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* [PATCH v3 0/3] dmaengine: Add support for QCOM GSI dma controller
@ 2020-09-23  6:34 Vinod Koul
  2020-09-23  6:34 ` [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding Vinod Koul
                   ` (2 more replies)
  0 siblings, 3 replies; 12+ messages in thread
From: Vinod Koul @ 2020-09-23  6:34 UTC (permalink / raw)
  To: dmaengine
  Cc: Vinod Koul, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel, Peter Ujfalusi

This series adds support for Qcom GSI dma controller found on Qualcomm SoCs.
This controller can program the peripheral configuration so we add
additional parameters in dma_slave_config for configuring the peripherals
like spi and i2c.

Changes in v3:
 - Update the i2c tre creation based on testing feedback

Changes in v2:
 - Update the binding and drop qcom specific properties
 - Move peripheral configuration as a pointer
 - Move submit queue for transactions to issue_pending

Vinod Koul (3):
  dt-bindings: dmaengine: Document qcom,gpi dma binding
  dmaengine: add peripheral configuration
  dmaengine: qcom: Add GPI dma driver

 .../devicetree/bindings/dma/qcom,gpi.yaml     |   86 +
 drivers/dma/qcom/Kconfig                      |   12 +
 drivers/dma/qcom/Makefile                     |    1 +
 drivers/dma/qcom/gpi.c                        | 2295 +++++++++++++++++
 include/dt-bindings/dma/qcom-gpi.h            |   11 +
 include/linux/dmaengine.h                     |   91 +
 6 files changed, 2496 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/dma/qcom,gpi.yaml
 create mode 100644 drivers/dma/qcom/gpi.c
 create mode 100644 include/dt-bindings/dma/qcom-gpi.h

-- 
2.26.2


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding
  2020-09-23  6:34 [PATCH v3 0/3] dmaengine: Add support for QCOM GSI dma controller Vinod Koul
@ 2020-09-23  6:34 ` Vinod Koul
  2020-09-29 18:44   ` Rob Herring
  2020-09-23  6:34 ` [PATCH v3 2/3] dmaengine: add peripheral configuration Vinod Koul
  2020-09-23  6:34 ` [PATCH v3 3/3] dmaengine: qcom: Add GPI dma driver Vinod Koul
  2 siblings, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2020-09-23  6:34 UTC (permalink / raw)
  To: dmaengine
  Cc: Vinod Koul, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel, Peter Ujfalusi

Add devicetree binding documentation for GPI DMA controller
implemented on Qualcomm SoCs

Signed-off-by: Vinod Koul <vkoul@kernel.org>
---
 .../devicetree/bindings/dma/qcom,gpi.yaml     | 86 +++++++++++++++++++
 include/dt-bindings/dma/qcom-gpi.h            | 11 +++
 2 files changed, 97 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/dma/qcom,gpi.yaml
 create mode 100644 include/dt-bindings/dma/qcom-gpi.h

diff --git a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
new file mode 100644
index 000000000000..82f404bc8745
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/qcom,gpi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Technologies Inc GPI DMA controller
+
+maintainers:
+  - Vinod Koul <vkoul@kernel.org>
+
+description: |
+  QCOM GPI DMA controller provides DMA capabilities for
+  peripheral buses such as I2C, UART, and SPI.
+
+allOf:
+  - $ref: "dma-controller.yaml#"
+
+properties:
+  compatible:
+    enum:
+      - qcom,gpi-dma
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    description:
+      Interrupt lines for each GPII instance
+    maxItems: 13
+
+  "#dma-cells":
+    const: 3
+    description: >
+      DMA clients must use the format described in dma.txt, giving a phandle
+      to the DMA controller plus the following 3 integer cells:
+      - channel: if set to 0xffffffff, any available channel will be allocated
+        for the client. Otherwise, the exact channel specified will be used.
+      - seid: serial id of the client as defined in the SoC documentation.
+      - client: type of the client as defined in dt-bindings/dma/qcom-gpi.h
+
+  iommus:
+    maxItems: 1
+
+  dma-channels:
+    maxItems: 1
+
+  dma-channel-mask:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#dma-cells"
+  - iommus
+  - dma-channels
+  - dma-channel-mask
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/dma/qcom-gpi.h>
+    gpi_dma0: dma-controller@800000 {
+        compatible = "qcom,gpi-dma";
+        #dma-cells = <3>;
+        reg = <0x00800000 0x60000>;
+        iommus = <&apps_smmu 0x0016 0x0>;
+        dma-channels = <13>;
+        dma-channel-mask = <0xfa>;
+        interrupts = <GIC_SPI 244 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 245 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 246 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 247 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 248 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 249 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 250 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 251 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 252 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 253 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 254 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 255 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 256 IRQ_TYPE_LEVEL_HIGH>;
+    };
+
+...
diff --git a/include/dt-bindings/dma/qcom-gpi.h b/include/dt-bindings/dma/qcom-gpi.h
new file mode 100644
index 000000000000..71f79eb7614c
--- /dev/null
+++ b/include/dt-bindings/dma/qcom-gpi.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2020, Linaro Ltd.  */
+
+#ifndef __DT_BINDINGS_DMA_QCOM_GPI_H__
+#define __DT_BINDINGS_DMA_QCOM_GPI_H__
+
+#define QCOM_GPI_SPI		1
+#define QCOM_GPI_UART		2
+#define QCOM_GPI_I2C		3
+
+#endif /* __DT_BINDINGS_DMA_QCOM_GPI_H__ */
-- 
2.26.2


