dmaengine: Add Synopsys eDMA IP version 0 support

Add support for the eDMA IP version 0 driver for both register maps (legacy
and unroll).

The legacy register mapping was the initial implementation, which consisted
in having all registers belonging to channels multiplexed, which could be
change anytime (which could led a race-condition) by view port register
(access to only one channel available each time).

This register mapping is not very effective and efficient in a multithread
environment, which has led to the development of unroll registers mapping,
which consists of having all channels registers accessible any time by
spreading all channels registers by an offset between them.

This version supports a maximum of 16 independent channels (8 write +
8 read), which can run simultaneously.

Implements a scatter-gather transfer through a linked list, where the size
of linked list depends on the allocated memory divided equally among all
channels.

Each linked list descriptor can transfer from 1 byte to 4 Gbytes and is
alignmented to DWORD.

Both SAR (Source Address Register) and DAR (Destination Address Register)
are alignmented to byte.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 158 insertions, 0 deletions

diff --git a/drivers/dma/dw-edma/dw-edma-v0-regs.h b/drivers/dma/dw-edma/dw-edma-v0-regs.h
new file mode 100644
index 000000000000..cd6476884507
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-edma-v0-regs.h
@@ -0,0 +1,158 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
+ * Synopsys DesignWare eDMA v0 core
+ *
+ * Author: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
+ */
+
+#ifndef _DW_EDMA_V0_REGS_H
+#define _DW_EDMA_V0_REGS_H
+
+#include <linux/dmaengine.h>
+
+#define EDMA_V0_MAX_NR_CH				8
+#define EDMA_V0_VIEWPORT_MASK				GENMASK(2, 0)
+#define EDMA_V0_DONE_INT_MASK				GENMASK(7, 0)
+#define EDMA_V0_ABORT_INT_MASK				GENMASK(23, 16)
+#define EDMA_V0_WRITE_CH_COUNT_MASK			GENMASK(3, 0)
+#define EDMA_V0_READ_CH_COUNT_MASK			GENMASK(19, 16)
+#define EDMA_V0_CH_STATUS_MASK				GENMASK(6, 5)
+#define EDMA_V0_DOORBELL_CH_MASK			GENMASK(2, 0)
+#define EDMA_V0_LINKED_LIST_ERR_MASK			GENMASK(7, 0)
+
+#define EDMA_V0_CH_ODD_MSI_DATA_MASK			GENMASK(31, 16)
+#define EDMA_V0_CH_EVEN_MSI_DATA_MASK			GENMASK(15, 0)
+
+struct dw_edma_v0_ch_regs {
+	u32 ch_control1;				/* 0x000 */
+	u32 ch_control2;				/* 0x004 */
+	u32 transfer_size;				/* 0x008 */
+	u32 sar_low;					/* 0x00c */
+	u32 sar_high;					/* 0x010 */
+	u32 dar_low;					/* 0x014 */
+	u32 dar_high;					/* 0x018 */
+	u32 llp_low;					/* 0x01c */
+	u32 llp_high;					/* 0x020 */
+};
+
+struct dw_edma_v0_ch {
+	struct dw_edma_v0_ch_regs wr;			/* 0x200 */
+	u32 padding_1[55];				/* [0x224..0x2fc] */
+	struct dw_edma_v0_ch_regs rd;			/* 0x300 */
+	u32 padding_2[55];				/* [0x224..0x2fc] */
+};
+
+struct dw_edma_v0_unroll {
+	u32 padding_1;					/* 0x0f8 */
+	u32 wr_engine_chgroup;				/* 0x100 */
+	u32 rd_engine_chgroup;				/* 0x104 */
+	u32 wr_engine_hshake_cnt_low;			/* 0x108 */
+	u32 wr_engine_hshake_cnt_high;			/* 0x10c */
+	u32 padding_2[2];				/* [0x110..0x114] */
+	u32 rd_engine_hshake_cnt_low;			/* 0x118 */
+	u32 rd_engine_hshake_cnt_high;			/* 0x11c */
+	u32 padding_3[2];				/* [0x120..0x124] */
+	u32 wr_ch0_pwr_en;				/* 0x128 */
