Merge tag 'dmaengine-4.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:
 "This time we have aded a new capability for scatter-gathered memset
  using dmaengine APIs.  This is supported in xdmac & hdmac drivers

  We have added support for reusing descriptors for examples like video
  buffers etc.  Driver will follow

  The behaviour of descriptor ack has been clarified and documented

  New devices added are:
   - dma controller in sun[457]i SoCs
   - lpc18xx dmamux
   - ZTE ZX296702 dma controller
   - Analog Devices AXI-DMAC DMA controller
   - eDMA support for dma-crossbar
   - imx6sx support in imx-sdma driver
   - imx-sdma device to device support

  Other:
   - jz4780 fixes
   - ioatdma large refactor and cleanup for removal of ioat v1 and v2
     which is deprecated and fixes
   - ACPI support in X-Gene DMA engine driver
   - ipu irq fixes
   - mvxor fixes
   - minor fixes spread thru drivers"

[ The Kconfig and Makefile entries got re-sorted alphabetically, and I
  handled the conflict with the new Intel integrated IDMA driver by
  slightly mis-sorting it on purpose: "IDMA64" got sorted after "IMX" in
  order to keep the Intel entries together.  I think it might be a good
  idea to just rename the IDMA64 config entry to INTEL_IDMA64 to make
  the sorting be a true sort, not this mismash.

  Also, this merge disables the COMPILE_TEST for the sun4i DMA
  controller, because it does not compile cleanly at all.     - Linus ]

* tag 'dmaengine-4.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (89 commits)
  dmaengine: ioatdma: add Broadwell EP ioatdma PCI dev IDs
  dmaengine :ipu: change ipu_irq_handler() to remove compile warning
  dmaengine: ioatdma: Fix variable array length
  dmaengine: ioatdma: fix sparse "error" with prep lock
  dmaengine: hdmac: Add memset capabilities
  dmaengine: sort the sh Makefile
  dmaengine: sort the sh Kconfig
  dmaengine: sort the dw Kconfig
  dmaengine: sort the Kconfig
  dmaengine: sort the makefile
  drivers/dma: make mv_xor.c driver explicitly non-modular
  dmaengine: Add support for the Analog Devices AXI-DMAC DMA controller
  devicetree: Add bindings documentation for Analog Devices AXI-DMAC
  dmaengine: xgene-dma: Fix the lock to allow client for further submission of requests
  dmaengine: ioatdma: fix coccinelle warning
  dmaengine: ioatdma: fix zero day warning on incompatible pointer type
  dmaengine: tegra-apb: Simplify locking for device using global pause
  dmaengine: tegra-apb: Remove unnecessary return statements and variables
  dmaengine: tegra-apb: Avoid unnecessary channel base address calculation
  dmaengine: tegra-apb: Remove unused variables
  ...

1 files changed, 29 insertions, 40 deletions

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index f1325f62563e..1c2de9a834a9 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -13,7 +13,6 @@
  */
 
 #include <linux/init.h>
-#include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
@@ -26,6 +25,7 @@
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/irqdomain.h>
+#include <linux/cpumask.h>
 #include <linux/platform_data/dma-mv_xor.h>
 
 #include "dmaengine.h"
@@ -1126,7 +1126,8 @@ static const struct of_device_id mv_xor_dt_ids[] = {
 	{ .compatible = "marvell,armada-380-xor", .data = (void *)XOR_MODE_IN_DESC },
 	{},
 };
-MODULE_DEVICE_TABLE(of, mv_xor_dt_ids);
+
+static unsigned int mv_xor_engine_count;
 
 static int mv_xor_probe(struct platform_device *pdev)
 {
@@ -1134,6 +1135,7 @@ static int mv_xor_probe(struct platform_device *pdev)
 	struct mv_xor_device *xordev;
 	struct mv_xor_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct resource *res;
+	unsigned int max_engines, max_channels;
 	int i, ret;
 	int op_in_desc;
 
@@ -1177,6 +1179,21 @@ static int mv_xor_probe(struct platform_device *pdev)
 	if (!IS_ERR(xordev->clk))
 		clk_prepare_enable(xordev->clk);
 
+	/*
+	 * We don't want to have more than one channel per CPU in
+	 * order for async_tx to perform well. So we limit the number
+	 * of engines and channels so that we take into account this
+	 * constraint. Note that we also want to use channels from
+	 * separate engines when possible.
+	 */
+	max_engines = num_present_cpus();
+	max_channels = min_t(unsigned int,
+			     MV_XOR_MAX_CHANNELS,
+			     DIV_ROUND_UP(num_present_cpus(), 2));
+
+	if (mv_xor_engine_count >= max_engines)
+		return 0;
+
 	if (pdev->dev.of_node) {
 		struct device_node *np;
 		int i = 0;
@@ -1190,13 +1207,13 @@ static int mv_xor_probe(struct platform_device *pdev)
 			int irq;
 			op_in_desc = (int)of_id->data;
 
+			if (i >= max_channels)
+				continue;
+
 			dma_cap_zero(cap_mask);
-			if (of_property_read_bool(np, "dmacap,memcpy"))
-				dma_cap_set(DMA_MEMCPY, cap_mask);
-			if (of_property_read_bool(np, "dmacap,xor"))
-				dma_cap_set(DMA_XOR, cap_mask);
-			if (of_property_read_bool(np, "dmacap,interrupt"))
-				dma_cap_set(DMA_INTERRUPT, cap_mask);
+			dma_cap_set(DMA_MEMCPY, cap_mask);
+			dma_cap_set(DMA_XOR, cap_mask);
+			dma_cap_set(DMA_INTERRUPT, cap_mask);
 
 			irq = irq_of_parse_and_map(np, 0);
 			if (!irq) {
@@ -1216,7 +1233,7 @@ static int mv_xor_probe(struct platform_device *pdev)
 			i++;
 		}
 	} else if (pdata && pdata->channels) {
-		for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+		for (i = 0; i < max_channels; i++) {
 			struct mv_xor_channel_data *cd;
 			struct mv_xor_chan *chan;
 			int irq;
@@ -1263,27 +1280,8 @@ err_channel_add:
 	return ret;
 }
 
-static int mv_xor_remove(struct platform_device *pdev)
-{
-	struct mv_xor_device *xordev = platform_get_drvdata(pdev);
-	int i;
-
-	for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
-		if (xordev->channels[i])
-			mv_xor_channel_remove(xordev->channels[i]);
-	}
-
-	if (!IS_ERR(xordev->clk)) {
-		clk_disable_unprepare(xordev->clk);
-		clk_put(xordev->clk);
-	}
-
-	return 0;
-}
-
 static struct platform_driver mv_xor_driver = {
 	.probe		= mv_xor_probe,
-	.remove		= mv_xor_remove,
 	.driver		= {
 		.name	        = MV_XOR_NAME,
 		.of_match_table = of_match_ptr(mv_xor_dt_ids),
@@ -1295,19 +1293,10 @@ static int __init mv_xor_init(void)
 {
 	return platform_driver_register(&mv_xor_driver);
 }
-module_init(mv_xor_init);
-
-/* it's currently unsafe to unload this module */
-#if 0
-static void __exit mv_xor_exit(void)
-{
-	platform_driver_unregister(&mv_xor_driver);
-	return;
-}
-
-module_exit(mv_xor_exit);
-#endif
+device_initcall(mv_xor_init);
 
+/*
 MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>");
 MODULE_DESCRIPTION("DMA engine driver for Marvell's XOR engine");
 MODULE_LICENSE("GPL");
+*/