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-09-23  6:34 [PATCH v3 0/3] dmaengine: Add support for QCOM GSI dma controller Vinod Koul
  2020-09-23  6:34 ` [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding Vinod Koul
@ 2020-09-23  6:34 ` Vinod Koul
  2020-09-29  8:06   ` Peter Ujfalusi
  2020-09-23  6:34 ` [PATCH v3 3/3] dmaengine: qcom: Add GPI dma driver Vinod Koul
  2 siblings, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2020-09-23  6:34 UTC (permalink / raw)
  To: dmaengine
  Cc: Vinod Koul, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel, Peter Ujfalusi

Some complex dmaengine controllers have capability to program the
peripheral device, so pass on the peripheral configuration as part of
dma_slave_config

Signed-off-by: Vinod Koul <vkoul@kernel.org>
---
 include/linux/dmaengine.h | 91 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 6fbd5c99e30c..bbc32271ad7f 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -380,6 +380,94 @@ enum dma_slave_buswidth {
 	DMA_SLAVE_BUSWIDTH_64_BYTES = 64,
 };
 
+/**
+ * enum spi_transfer_cmd - spi transfer commands
+ */
+enum spi_transfer_cmd {
+	SPI_TX = 1,
+	SPI_RX,
+	SPI_DUPLEX,
+};
+
+/**
+ * struct dmaengine_spi_config - spi config for peripheral
+ *
+ * @loopback_en: spi loopback enable when set
+ * @clock_pol: clock polarity
+ * @data_pol: data polarity
+ * @pack_en: process tx/rx buffers as packed
+ * @word_len: spi word length
+ * @clk_div: source clock divider
+ * @clk_src: serial clock
+ * @cmd: spi cmd
+ * @cs: chip select toggle
+ */
+struct dmaengine_spi_config {
+	u8 loopback_en;
+	u8 clock_pol;
+	u8 data_pol;
+	u8 pack_en;
+	u8 word_len;
+	u32 clk_div;
+	u32 clk_src;
+	u8 fragmentation;
+	enum spi_transfer_cmd cmd;
+	u8 cs;
+};
+
+enum i2c_op {
+	I2C_WRITE = 1,
+	I2C_READ,
+};
+
+/**
+ * struct dmaengine_i2c_config - i2c config for peripheral
+ *
+ * @pack_enable: process tx/rx buffers as packed
+ * @cycle_count: clock cycles to be sent
+ * @high_count: high period of clock
+ * @low_count: low period of clock
+ * @clk_div: source clock divider
+ * @addr: i2c bus address
+ * @stretch: stretch the clock at eot
+ * @op: i2c cmd
+ */
+struct dmaengine_i2c_config {
+	u8 pack_enable;
+	u8 cycle_count;
+	u8 high_count;
+	u8 low_count;
+	u16 clk_div;
+	u8 addr;
+	u8 stretch;
+	enum i2c_op op;
+	bool multi_msg;
+};
+
+enum dmaengine_peripheral {
+	DMAENGINE_PERIPHERAL_SPI = 1,
+	DMAENGINE_PERIPHERAL_UART = 2,
+	DMAENGINE_PERIPHERAL_I2C = 3,
+	DMAENGINE_PERIPHERAL_LAST = DMAENGINE_PERIPHERAL_I2C,
+};
+
+/**
+ * struct dmaengine_peripheral_config - peripheral configuration for
+ * dmaengine peripherals
+ *
+ * @peripheral: type of peripheral to DMA to/from
+ * @set_config: set peripheral config
+ * @rx_len: receive length for buffer
+ * @spi: peripheral config for spi
+ * @i2c: peripheral config for i2c
+ */
+struct dmaengine_peripheral_config {
+	enum dmaengine_peripheral peripheral;
+	u8 set_config;
+	u32 rx_len;
+	struct dmaengine_spi_config spi;
+	struct dmaengine_i2c_config i2c;
+};
 /**
  * struct dma_slave_config - dma slave channel runtime config
  * @direction: whether the data shall go in or out on this slave
@@ -418,6 +506,8 @@ enum dma_slave_buswidth {
  * @slave_id: Slave requester id. Only valid for slave channels. The dma
  * slave peripheral will have unique id as dma requester which need to be
  * pass as slave config.
+ * @peripheral: peripheral configuration for programming peripheral for
+ * dmaengine transfer
  *
  * This struct is passed in as configuration data to a DMA engine
  * in order to set up a certain channel for DMA transport at runtime.
@@ -443,6 +533,7 @@ struct dma_slave_config {
 	u32 dst_port_window_size;
 	bool device_fc;
 	unsigned int slave_id;
+	struct dmaengine_peripheral_config *peripheral;
 };
 
