From 889f7522e4246f63c0c1e92047aa7fe0fa076774 Mon Sep 17 00:00:00 2001
From: Simon Xue <xxm@rock-chips.com>
Date: Wed, 24 Nov 2021 17:59:46 +0800
Subject: [PATCH] pcie-dma-trx: update to version 0x3

support reverse buffer address

if reverse
	buf_idx 0-7	rc <- ep
	buf_idx 8-15	rc -> ep
else
	buf_idx 0-7	rc -> ep
	buf_idx 8-15	rc <- ep

Should update test-pcie:

rc: ./test-pcie 2 1000 1024 0 0
ep: ./test-pcie 1 1000 1024 0 0

Change-Id: I73cd6cb3511068166d5681f44a7f53d46003775b
Signed-off-by: Simon Xue <xxm@rock-chips.com>
---
 drivers/pci/controller/rockchip-pcie-dma.c | 41 ++++++++++++++++------
 drivers/pci/controller/rockchip-pcie-dma.h |  1 +
 2 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/controller/rockchip-pcie-dma.c b/drivers/pci/controller/rockchip-pcie-dma.c
index 7f9a369d4b0c..000b686c7aa3 100644
--- a/drivers/pci/controller/rockchip-pcie-dma.c
+++ b/drivers/pci/controller/rockchip-pcie-dma.c
@@ -168,10 +168,18 @@ static void rk_pcie_prepare_dma(struct dma_trx_obj *obj,
 		bus = obj->remote_mem_start + bus_idx * obj->buffer_size;
 		virt = obj->local_mem_base + local_idx * obj->buffer_size;
 
-		if (!is_rc(obj)) {
-			local += obj->rd_buf_size;
-			virt += obj->rd_buf_size;
-			bus += obj->wr_buf_size;
+		if (obj->addr_reverse) {
+			if (is_rc(obj)) {
+				local += obj->rd_buf_size;
+				virt += obj->rd_buf_size;
+				bus += obj->wr_buf_size;
+			}
+		} else {
+			if (!is_rc(obj)) {
+				local += obj->rd_buf_size;
+				virt += obj->rd_buf_size;
+				bus += obj->wr_buf_size;
+			}
 		}
 
 		obj->begin = ktime_get();
@@ -315,11 +323,17 @@ static enum hrtimer_restart rk_pcie_scan_timer(struct hrtimer *timer)
 	for (i = 0; i < PCIE_DMA_BUF_CNT; i++) {
 		sda_base = obj->local_mem_base + obj->buffer_size * i;
 
-		if (is_rc(obj))
-			scan_data_addr =  sda_base + obj->rd_buf_size;
-		else
-			scan_data_addr = sda_base;
-
+		if (obj->addr_reverse) {
+			if (is_rc(obj))
+				scan_data_addr = sda_base;
+			else
+				scan_data_addr =  sda_base + obj->rd_buf_size;
+		} else {
+			if (is_rc(obj))
+				scan_data_addr =  sda_base + obj->rd_buf_size;
+			else
+				scan_data_addr = sda_base;
+		}
 		sdv = readl(scan_data_addr + obj->set_data_check_pos);
 		idx = readl(scan_data_addr + obj->set_local_idx_pos);
 
@@ -815,6 +829,7 @@ struct dma_trx_obj *rk_pcie_dma_obj_probe(struct device *dev)
 	struct device_node *mem;
 	struct resource reg;
 	struct dma_trx_obj *obj;
+	int reverse;
 
 	obj = devm_kzalloc(dev, sizeof(struct dma_trx_obj), GFP_KERNEL);
 	if (!obj)
@@ -830,6 +845,12 @@ struct dma_trx_obj *rk_pcie_dma_obj_probe(struct device *dev)
 
 	obj->busno = busno;
 
+	ret = of_property_read_u32(np, "reverse", &reverse);
+	if (ret < 0)
+		obj->addr_reverse = 0;
+	else
+		obj->addr_reverse = reverse;
+
 	mem = of_parse_phandle(np, "memory-region", 0);
 	if (!mem) {
 		dev_err(dev, "missing \"memory-region\" property\n");
@@ -898,7 +919,7 @@ struct dma_trx_obj *rk_pcie_dma_obj_probe(struct device *dev)
 	obj->irq_num = 0;
 	obj->loop_count_threshold = 0;
 	obj->ref_count = 0;
-	obj->version = 0x2;
+	obj->version = 0x3;
 	init_completion(&obj->done);
 
 	mutex_init(&obj->count_mutex);
diff --git a/drivers/pci/controller/rockchip-pcie-dma.h b/drivers/pci/controller/rockchip-pcie-dma.h
index a5d923445224..01f41947dac4 100644
--- a/drivers/pci/controller/rockchip-pcie-dma.h
+++ b/drivers/pci/controller/rockchip-pcie-dma.h
@@ -203,6 +203,7 @@ struct dma_trx_obj {
 	u32				set_buf_size_pos;
 	u32				set_chk_sum_pos;
 	u32				version;
+	int				addr_reverse;
 };
 
 #if IS_ENABLED(CONFIG_ROCKCHIP_PCIE_DMA_OBJ)