA_ERROR ? "error" : "in progress");
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failed_tests++;
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continue;
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}
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/* Unmap by myself (see DMA_COMPL_SKIP_DEST_UNMAP above) */
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for (i = 0; i < dst_cnt; i++)
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dma_unmap_single(dev->dev, dma_dsts[i], test_buf_size,
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DMA_BIDIRECTIONAL);
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error_count = 0;
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pr_debug("%s: verifying source buffer...\n", thread_name);
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error_count += dmatest_verify(thread->srcs, 0, src_off,
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0, PATTERN_SRC, true);
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error_count += dmatest_verify(thread->srcs, src_off,
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src_off + len, src_off,
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PATTERN_SRC | PATTERN_COPY, true);
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error_count += dmatest_verify(thread->srcs, src_off + len,
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test_buf_size, src_off + len,
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PATTERN_SRC, true);
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pr_debug("%s: verifying dest buffer...\n",
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thread->task->comm);
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error_count += dmatest_verify(thread->dsts, 0, dst_off,
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0, PATTERN_DST, false);
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error_count += dmatest_verify(thread->dsts, dst_off,
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dst_off + len, src_off,
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PATTERN_SRC | PATTERN_COPY, false);
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error_count += dmatest_verify(thread->dsts, dst_off + len,
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test_buf_size, dst_off + len,
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PATTERN_DST, false);
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if (error_count) {
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pr_warning("%s: #%u: %u errors with "
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"src_off=0x%x dst_off=0x%x len=0x%x\n",
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thread_name, total_tests - 1, error_count,
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src_off, dst_off, len);
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failed_tests++;
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} else {
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pr_debug("%s: #%u: No errors with "
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"src_off=0x%x dst_off=0x%x len=0x%x\n",
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thread_name, total_tests - 1,
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src_off, dst_off, len);
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}
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}
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ret = 0;
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for (i = 0; thread->dsts[i]; i++)
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kfree(thread->dsts[i]);
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err_dstbuf:
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kfree(thread->dsts);
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err_dsts:
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for (i = 0; thread->srcs[i]; i++)
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kfree(thread->srcs[i]);
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err_srcbuf:
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kfree(thread->srcs);
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err_srcs:
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pr_notice("%s: terminating after %u tests, %u failures (status %d)\n",
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thread_name, total_tests, failed_tests, ret);
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if (iterations > 0)
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while (!kthread_should_stop()) {
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DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wait_dmatest_exit);
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interruptible_sleep_on(&wait_dmatest_exit);
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}
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return ret;
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}
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static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
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{
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struct dmatest_thread *thread;
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struct dmatest_thread *_thread;
|
|
int ret;
|
|
|
|
list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
|
|
ret = kthread_stop(thread->task);
|
|
pr_debug("dmatest: thread %s exited with status %d\n",
|
|
thread->task->comm, ret);
|
|
list_del(&thread->node);
|
|
kfree(thread);
|
|
}
|
|
kfree(dtc);
|
|
}
|
|
|
|
static int dmatest_add_threads(struct dmatest_chan *dtc, enum dma_transaction_type type)
|
|
{
|
|
struct dmatest_thread *thread;
|
|
struct dma_chan *chan = dtc->chan;
|
|
char *op;
|
|
unsigned int i;
|
|
|
|
if (type == DMA_MEMCPY)
|
|
op = "copy";
|
|
else if (type == DMA_XOR)
|
|
op = "xor";
|
|
else if (type == DMA_PQ)
|
|
op = "pq";
|
|
else
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < threads_per_chan; i++) {
|
|
thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
|
|
if (!thread) {
|
|
pr_warning("dmatest: No memory for %s-%s%u\n",
|
|
dma_chan_name(chan), op, i);
|
|
|
|
break;
|
|
}
|
|
thread->chan = dtc->chan;
|
|
thread->type = type;
|
|
smp_wmb();
|
|
thread->task = kthread_run(dmatest_func, thread, "%s-%s%u",
|
|
dma_chan_name(chan), op, i);
|
|
if (IS_ERR(thread->task)) {
|
|
pr_warning("dmatest: Failed to run thread %s-%s%u\n",
|
|
dma_chan_name(chan), op, i);
|
|
kfree(thread);
|
|
break;
|
|
}
|
|
|
|
/* srcbuf and dstbuf are allocated by the thread itself */
|
|
|
|
list_add_tail(&thread->node, &dtc->threads);
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
static int dmatest_add_channel(struct dma_chan *chan)
|
|
{
|
|
struct dmatest_chan *dtc;
|
|
struct dma_device *dma_dev = chan->device;
|
|
unsigned int thread_count = 0;
|
|
int cnt;
|
|
|
|
dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
|
|
if (!dtc) {
|
|
pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan));
|
|
return -ENOMEM;
|
|
}
|
|
|
|
dtc->chan = chan;
|
|
INIT_LIST_HEAD(&dtc->threads);
|
|
|
|
if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
|
|
cnt = dmatest_add_threads(dtc, DMA_MEMCPY);
|
|
thread_count += cnt > 0 ? cnt : 0;
|
|
}
|
|
if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
|
|
cnt = dmatest_add_threads(dtc, DMA_XOR);
|
|
thread_count += cnt > 0 ? cnt : 0;
|
|
}
|
|
if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
|
|
cnt = dmatest_add_threads(dtc, DMA_PQ);
|
|
thread_count += cnt > 0 ?: 0;
|
|
}
|
|
|
|
pr_info("dmatest: Started %u threads using %s\n",
|
|
thread_count, dma_chan_name(chan));
|
|
|
|
list_add_tail(&dtc->node, &dmatest_channels);
|
|
nr_channels++;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool filter(struct dma_chan *chan, void *param)
|
|
{
|
|
if (!dmatest_match_channel(chan) || !dmatest_match_device(chan->device))
|
|
return false;
|
|
else
|
|
return true;
|
|
}
|
|
|
|
static int __init dmatest_init(void)
|
|
{
|
|
dma_cap_mask_t mask;
|
|
struct dma_chan *chan;
|
|
int err = 0;
|
|
|
|
dma_cap_zero(mask);
|
|
dma_cap_set(DMA_MEMCPY, mask);
|
|
for (;;) {
|
|
chan = dma_request_channel(mask, filter, NULL);
|
|
if (chan) {
|
|
err = dmatest_add_channel(chan);
|
|
if (err) {
|
|
dma_release_channel(chan);
|
|
break; /* add_channel failed, punt */
|
|
}
|
|
} else
|
|
break; /* no more channels available */
|
|
if (max_channels && nr_channels >= max_channels)
|
|
break; /* we have all we need */
|
|
}
|
|
|
|
return err;
|
|
}
|
|
/* when compiled-in wait for drivers to load first */
|
|
late_initcall(dmatest_init);
|
|
|
|
static void __exit dmatest_exit(void)
|
|
{
|
|
struct dmatest_chan *dtc, *_dtc;
|
|
struct dma_chan *chan;
|
|
|
|
list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) {
|
|
list_del(&dtc->node);
|
|
chan = dtc->chan;
|
|
dmatest_cleanup_channel(dtc);
|
|
pr_debug("dmatest: dropped channel %s\n",
|
|
dma_chan_name(chan));
|
|
dma_release_channel(chan);
|
|
}
|
|
}
|
|
module_exit(dmatest_exit);
|
|
|
|
MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
|
|
MODULE_LICENSE("GPL v2");
|