 /**
-- 
2.26.2


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH v3 3/3] dmaengine: qcom: Add GPI dma driver
  2020-09-23  6:34 [PATCH v3 0/3] dmaengine: Add support for QCOM GSI dma controller Vinod Koul
  2020-09-23  6:34 ` [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding Vinod Koul
  2020-09-23  6:34 ` [PATCH v3 2/3] dmaengine: add peripheral configuration Vinod Koul
@ 2020-09-23  6:34 ` Vinod Koul
  2 siblings, 0 replies; 12+ messages in thread
From: Vinod Koul @ 2020-09-23  6:34 UTC (permalink / raw)
  To: dmaengine
  Cc: Vinod Koul, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel, Peter Ujfalusi

This controller provides DMAengine capabilities for a variety of peripheral
buses such as I2C, UART, and SPI. By using GPI dmaengine driver, bus
drivers can use a standardize interface that is protocol independent to
transfer data between memory and peripheral.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
---
 drivers/dma/qcom/Kconfig  |   12 +
 drivers/dma/qcom/Makefile |    1 +
 drivers/dma/qcom/gpi.c    | 2295 +++++++++++++++++++++++++++++++++++++
 3 files changed, 2308 insertions(+)
 create mode 100644 drivers/dma/qcom/gpi.c

diff --git a/drivers/dma/qcom/Kconfig b/drivers/dma/qcom/Kconfig
index 3bcb689162c6..f925296b0c85 100644
--- a/drivers/dma/qcom/Kconfig
+++ b/drivers/dma/qcom/Kconfig
@@ -8,6 +8,18 @@ config QCOM_BAM_DMA
 	  Enable support for the QCOM BAM DMA controller.  This controller
 	  provides DMA capabilities for a variety of on-chip devices.
 
