From 7edacbdede43858b7c37b978906eff2d3d30f73b Mon Sep 17 00:00:00 2001
From: Cai YiWei <cyw@rock-chips.com>
Date: Wed, 15 May 2019 17:01:55 +0800
Subject: [PATCH] media: rockchip: isp1: support get continuous memory from
 specific CMA region

If no IOMMU support for ISP, we prefer to alloc continuous
physical memory from our reserved CMA region than from system
reserved.

Change-Id: I1e598ee7309c9c53254649f5267a1e7f515c6361
Signed-off-by: Cai YiWei <cyw@rock-chips.com>
---
 drivers/media/platform/rockchip/isp1/dev.c | 26 ++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/media/platform/rockchip/isp1/dev.c b/drivers/media/platform/rockchip/isp1/dev.c
index 71b1947cab8b..23f69c7373bc 100644
--- a/drivers/media/platform/rockchip/isp1/dev.c
+++ b/drivers/media/platform/rockchip/isp1/dev.c
@@ -40,6 +40,7 @@
 #include <linux/of_gpio.h>
 #include <linux/of_graph.h>
 #include <linux/of_platform.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/pm_runtime.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/regmap.h>
@@ -914,6 +915,24 @@ err:
 	return ret;
 }
 
+static inline bool is_iommu_enable(struct device *dev)
+{
+	struct device_node *iommu;
+
+	iommu = of_parse_phandle(dev->of_node, "iommus", 0);
+	if (!iommu) {
+		dev_info(dev, "no iommu attached, using non-iommu buffers\n");
+		return false;
+	} else if (!of_device_is_available(iommu)) {
+		dev_info(dev, "iommu is disabled, using non-iommu buffers\n");
+		of_node_put(iommu);
+		return false;
+	}
+	of_node_put(iommu);
+
+	return true;
+}
+
 static int rkisp1_vs_irq_parse(struct platform_device *pdev)
 {
 	int ret;
@@ -1105,6 +1124,13 @@ static int rkisp1_plat_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_unreg_media_dev;
 
+	if (!is_iommu_enable(dev)) {
+		ret = of_reserved_mem_device_init(dev);
+		if (ret)
+			v4l2_warn(v4l2_dev,
+				  "No reserved memory region assign to isp\n");
+	}
+
 	pm_runtime_enable(&pdev->dev);
 
 	ret = rkisp1_vs_irq_parse(pdev);