[PATCH v4 7/7] mtd: rawnand: loongson: Add Loongson-2K1000 NAND controller support

[Binbin Zhou]

The Loongson-2K1000 NAND controller is also similar to the Loongson-1C.

It supports a maximum capacity of 16GB FLASH per chip with a maximum
page size of 8KB, and it supports up to 4 chip selects and 4 RDY
signals.

The key difference from the Loongson-2K0500 is that it requires explicit
configuration of the DMA control route. Typically, it is configured as
APBDMA0.

Signed-off-by: Binbin Zhou <zhoubinbin at loongson.cn>
---
 .../mtd/nand/raw/loongson-nand-controller.c   | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/drivers/mtd/nand/raw/loongson-nand-controller.c b/drivers/mtd/nand/raw/loongson-nand-controller.c
index 427a0daf8c55..8490412d5be1 100644
--- a/drivers/mtd/nand/raw/loongson-nand-controller.c
+++ b/drivers/mtd/nand/raw/loongson-nand-controller.c
@@ -74,6 +74,14 @@
 
 #define BITS_PER_WORD			(4 * BITS_PER_BYTE)
 
+/* Loongson-2K1000 NAND DMA routing register */
+#define LS2K1000_NAND_DMA_MASK         GENMASK(2, 0)
+#define LS2K1000_DMA0_CONF             0x0
+#define LS2K1000_DMA1_CONF             0x1
+#define LS2K1000_DMA2_CONF             0x2
+#define LS2K1000_DMA3_CONF             0x3
+#define LS2K1000_DMA4_CONF             0x4
+
 struct loongson_nand_host;
 
 struct loongson_nand_op {
@@ -103,6 +111,7 @@ struct loongson_nand_data {
 	unsigned int wait_cycle;
 	unsigned int nand_cs;
 	unsigned int dma_bits;
+	int (*dma_config)(struct device *dev);
 	void (*set_addr)(struct loongson_nand_host *host, struct loongson_nand_op *op);
 };
 
@@ -759,6 +768,23 @@ static void loongson_nand_controller_cleanup(struct loongson_nand_host *host)
 		dma_release_channel(host->dma_chan);
 }
 
+static int ls2k1000_nand_apbdma_config(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	void __iomem *regs;
+	int val;
+
+	regs = devm_platform_ioremap_resource_byname(pdev, "dma-config");
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	val = readl(regs);
+	val |= FIELD_PREP(LS2K1000_NAND_DMA_MASK, LS2K1000_DMA0_CONF);
+	writel(val, regs);
+
+	return 0;
+}
+
 static int loongson_nand_controller_init(struct loongson_nand_host *host)
 {
 	struct device *dev = host->dev;
@@ -787,6 +813,12 @@ static int loongson_nand_controller_init(struct loongson_nand_host *host)
 
 	regmap_write(host->regmap, LOONGSON_NAND_CS_RDY_MAP, val);
 
+	if (host->data->dma_config) {
+		ret = host->data->dma_config(dev);
+		if (ret)
+			return dev_err_probe(dev, ret, "failed to config DMA routing\n");
+	}
+
 	chan = dma_request_chan(dev, "rxtx");
 	if (IS_ERR(chan))
 		return dev_err_probe(dev, PTR_ERR(chan), "failed to request DMA channel\n");
@@ -941,6 +973,19 @@ static const struct loongson_nand_data ls2k0500_nand_data = {
 	.set_addr = ls1c_nand_set_addr,
 };
 
+static const struct loongson_nand_data ls2k1000_nand_data = {
+	.max_id_cycle = 6,
+	.id_cycle_field = GENMASK(14, 12),
+	.status_field = GENMASK(23, 16),
+	.op_scope_field = GENMASK(29, 16),
+	.hold_cycle = 0x4,
+	.wait_cycle = 0x12,
+	.nand_cs = 0x2,
+	.dma_bits = 64,
+	.dma_config = ls2k1000_nand_apbdma_config,
+	.set_addr = ls1c_nand_set_addr,
+};
+
 static const struct of_device_id loongson_nand_match[] = {
 	{
 		.compatible = "loongson,ls1b-nand-controller",
@@ -954,6 +999,10 @@ static const struct of_device_id loongson_nand_match[] = {
 		.compatible = "loongson,ls2k0500-nand-controller",
 		.data = &ls2k0500_nand_data,
 	},
+	{
+		.compatible = "loongson,ls2k1000-nand-controller",
+		.data = &ls2k1000_nand_data,
+	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, loongson_nand_match);
-- 
2.47.3