+config QCOM_GPI_DMA
+        tristate "Qualcomm Technologies GPI DMA support"
+        depends on ARCH_QCOM
+        select DMA_ENGINE
+        select DMA_VIRTUAL_CHANNELS
+        help
+          Enable support for the QCOM GPI DMA controller. This controller
+          provides DMA capabilities for a variety of peripheral buses such
+          as I2C, UART, and SPI. By using GPI dmaengine driver, bus drivers
+          can use a standardize interface that is protocol independent to
+          transfer data between DDR and peripheral.
+
 config QCOM_HIDMA_MGMT
 	tristate "Qualcomm Technologies HIDMA Management support"
 	select DMA_ENGINE
diff --git a/drivers/dma/qcom/Makefile b/drivers/dma/qcom/Makefile
index 1ae92da88b0c..f33f027dd0fc 100644
--- a/drivers/dma/qcom/Makefile
+++ b/drivers/dma/qcom/Makefile
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_QCOM_BAM_DMA) += bam_dma.o
+obj-$(CONFIG_QCOM_GPI_DMA) += gpi.o
 obj-$(CONFIG_QCOM_HIDMA_MGMT) += hdma_mgmt.o
 hdma_mgmt-objs	 := hidma_mgmt.o hidma_mgmt_sys.o
 obj-$(CONFIG_QCOM_HIDMA) +=  hdma.o
diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
new file mode 100644
index 000000000000..0a3b4ef6b257
--- /dev/null
+++ b/drivers/dma/qcom/gpi.c
@@ -0,0 +1,2295 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2020, Linaro Limited
+ */
+
+#include <dt-bindings/dma/qcom-gpi.h>
+#include <linux/bitfield.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/module.h>
+#include <linux/of_dma.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include "../dmaengine.h"
+#include "../virt-dma.h"
+
+#define TRE_TYPE_DMA		0x10
+#define TRE_TYPE_GO		0x20
+#define TRE_TYPE_CONFIG0	0x22
+
+/* TRE flags */
+#define TRE_FLAGS_CHAIN		BIT(0)
+#define TRE_FLAGS_IEOB		BIT(8)
+#define TRE_FLAGS_IEOT		BIT(9)
+#define TRE_FLAGS_BEI		BIT(10)
+#define TRE_FLAGS_LINK		BIT(11)
+#define TRE_FLAGS_TYPE		GENMASK(23, 16)
+
+/* SPI CONFIG0 WD0 */
+#define TRE_SPI_C0_WORD_SZ	GENMASK(4, 0)
+#define TRE_SPI_C0_LOOPBACK	BIT(8)
+#define TRE_SPI_C0_CS		BIT(11)
+#define TRE_SPI_C0_CPHA		BIT(12)
+#define TRE_SPI_C0_CPOL		BIT(13)
+#define TRE_SPI_C0_TX_PACK	BIT(24)
+#define TRE_SPI_C0_RX_PACK	BIT(25)
+
+/* CONFIG0 WD2 */
+#define TRE_C0_CLK_DIV		GENMASK(11, 0)
+#define TRE_C0_CLK_SRC		GENMASK(19, 16)
+
+/* SPI GO WD0 */
+#define TRE_SPI_GO_CMD		GENMASK(4, 0)
+#define TRE_SPI_GO_CS		GENMASK(10, 8)
+#define TRE_SPI_GO_FRAG		BIT(26)
+
+/* GO WD2 */
+#define TRE_RX_LEN		GENMASK(23, 0)
+
+/* I2C Config0 WD0 */
+#define TRE_I2C_C0_TLOW		GENMASK(7, 0)
+#define TRE_I2C_C0_THIGH	GENMASK(15, 8)
+#define TRE_I2C_C0_TCYL		GENMASK(23, 16)
+#define TRE_I2C_C0_TX_PACK	BIT(24)
+#define TRE_I2C_C0_RX_PACK      BIT(25)
+
+/* I2C GO WD0 */
+#define TRE_I2C_GO_CMD          GENMASK(4, 0)
+#define TRE_I2C_GO_ADDR		GENMASK(14, 8)
+#define TRE_I2C_GO_STRETCH	BIT(26)
+
+/* DMA TRE */
+#define TRE_DMA_LEN		GENMASK(23, 0)
+
+/* Register offsets from gpi-top */
+#define GPII_n_CH_k_CNTXT_0_OFFS(n, k)	(0x20000 + (0x4000 * (n)) + (0x80 * (k)))
+#define GPII_n_CH_k_CNTXT_0_EL_SIZE	GENMASK(31, 24)
+#define GPII_n_CH_k_CNTXT_0_CHSTATE	GENMASK(23, 20)
+#define GPII_n_CH_k_CNTXT_0_ERIDX	GENMASK(18, 14)
+#define GPII_n_CH_k_CNTXT_0_DIR		BIT(3)
+#define GPII_n_CH_k_CNTXT_0_PROTO	GENMASK(2, 0)
+
+#define GPII_n_CH_k_CNTXT_0(el_size, erindex, dir, chtype_proto)  \
+	(FIELD_PREP(GPII_n_CH_k_CNTXT_0_EL_SIZE, el_size)	| \
+	 FIELD_PREP(GPII_n_CH_k_CNTXT_0_ERIDX, erindex)		| \
+	 FIELD_PREP(GPII_n_CH_k_CNTXT_0_DIR, dir)		| \
