diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/dma/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/dma/Makefile | 1 | ||||
| -rw-r--r-- | drivers/dma/dmatest.c | 444 |
3 files changed, 452 insertions, 0 deletions
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 5af8b1cfc1e9..4b6bd3d099cf 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -72,4 +72,11 @@ config NET_DMA Say Y here if you enabled INTEL_IOATDMA or FSL_DMA, otherwise say N. +config DMATEST + tristate "DMA Test client" + depends on DMA_ENGINE + help + Simple DMA test client. Say N unless you're debugging a + DMA Device driver. + endif diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index ee272fd329c9..181e3646fbfe 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_DMA_ENGINE) += dmaengine.o obj-$(CONFIG_NET_DMA) += iovlock.o +obj-$(CONFIG_DMATEST) += dmatest.o obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o ioatdma-objs := ioat.o ioat_dma.o ioat_dca.o obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c new file mode 100644 index 000000000000..a08d19704743 --- /dev/null +++ b/drivers/dma/dmatest.c @@ -0,0 +1,444 @@ +/* + * DMA Engine test module + * + * Copyright (C) 2007 Atmel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/init.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/random.h> +#include <linux/wait.h> + +static unsigned int test_buf_size = 16384; +module_param(test_buf_size, uint, S_IRUGO); +MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer"); + +static char test_channel[BUS_ID_SIZE]; +module_param_string(channel, test_channel, sizeof(test_channel), S_IRUGO); +MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)"); + +static char test_device[BUS_ID_SIZE]; +module_param_string(device, test_device, sizeof(test_device), S_IRUGO); +MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)"); + +static unsigned int threads_per_chan = 1; +module_param(threads_per_chan, uint, S_IRUGO); +MODULE_PARM_DESC(threads_per_chan, + "Number of threads to start per channel (default: 1)"); + +static unsigned int max_channels; +module_param(max_channels, uint, S_IRUGO); +MODULE_PARM_DESC(nr_channels, + "Maximum number of channels to use (default: all)"); + +/* + * Initialization patterns. All bytes in the source buffer has bit 7 + * set, all bytes in the destination buffer has bit 7 cleared. + * + * Bit 6 is set for all bytes which are to be copied by the DMA + * engine. Bit 5 is set for all bytes which are to be overwritten by + * the DMA engine. + * + * The remaining bits are the inverse of a counter which increments by + * one for each byte address. + */ +#define PATTERN_SRC 0x80 +#define PATTERN_DST 0x00 +#define PATTERN_COPY 0x40 +#define PATTERN_OVERWRITE 0x20 +#define PATTERN_COUNT_MASK 0x1f + +struct dmatest_thread { + struct list_head node; + struct task_struct *task; + struct dma_chan *chan; + u8 *srcbuf; + u8 *dstbuf; +}; + +struct dmatest_chan { + struct list_head node; + struct dma_chan *chan; + struct list_head threads; +}; + +/* + * These are protected by dma_list_mutex since they're only used by + * the DMA client event callback + */ +static LIST_HEAD(dmatest_channels); +static unsigned int nr_channels; + +static bool dmatest_match_channel(struct dma_chan *chan) +{ + if (test_channel[0] == '\0') + return true; + return strcmp(chan->dev.bus_id, test_channel) == 0; +} + +static bool dmatest_match_device(struct dma_device *device) +{ + if (test_device[0] == '\0') + return true; + return strcmp(device->dev->bus_id, test_device) == 0; +} + +static unsigned long dmatest_random(void) +{ + unsigned long buf; + + get_random_bytes(&buf, sizeof(buf)); + return buf; +} + +static void dmatest_init_srcbuf(u8 *buf, unsigned int start, unsigned int len) +{ + unsigned int i; + + for (i = 0; i < start; i++) + buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); + for ( ; i < start + len; i++) + buf[i] = PATTERN_SRC | PATTERN_COPY + | (~i & PATTERN_COUNT_MASK);; + for ( ; i < test_buf_size; i++) + buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); +} + +static void dmatest_init_dstbuf(u8 *buf, unsigned int start, unsigned int len) +{ + unsigned int i; + + for (i = 0; i < start; i++) + buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); + for ( ; i < start + len; i++) + buf[i] = PATTERN_DST | PATTERN_OVERWRITE + | (~i & PATTERN_COUNT_MASK); + for ( ; i < test_buf_size; i++) + buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); +} + +static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index, + unsigned int counter, bool is_srcbuf) +{ + u8 diff = actual ^ pattern; + u8 expected = pattern | (~counter & PATTERN_COUNT_MASK); + const char *thread_name = current->comm; + + if (is_srcbuf) + pr_warning("%s: srcbuf[0x%x] overwritten!" + " Expected %02x, got %02x\n", + thread_name, index, expected, actual); + else if ((pattern & PATTERN_COPY) + && (diff & (PATTERN_COPY | PATTERN_OVERWRITE))) + pr_warning("%s: dstbuf[0x%x] not copied!" + " Expected %02x, got %02x\n", + thread_name, index, expected, actual); + else if (diff & PATTERN_SRC) + pr_warning("%s: dstbuf[0x%x] was copied!" + " Expected %02x, got %02x\n", + thread_name, index, expected, actual); + else + pr_warning("%s: dstbuf[0x%x] mismatch!" + " Expected %02x, got %02x\n", + thread_name, index, expected, actual); +} + +static unsigned int dmatest_verify(u8 *buf, unsigned int start, + unsigned int end, unsigned int counter, u8 pattern, + bool is_srcbuf) +{ + unsigned int i; + unsigned int error_count = 0; + u8 actual; + + for (i = start; i < end; i++) { + actual = buf[i]; + if (actual != (pattern | (~counter & PATTERN_COUNT_MASK))) { + if (error_count < 32) + dmatest_mismatch(actual, pattern, i, counter, + is_srcbuf); + error_count++; + } + counter++; + } + + if (error_count > 32) + pr_warning("%s: %u errors suppressed\n", + current->comm, error_count - 32); + + return error_count; +} + +/* + * This function repeatedly tests DMA transfers of various lengths and + * offsets until it is told to exit by kthread_stop(). There may be + * multiple threads running this function in parallel for a single + * channel, and there may be multiple channels being tested in + * parallel. + * + * Before each test, the source and destination buffer is initialized + * with a known pattern. This pattern is different depending on + * whether it's in an area which is supposed to be copied or + * overwritten, and different in the source and destination buffers. + * So if the DMA engine doesn't copy exactly what we tell it to copy, + * we'll notice. + */ +static int dmatest_func(void *data) +{ + struct dmatest_thread *thread = data; + struct dma_chan *chan; + const char *thread_name; + unsigned int src_off, dst_off, len; + unsigned int error_count; + unsigned int failed_tests = 0; + unsigned int total_tests = 0; + dma_cookie_t cookie; + enum dma_status status; + int ret; + + thread_name = current->comm; + + ret = -ENOMEM; + thread->srcbuf = kmalloc(test_buf_size, GFP_KERNEL); + if (!thread->srcbuf) + goto err_srcbuf; + thread->dstbuf = kmalloc(test_buf_size, GFP_KERNEL); + if (!thread->dstbuf) + goto err_dstbuf; + + smp_rmb(); + chan = thread->chan; + dma_chan_get(chan); + + while (!kthread_should_stop()) { + total_tests++; + + len = dmatest_random() % test_buf_size + 1; + src_off = dmatest_random() % (test_buf_size - len + 1); + dst_off = dmatest_random() % (test_buf_size - len + 1); + + dmatest_init_srcbuf(thread->srcbuf, src_off, len); + dmatest_init_dstbuf(thread->dstbuf, dst_off, len); + + cookie = dma_async_memcpy_buf_to_buf(chan, + thread->dstbuf + dst_off, + thread->srcbuf + src_off, + len); + if (dma_submit_error(cookie)) { + pr_warning("%s: #%u: submit error %d with src_off=0x%x " + "dst_off=0x%x len=0x%x\n", + thread_name, total_tests - 1, cookie, + src_off, dst_off, len); + msleep(100); + failed_tests++; + continue; + } + dma_async_memcpy_issue_pending(chan); + + do { + msleep(1); + status = dma_async_memcpy_complete( + chan, cookie, NULL, NULL); + } while (status == DMA_IN_PROGRESS); + + if (status == DMA_ERROR) { + pr_warning("%s: #%u: error during copy\n", + thread_name, total_tests - 1); + failed_tests++; + continue; + } + + error_count = 0; + + pr_debug("%s: verifying source buffer...