+	u32 wr_ch1_pwr_en;				/* 0x12c */
+	u32 wr_ch2_pwr_en;				/* 0x130 */
+	u32 wr_ch3_pwr_en;				/* 0x134 */
+	u32 wr_ch4_pwr_en;				/* 0x138 */
+	u32 wr_ch5_pwr_en;				/* 0x13c */
+	u32 wr_ch6_pwr_en;				/* 0x140 */
+	u32 wr_ch7_pwr_en;				/* 0x144 */
+	u32 padding_4[8];				/* [0x148..0x164] */
+	u32 rd_ch0_pwr_en;				/* 0x168 */
+	u32 rd_ch1_pwr_en;				/* 0x16c */
+	u32 rd_ch2_pwr_en;				/* 0x170 */
+	u32 rd_ch3_pwr_en;				/* 0x174 */
+	u32 rd_ch4_pwr_en;				/* 0x178 */
+	u32 rd_ch5_pwr_en;				/* 0x18c */
+	u32 rd_ch6_pwr_en;				/* 0x180 */
+	u32 rd_ch7_pwr_en;				/* 0x184 */
+	u32 padding_5[30];				/* [0x188..0x1fc] */
+	struct dw_edma_v0_ch ch[EDMA_V0_MAX_NR_CH];	/* [0x200..0x1120] */
+};
+
+struct dw_edma_v0_legacy {
+	u32 viewport_sel;				/* 0x0f8 */
+	struct dw_edma_v0_ch_regs ch;			/* [0x100..0x120] */
+};
+
+struct dw_edma_v0_regs {
+	/* eDMA global registers */
+	u32 ctrl_data_arb_prior;			/* 0x000 */
+	u32 padding_1;					/* 0x004 */
+	u32 ctrl;					/* 0x008 */
+	u32 wr_engine_en;				/* 0x00c */
+	u32 wr_doorbell;				/* 0x010 */
+	u32 padding_2;					/* 0x014 */
+	u32 wr_ch_arb_weight_low;			/* 0x018 */
+	u32 wr_ch_arb_weight_high;			/* 0x01c */
+	u32 padding_3[3];				/* [0x020..0x028] */
+	u32 rd_engine_en;				/* 0x02c */
+	u32 rd_doorbell;				/* 0x030 */
+	u32 padding_4;					/* 0x034 */
+	u32 rd_ch_arb_weight_low;			/* 0x038 */
+	u32 rd_ch_arb_weight_high;			/* 0x03c */
+	u32 padding_5[3];				/* [0x040..0x048] */
+	/* eDMA interrupts registers */
+	u32 wr_int_status;				/* 0x04c */
+	u32 padding_6;					/* 0x050 */
+	u32 wr_int_mask;				/* 0x054 */
+	u32 wr_int_clear;				/* 0x058 */
+	u32 wr_err_status;				/* 0x05c */
+	u32 wr_done_imwr_low;				/* 0x060 */
+	u32 wr_done_imwr_high;				/* 0x064 */
+	u32 wr_abort_imwr_low;				/* 0x068 */
+	u32 wr_abort_imwr_high;				/* 0x06c */
+	u32 wr_ch01_imwr_data;				/* 0x070 */
+	u32 wr_ch23_imwr_data;				/* 0x074 */
+	u32 wr_ch45_imwr_data;				/* 0x078 */
+	u32 wr_ch67_imwr_data;				/* 0x07c */
+	u32 padding_7[4];				/* [0x080..0x08c] */
+	u32 wr_linked_list_err_en;			/* 0x090 */
+	u32 padding_8[3];				/* [0x094..0x09c] */
+	u32 rd_int_status;				/* 0x0a0 */
+	u32 padding_9;					/* 0x0a4 */
+	u32 rd_int_mask;				/* 0x0a8 */
+	u32 rd_int_clear;				/* 0x0ac */
+	u32 padding_10;					/* 0x0b0 */
+	u32 rd_err_status_low;				/* 0x0b4 */
+	u32 rd_err_status_high;				/* 0x0b8 */
+	u32 padding_11[2];				/* [0x0bc..0x0c0] */
+	u32 rd_linked_list_err_en;			/* 0x0c4 */
+	u32 padding_12;					/* 0x0c8 */
+	u32 rd_done_imwr_low;				/* 0x0cc */
+	u32 rd_done_imwr_high;				/* 0x0d0 */
+	u32 rd_abort_imwr_low;				/* 0x0d4 */
+	u32 rd_abort_imwr_high;				/* 0x0d8 */
+	u32 rd_ch01_imwr_data;				/* 0x0dc */
+	u32 rd_ch23_imwr_data;				/* 0x0e0 */
+	u32 rd_ch45_imwr_data;				/* 0x0e4 */
+	u32 rd_ch67_imwr_data;				/* 0x0e8 */
+	u32 padding_13[4];				/* [0x0ec..0x0f8] */
+	/* eDMA channel context grouping */
+	union dw_edma_v0_type {
+		struct dw_edma_v0_legacy legacy;	/* [0x0f8..0x120] */
+		struct dw_edma_v0_unroll unroll;	/* [0x0f8..0x1120] */
+	} type;
+};
+
+struct dw_edma_v0_lli {
+	u32 control;
+	u32 transfer_size;
+	u32 sar_low;
+	u32 sar_high;
+	u32 dar_low;
+	u32 dar_high;
+};
+
+struct dw_edma_v0_llp {
+	u32 control;
+	u32 reserved;
+	u32 llp_low;
+	u32 llp_high;
+};
+
+#endif /* _DW_EDMA_V0_REGS_H */