+	 FIELD_PREP(GPII_n_CH_k_CNTXT_0_PROTO, chtype_proto))
+
+#define GPI_CHTYPE_DIR_IN	(0)
+#define GPI_CHTYPE_DIR_OUT	(1)
+
+#define GPI_CHTYPE_PROTO_GPI	(0x2)
+
+#define GPII_n_CH_k_DOORBELL_0_OFFS(n, k)	(0x22000 + (0x4000 * (n)) + (0x8 * (k)))
+#define GPII_n_CH_CMD_OFFS(n)			(0x23008 + (0x4000 * (n)))
+#define GPII_n_CH_CMD_OPCODE			GENMASK(31, 24)
+#define GPII_n_CH_CMD_CHID			GENMASK(7, 0)
+#define GPII_n_CH_CMD(opcode, chid)				 \
+		     (FIELD_PREP(GPII_n_CH_CMD_OPCODE, opcode) | \
+		      FIELD_PREP(GPII_n_CH_CMD_CHID, chid))
+
+#define GPII_n_CH_CMD_ALLOCATE		(0)
+#define GPII_n_CH_CMD_START		(1)
+#define GPII_n_CH_CMD_STOP		(2)
+#define GPII_n_CH_CMD_RESET		(9)
+#define GPII_n_CH_CMD_DE_ALLOC		(10)
+#define GPII_n_CH_CMD_UART_SW_STALE	(32)
+#define GPII_n_CH_CMD_UART_RFR_READY	(33)
+#define GPII_n_CH_CMD_UART_RFR_NOT_READY (34)
+
+/* EV Context Array */
+#define GPII_n_EV_CH_k_CNTXT_0_OFFS(n, k) (0x21000 + (0x4000 * (n)) + (0x80 * (k)))
+#define GPII_n_EV_k_CNTXT_0_EL_SIZE	GENMASK(31, 24)
+#define GPII_n_EV_k_CNTXT_0_CHSTATE	GENMASK(23, 20)
+#define GPII_n_EV_k_CNTXT_0_INTYPE	BIT(16)
+#define GPII_n_EV_k_CNTXT_0_CHTYPE	GENMASK(3, 0)
+
+#define GPII_n_EV_k_CNTXT_0(el_size, inttype, chtype)		\
+	(FIELD_PREP(GPII_n_EV_k_CNTXT_0_EL_SIZE, el_size) |	\
+	 FIELD_PREP(GPII_n_EV_k_CNTXT_0_INTYPE, inttype)  |	\
+	 FIELD_PREP(GPII_n_EV_k_CNTXT_0_CHTYPE, chtype))
+
+#define GPI_INTTYPE_IRQ		(1)
+#define GPI_CHTYPE_GPI_EV	(0x2)
+
+enum CNTXT_OFFS {
+	CNTXT_0_CONFIG = 0x0,
+	CNTXT_1_R_LENGTH = 0x4,
+	CNTXT_2_RING_BASE_LSB = 0x8,
+	CNTXT_3_RING_BASE_MSB = 0xC,
+	CNTXT_4_RING_RP_LSB = 0x10,
+	CNTXT_5_RING_RP_MSB = 0x14,
+	CNTXT_6_RING_WP_LSB = 0x18,
+	CNTXT_7_RING_WP_MSB = 0x1C,
+	CNTXT_8_RING_INT_MOD = 0x20,
+	CNTXT_9_RING_INTVEC = 0x24,
+	CNTXT_10_RING_MSI_LSB = 0x28,
+	CNTXT_11_RING_MSI_MSB = 0x2C,
+	CNTXT_12_RING_RP_UPDATE_LSB = 0x30,
+	CNTXT_13_RING_RP_UPDATE_MSB = 0x34,
+};
+
+#define GPII_n_EV_CH_k_DOORBELL_0_OFFS(n, k)	(0x22100 + (0x4000 * (n)) + (0x8 * (k)))
+#define GPII_n_EV_CH_CMD_OFFS(n)		(0x23010 + (0x4000 * (n)))
+#define GPII_n_EV_CMD_OPCODE			GENMASK(31, 24)
+#define GPII_n_EV_CMD_CHID			GENMASK(7, 0)
+#define GPII_n_EV_CMD(opcode, chid)				 \
+		     (FIELD_PREP(GPII_n_EV_CMD_OPCODE, opcode) | \
+		      FIELD_PREP(GPII_n_EV_CMD_CHID, chid))
+
+#define GPII_n_EV_CH_CMD_ALLOCATE		(0x00)
+#define GPII_n_EV_CH_CMD_RESET			(0x09)
+#define GPII_n_EV_CH_CMD_DE_ALLOC		(0x0A)
+
+#define GPII_n_CNTXT_TYPE_IRQ_OFFS(n)		(0x23080 + (0x4000 * (n)))
+
+/* mask type register */
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_OFFS(n)	(0x23088 + (0x4000 * (n)))
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_BMSK		GENMASK(6, 0)
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_GENERAL	BIT(6)
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB		BIT(3)
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_GLOB		BIT(2)
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_EV_CTRL	BIT(1)
+#define GPII_n_CNTXT_TYPE_IRQ_MSK_CH_CTRL	BIT(0)
+
+#define GPII_n_CNTXT_SRC_GPII_CH_IRQ_OFFS(n)	(0x23090 + (0x4000 * (n)))
+#define GPII_n_CNTXT_SRC_EV_CH_IRQ_OFFS(n)	(0x23094 + (0x4000 * (n)))
+
+/* Mask channel control interrupt register */
+#define GPII_n_CNTXT_SRC_CH_IRQ_MSK_OFFS(n)	(0x23098 + (0x4000 * (n)))
+#define GPII_n_CNTXT_SRC_CH_IRQ_MSK_BMSK	GENMASK(1, 0)
+
+/* Mask event control interrupt register */
+#define GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_OFFS(n)	(0x2309C + (0x4000 * (n)))