\n", thread_name); + error_count += dmatest_verify(thread->srcbuf, 0, src_off, + 0, PATTERN_SRC, true); + error_count += dmatest_verify(thread->srcbuf, src_off, + src_off + len, src_off, + PATTERN_SRC | PATTERN_COPY, true); + error_count += dmatest_verify(thread->srcbuf, src_off + len, + test_buf_size, src_off + len, + PATTERN_SRC, true); + + pr_debug("%s: verifying dest buffer...\n", + thread->task->comm); + error_count += dmatest_verify(thread->dstbuf, 0, dst_off, + 0, PATTERN_DST, false); + error_count += dmatest_verify(thread->dstbuf, dst_off, + dst_off + len, src_off, + PATTERN_SRC | PATTERN_COPY, false); + error_count += dmatest_verify(thread->dstbuf, dst_off + len, + test_buf_size, dst_off + len, + PATTERN_DST, false); + + if (error_count) { + pr_warning("%s: #%u: %u errors with " + "src_off=0x%x dst_off=0x%x len=0x%x\n", + thread_name, total_tests - 1, error_count, + src_off, dst_off, len); + failed_tests++; + } else { + pr_debug("%s: #%u: No errors with " + "src_off=0x%x dst_off=0x%x len=0x%x\n", + thread_name, total_tests - 1, + src_off, dst_off, len); + } + } + + ret = 0; + dma_chan_put(chan); + kfree(thread->dstbuf); +err_dstbuf: + kfree(thread->srcbuf); +err_srcbuf: + pr_notice("%s: terminating after %u tests, %u failures (status %d)\n", + thread_name, total_tests, failed_tests, ret); + return ret; +} + +static void dmatest_cleanup_channel(struct dmatest_chan *dtc) +{ + struct dmatest_thread *thread; + 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 enum dma_state_client dmatest_add_channel(struct dma_chan *chan) +{ + struct dmatest_chan *dtc; + struct dmatest_thread *thread; + unsigned int i; + + dtc = kmalloc(sizeof(struct dmatest_chan), GFP_ATOMIC); + if (!dtc) { + pr_warning("dmatest: No memory for %s\n", chan->dev.bus_id); + return DMA_NAK; + } + + dtc->chan = chan; + INIT_LIST_HEAD(&dtc->threads); + + 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-test%u\n", + chan->dev.bus_id, i); + break; + } + thread->chan = dtc->chan; + smp_wmb(); + thread->task = kthread_run(dmatest_func, thread, "%s-test%u", + chan->dev.bus_id, i); + if (IS_ERR(thread->task)) { + pr_warning("dmatest: Failed to run thread %s-test%u\n", + chan->dev.bus_id, i); + kfree(thread); + break; + } + + /* srcbuf and dstbuf are allocated by the thread itself */ + + list_add_tail(&thread->node, &dtc->threads); + } + + pr_info("dmatest: Started %u threads using %s\n", i, chan->dev.bus_id); + + list_add_tail(&dtc->node, &dmatest_channels); + nr_channels++; + + return DMA_ACK; +} + +static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan) +{ + struct dmatest_chan *dtc, *_dtc; + + list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { + if (dtc->chan == chan) { + list_del(&dtc->node); + dmatest_cleanup_channel(dtc); + pr_debug("dmatest: lost channel %s\n", + chan->dev.bus_id); + return DMA_ACK; + } + } + + return DMA_DUP; +} + +/* + * Start testing threads as new channels are assigned to us, and kill + * them when the channels go away. + * + * When we unregister the client, all channels are removed so this + * will also take care of cleaning things up when the module is + * unloaded. + */ +static enum dma_state_client +dmatest_event(struct dma_client *client, struct dma_chan *chan, + enum dma_state state) +{ + enum dma_state_client ack = DMA_NAK; + + switch (state) { + case DMA_RESOURCE_AVAILABLE: + if (!dmatest_match_channel(chan) + || !dmatest_match_device(chan->device)) + ack = DMA_DUP; + else if (max_channels && nr_channels >= max_channels) + ack = DMA_NAK; + else + ack = dmatest_add_channel(chan); + break; + + case DMA_RESOURCE_REMOVED: + ack = dmatest_remove_channel(chan); + break; + + default: + pr_info("dmatest: Unhandled event %u (%s)\n", + state, chan->dev.bus_id); + break; + } + + return ack; +} + +static struct dma_client dmatest_client = { + .event_callback = dmatest_event, +}; + +static int __init dmatest_init(void) +{ + dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask); + dma_async_client_register(&dmatest_client); + dma_async_client_chan_request(&dmatest_client); + + return 0; +} +module_init(dmatest_init); + +static void __exit dmatest_exit(void) +{ + dma_async_client_unregister(&dmatest_client); +} +module_exit(dmatest_exit); + +MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>"); +MODULE_LICENSE("GPL v2"); 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