Parameters like maximum read/write request size and the maximum
number of active transactions are currently configured in DT/ACPI.
This patch allows a user to override these to fine tune performance
for their application.
Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/dma/qcom/hidma.c | 7 +++++--
drivers/dma/qcom/hidma_mgmt.c | 47 ++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 51 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
index 5072a7d..84e3699 100644
--- a/drivers/dma/qcom/hidma.c
+++ b/drivers/dma/qcom/hidma.c
@@ -1,7 +1,7 @@
/*
* Qualcomm Technologies HIDMA DMA engine interface
*
- * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -795,8 +795,11 @@ static int hidma_probe(struct platform_device *pdev)
device_property_read_u32(&pdev->dev, "desc-count",
&dmadev->nr_descriptors);
- if (!dmadev->nr_descriptors && nr_desc_prm)
+ if (nr_desc_prm) {
+ dev_info(&pdev->dev, "overriding number of descriptors as %d\n",
+ nr_desc_prm);
dmadev->nr_descriptors = nr_desc_prm;
+ }
if (!dmadev->nr_descriptors)
dmadev->nr_descriptors = HIDMA_NR_DEFAULT_DESC;
diff --git a/drivers/dma/qcom/hidma_mgmt.c b/drivers/dma/qcom/hidma_mgmt.c
index f847d32..5a0991b 100644
--- a/drivers/dma/qcom/hidma_mgmt.c
+++ b/drivers/dma/qcom/hidma_mgmt.c
@@ -1,7 +1,7 @@
/*
* Qualcomm Technologies HIDMA DMA engine Management interface
*
- * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -49,6 +49,26 @@
#define HIDMA_AUTOSUSPEND_TIMEOUT 2000
#define HIDMA_MAX_CHANNEL_WEIGHT 15
+static unsigned int max_write_request;
+module_param(max_write_request, uint, 0644);
+MODULE_PARM_DESC(max_write_request,
+ "maximum write burst (default: ACPI/DT value)");
+
+static unsigned int max_read_request;
+module_param(max_read_request, uint, 0644);
+MODULE_PARM_DESC(max_read_request,
+ "maximum read burst (default: ACPI/DT value)");
+
+static unsigned int max_wr_xactions;
+module_param(max_wr_xactions, uint, 0644);
+MODULE_PARM_DESC(max_wr_xactions,
+ "maximum number of write transactions (default: ACPI/DT value)");
+
+static unsigned int max_rd_xactions;
+module_param(max_rd_xactions, uint, 0644);
+MODULE_PARM_DESC(max_rd_xactions,
+ "maximum number of read transactions (default: ACPI/DT value)");
+
int hidma_mgmt_setup(struct hidma_mgmt_dev *mgmtdev)
{
unsigned int i;
@@ -207,12 +227,25 @@ static int hidma_mgmt_probe(struct platform_device *pdev)
goto out;
}
+ if (max_write_request) {
+ dev_info(&pdev->dev, "overriding max-write-burst-bytes: %d\n",
+ max_write_request);
+ mgmtdev->max_write_request = max_write_request;
+ } else
+ max_write_request = mgmtdev->max_write_request;
+
rc = device_property_read_u32(&pdev->dev, "max-read-burst-bytes",
&mgmtdev->max_read_request);
if (rc) {
dev_err(&pdev->dev, "max-read-burst-bytes missing\n");
goto out;
}
+ if (max_read_request) {
+ dev_info(&pdev->dev, "overriding max-read-burst-bytes: %d\n",
+ max_read_request);
+ mgmtdev->max_read_request = max_read_request;
+ } else
+ max_read_request = mgmtdev->max_read_request;
rc = device_property_read_u32(&pdev->dev, "max-write-transactions",
&mgmtdev->max_wr_xactions);
@@ -220,6 +253,12 @@ static int hidma_mgmt_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "max-write-transactions missing\n");
goto out;
}
+ if (max_wr_xactions) {
+ dev_info(&pdev->dev, "overriding max-write-transactions: %d\n",
+ max_wr_xactions);
+ mgmtdev->max_wr_xactions = max_wr_xactions;
+ } else
+ max_wr_xactions = mgmtdev->max_wr_xactions;
rc = device_property_read_u32(&pdev->dev, "max-read-transactions",
&mgmtdev->max_rd_xactions);
@@ -227,6 +266,12 @@ static int hidma_mgmt_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "max-read-transactions missing\n");
goto out;
}
+ if (max_rd_xactions) {
+ dev_info(&pdev->dev, "overriding max-read-transactions: %d\n",
+ max_rd_xactions);
+ mgmtdev->max_rd_xactions = max_rd_xactions;
+ } else
+ max_rd_xactions = mgmtdev->max_rd_xactions;
mgmtdev->priority = devm_kcalloc(&pdev->dev,
mgmtdev->dma_channels,
--
1.9.1
--
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