+#define GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_BMSK	BIT(0)
+
+#define GPII_n_CNTXT_SRC_CH_IRQ_CLR_OFFS(n)	(0x230A0 + (0x4000 * (n)))
+#define GPII_n_CNTXT_SRC_EV_CH_IRQ_CLR_OFFS(n)	(0x230A4 + (0x4000 * (n)))
+
+/* Mask event interrupt register */
+#define GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_OFFS(n)	(0x230B8 + (0x4000 * (n)))
+#define GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_BMSK	BIT(0)
+
+#define GPII_n_CNTXT_SRC_IEOB_IRQ_CLR_OFFS(n)	(0x230C0 + (0x4000 * (n)))
+#define GPII_n_CNTXT_GLOB_IRQ_STTS_OFFS(n)	(0x23100 + (0x4000 * (n)))
+#define GPI_GLOB_IRQ_ERROR_INT_MSK		BIT(0)
+
+/* GPII specific Global - Enable bit register */
+#define GPII_n_CNTXT_GLOB_IRQ_EN_OFFS(n)	(0x23108 + (0x4000 * (n)))
+#define GPII_n_CNTXT_GLOB_IRQ_CLR_OFFS(n)	(0x23110 + (0x4000 * (n)))
+#define GPII_n_CNTXT_GPII_IRQ_STTS_OFFS(n)	(0x23118 + (0x4000 * (n)))
+
+/* GPII general interrupt - Enable bit register */
+#define GPII_n_CNTXT_GPII_IRQ_EN_OFFS(n)	(0x23120 + (0x4000 * (n)))
+#define GPII_n_CNTXT_GPII_IRQ_EN_BMSK		GENMASK(3, 0)
+
+#define GPII_n_CNTXT_GPII_IRQ_CLR_OFFS(n)	(0x23128 + (0x4000 * (n)))
+
+/* GPII Interrupt Type register */
+#define GPII_n_CNTXT_INTSET_OFFS(n)		(0x23180 + (0x4000 * (n)))
+#define GPII_n_CNTXT_INTSET_BMSK		BIT(0)
+
+#define GPII_n_CNTXT_MSI_BASE_LSB_OFFS(n)	(0x23188 + (0x4000 * (n)))
+#define GPII_n_CNTXT_MSI_BASE_MSB_OFFS(n)	(0x2318C + (0x4000 * (n)))
+#define GPII_n_CNTXT_SCRATCH_0_OFFS(n)		(0x23400 + (0x4000 * (n)))
+#define GPII_n_CNTXT_SCRATCH_1_OFFS(n)		(0x23404 + (0x4000 * (n)))
+
+#define GPII_n_ERROR_LOG_OFFS(n)		(0x23200 + (0x4000 * (n)))
+
+/* QOS Registers */
+#define GPII_n_CH_k_QOS_OFFS(n, k)		(0x2005C + (0x4000 * (n)) + (0x80 * (k)))
+
+/* Scratch registers */
+#define GPII_n_CH_k_SCRATCH_0_OFFS(n, k)	(0x20060 + (0x4000 * (n)) + (0x80 * (k)))
+#define GPII_n_CH_k_SCRATCH_0_SEID		GENMASK(2, 0)
+#define GPII_n_CH_k_SCRATCH_0_PROTO		GENMASK(7, 4)
+#define GPII_n_CH_k_SCRATCH_0_PAIR		GENMASK(20, 16)
+#define GPII_n_CH_k_SCRATCH_0(pair, proto, seid)		\
+			     (FIELD_PREP(GPII_n_CH_k_SCRATCH_0_PAIR, pair)	| \
+			      FIELD_PREP(GPII_n_CH_k_SCRATCH_0_PROTO, proto)	| \
+			      FIELD_PREP(GPII_n_CH_k_SCRATCH_0_SEID, seid))
+#define GPII_n_CH_k_SCRATCH_1_OFFS(n, k)	(0x20064 + (0x4000 * (n)) + (0x80 * (k)))
+#define GPII_n_CH_k_SCRATCH_2_OFFS(n, k)	(0x20068 + (0x4000 * (n)) + (0x80 * (k)))
+#define GPII_n_CH_k_SCRATCH_3_OFFS(n, k)	(0x2006C + (0x4000 * (n)) + (0x80 * (k)))
+
+struct __packed gpi_tre {
+	u32 dword[4];
+};
+
+enum msm_gpi_tce_code {
+	MSM_GPI_TCE_SUCCESS = 1,
+	MSM_GPI_TCE_EOT = 2,
+	MSM_GPI_TCE_EOB = 4,
+	MSM_GPI_TCE_UNEXP_ERR = 16,
+};
+
+#define CMD_TIMEOUT_MS		(250)
+
+#define MAX_CHANNELS_PER_GPII	(2)
+#define GPI_TX_CHAN		(0)
+#define GPI_RX_CHAN		(1)
+#define STATE_IGNORE		(U32_MAX)
+#define EV_FACTOR		(2)
+#define REQ_OF_DMA_ARGS		(5) /* # of arguments required from client */
+#define CHAN_TRES		64
+
+struct __packed xfer_compl_event {
+	u64 ptr;
+	u32 length:24;
+	u8 code;
+	u16 status;
+	u8 type;
+	u8 chid;
+};
+
+struct __packed immediate_data_event {
+	u8 data_bytes[8];
+	u8 length:4;
+	u8 resvd:4;
+	u16 tre_index;
+	u8 code;
+	u16 status;
+	u8 type;
+	u8 chid;
+};
+
+struct __packed qup_notif_event {
+	u32 status;
+	u32 time;
+	u32 count:24;
+	u8 resvd;
+	u16 resvd1;
+	u8 type;
+	u8 chid;
+};
+
+struct __packed gpi_ere {
+	u32 dword[4];
+};
+
+enum GPI_EV_TYPE {
+	XFER_COMPLETE_EV_TYPE = 0x22,
+	IMMEDIATE_DATA_EV_TYPE = 0x30,
+	QUP_NOTIF_EV_TYPE = 0x31,
+	STALE_EV_TYPE = 0xFF,
+};
+
+union __packed gpi_event {
+	struct __packed xfer_compl_event xfer_compl_event;
+	struct __packed immediate_data_event immediate_data_event;
+	struct __packed qup_notif_event qup_notif_event;
+	struct __packed gpi_ere gpi_ere;
+};
+
+enum gpii_irq_settings {
+	DEFAULT_IRQ_SETTINGS,
+	MASK_IEOB_SETTINGS,
+};
+
+enum gpi_ev_state {
+	DEFAULT_EV_CH_STATE = 0,
+	EV_STATE_NOT_ALLOCATED = DEFAULT_EV_CH_STATE,
+	EV_STATE_ALLOCATED,
+	MAX_EV_STATES
+};
+
+static const char *const gpi_ev_state_str[MAX_EV_STATES] = {
+	[EV_STATE_NOT_ALLOCATED] = "NOT ALLOCATED",
+	[EV_STATE_ALLOCATED] = "ALLOCATED",
+};
+
+#define TO_GPI_EV_STATE_STR(_state) (((_state) >= MAX_EV_STATES) ? \
+				    "INVALID" : gpi_ev_state_str[(_state)])
+
+enum gpi_ch_state {
+	DEFAULT_CH_STATE = 0x0,
+	CH_STATE_NOT_ALLOCATED = DEFAULT_CH_STATE,
+	CH_STATE_ALLOCATED = 0x1,
+	CH_STATE_STARTED = 0x2,
+	CH_STATE_STOPPED = 0x3,
+	CH_STATE_STOP_IN_PROC = 0x4,
+	CH_STATE_ERROR = 0xf,
+	MAX_CH_STATES
+};
+
+enum gpi_cmd {
+	GPI_CH_CMD_BEGIN,
+	GPI_CH_CMD_ALLOCATE = GPI_CH_CMD_BEGIN,
+	GPI_CH_CMD_START,
+	GPI_CH_CMD_STOP,
+	GPI_CH_CMD_RESET,
+	GPI_CH_CMD_DE_ALLOC,
+	GPI_CH_CMD_UART_SW_STALE,
+	GPI_CH_CMD_UART_RFR_READY,
+	GPI_CH_CMD_UART_RFR_NOT_READY,
+	GPI_CH_CMD_END = GPI_CH_CMD_UART_RFR_NOT_READY,
+	GPI_EV_CMD_BEGIN,
+	GPI_EV_CMD_ALLOCATE = GPI_EV_CMD_BEGIN,
+	GPI_EV_CMD_RESET,
+	GPI_EV_CMD_DEALLOC,
+	GPI_EV_CMD_END = GPI_EV_CMD_DEALLOC,
+	GPI_MAX_CMD,
+};
+
+#define IS_CHAN_CMD(_cmd) ((_cmd) <= GPI_CH_CMD_END)
+
+static const char *const gpi_cmd_str[GPI_MAX_CMD] = {
+	[GPI_CH_CMD_ALLOCATE] = "CH ALLOCATE",
+	[GPI_CH_CMD_START] = "CH START",
+	[GPI_CH_CMD_STOP] = "CH STOP",
+	[GPI_CH_CMD_RESET] = "CH_RESET",
+	[GPI_CH_CMD_DE_ALLOC] = "DE ALLOC",
+	[GPI_CH_CMD_UART_SW_STALE] = "UART SW STALE",
+	[GPI_CH_CMD_UART_RFR_READY] = "UART RFR READY",
+	[GPI_CH_CMD_UART_RFR_NOT_READY] = "UART RFR NOT READY",
+	[GPI_EV_CMD_ALLOCATE] = "EV ALLOCATE",
+	[GPI_EV_CMD_RESET] = "EV RESET",
+	[GPI_EV_CMD_DEALLOC] = "EV DEALLOC",
+};
+
+#define TO_GPI_CMD_STR(_cmd) (((_cmd) >= GPI_MAX_CMD) ? "INVALID" : \
+				  gpi_cmd_str[(_cmd)])
+
+/*
+ * @DISABLE_STATE: no register access allowed
+ * @CONFIG_STATE:  client has configured the channel
+ * @PREP_HARDWARE: register access is allowed
+ *		   however, no processing EVENTS
+ * @ACTIVE_STATE: channels are fully operational
+ * @PREPARE_TERMINATE: graceful termination of channels
+ *		       register access is allowed
+ * @PAUSE_STATE: channels are active, but not processing any events
+ */
+enum gpi_pm_state {
+	DISABLE_STATE,
+	CONFIG_STATE,
+	PREPARE_HARDWARE,
+	ACTIVE_STATE,
+	PREPARE_TERMINATE,
+	PAUSE_STATE,
+	MAX_PM_STATE
+};
+
+#define REG_ACCESS_VALID(_pm_state) ((_pm_state) >= PREPARE_HARDWARE)
+
+static const char *const gpi_pm_state_str[MAX_PM_STATE] = {
+	[DISABLE_STATE] = "DISABLE",
+	[CONFIG_STATE] = "CONFIG",
+	[PREPARE_HARDWARE] = "PREPARE HARDWARE",
+	[ACTIVE_STATE] = "ACTIVE",
+	[PREPARE_TERMINATE] = "PREPARE TERMINATE",
+	[PAUSE_STATE] = "PAUSE",
+};
+
+#define TO_GPI_PM_STR(_state) (((_state) >= MAX_PM_STATE) ? \
+			      "INVALID" : gpi_pm_state_str[(_state)])
+
+static const struct {
+	enum gpi_cmd gpi_cmd;
+	u32 opcode;
+	u32 state;
+} gpi_cmd_info[GPI_MAX_CMD] = {
+	{
+		GPI_CH_CMD_ALLOCATE,
+		GPII_n_CH_CMD_ALLOCATE,
+		CH_STATE_ALLOCATED,
+	},
+	{
+		GPI_CH_CMD_START,
+		GPII_n_CH_CMD_START,
+		CH_STATE_STARTED,
+	},
+	{
+		GPI_CH_CMD_STOP,
+		GPII_n_CH_CMD_STOP,
+		CH_STATE_STOPPED,
+	},
+	{
+		GPI_CH_CMD_RESET,
+		GPII_n_CH_CMD_RESET,
+		CH_STATE_ALLOCATED,
+	},
+	{
+		GPI_CH_CMD_DE_ALLOC,
+		GPII_n_CH_CMD_DE_ALLOC,
+		CH_STATE_NOT_ALLOCATED,
+	},
+	{
+		GPI_CH_CMD_UART_SW_STALE,
+		GPII_n_CH_CMD_UART_SW_STALE,
+		STATE_IGNORE,
+	},
+	{
+		GPI_CH_CMD_UART_RFR_READY,
+		GPII_n_CH_CMD_UART_RFR_READY,
+		STATE_IGNORE,
+	},
+	{
+		GPI_CH_CMD_UART_RFR_NOT_READY,
+		GPII_n_CH_CMD_UART_RFR_NOT_READY,
+		STATE_IGNORE,
+	},
+	{
+		GPI_EV_CMD_ALLOCATE,
+		GPII_n_EV_CH_CMD_ALLOCATE,
+		EV_STATE_ALLOCATED,
+	},
+	{
+		GPI_EV_CMD_RESET,
+		GPII_n_EV_CH_CMD_RESET,
+		EV_STATE_ALLOCATED,
+	},
+	{
+		GPI_EV_CMD_DEALLOC,
+		GPII_n_EV_CH_CMD_DE_ALLOC,
+		EV_STATE_NOT_ALLOCATED,
+	},
+};
+
+struct gpi_ring {
+	void *pre_aligned;
+	size_t alloc_size;
+	phys_addr_t phys_addr;
+	dma_addr_t dma_handle;
+	void *base;
+	void *wp;
+	void *rp;
+	u32 len;
+	u32 el_size;
+	u32 elements;
+	bool configured;
+};
+
+struct gpi_dev {
+	struct dma_device dma_device;
+	struct device *dev;
+	struct resource *res;
+	void __iomem *regs;
+	void __iomem *ee_base; /*ee register base address*/
+	u32 max_gpii; /* maximum # of gpii instances available per gpi block */
+	u32 gpii_mask; /* gpii instances available for apps */
+	u32 ev_factor; /* ev ring length factor */
+	struct gpii *gpiis;
+};
+
+struct reg_info {
+	char *name;
+	u32 offset;
+	u32 val;
+};
+
+struct gchan {
+	struct virt_dma_chan vc;
+	u32 chid;
+	u32 seid;
+	u32 protocol;
+	struct gpii *gpii;
+	enum gpi_ch_state ch_state;
+	enum gpi_pm_state pm_state;
+	void __iomem *ch_cntxt_base_reg;
+	void __iomem *ch_cntxt_db_reg;
+	void __iomem *ch_cmd_reg;
+	u32 dir;
+	struct gpi_ring ch_ring;
+	struct dmaengine_peripheral_config config;
+};
+
+struct gpii {
+	u32 gpii_id;
+	struct gchan gchan[MAX_CHANNELS_PER_GPII];
+	struct gpi_dev *gpi_dev;
+	int irq;
+	void __iomem *regs; /* points to gpi top */
+	void __iomem *ev_cntxt_base_reg;
+	void __iomem *ev_cntxt_db_reg;
+	void __iomem *ev_ring_rp_lsb_reg;
+	void __iomem *ev_cmd_reg;
+	void __iomem *ieob_clr_reg;
+	struct mutex ctrl_lock;
+	enum gpi_ev_state ev_state;
+	bool configured_irq;
+	enum gpi_pm_state pm_state;
+	rwlock_t pm_lock;
+	struct gpi_ring ev_ring;
+	struct tasklet_struct ev_task; /* event processing tasklet */
+	struct completion cmd_completion;
+	enum gpi_cmd gpi_cmd;
+	u32 cntxt_type_irq_msk;
+	bool ieob_set;
+};
+
+#define MAX_TRE 3
+
+struct gpi_desc {
+	struct virt_dma_desc vd;
+	size_t len;
+	void *db; /* DB register to program */
+	struct gchan *gchan;
+	struct gpi_tre tre[MAX_TRE];
+	u32 num_tre;
+};
+
+static const u32 GPII_CHAN_DIR[MAX_CHANNELS_PER_GPII] = {
+	GPI_CHTYPE_DIR_OUT, GPI_CHTYPE_DIR_IN
+};
+
+static irqreturn_t gpi_handle_irq(int irq, void *data);
+static void gpi_ring_recycle_ev_element(struct gpi_ring *ring);
+static int gpi_ring_add_element(struct gpi_ring *ring, void **wp);
+static void gpi_process_events(struct gpii *gpii);
+
+static inline struct gchan *to_gchan(struct dma_chan *dma_chan)
+{
+	return container_of(dma_chan, struct gchan, vc.chan);
+}
+
+static inline struct gpi_desc *to_gpi_desc(struct virt_dma_desc *vd)
+{
+	return container_of(vd, struct gpi_desc, vd);
+}
+
+static inline phys_addr_t to_physical(const struct gpi_ring *const ring,
+				      void *addr)
+{
+	return ring->phys_addr + (addr - ring->base);
+}
+
+static inline void *to_virtual(const struct gpi_ring *const ring, phys_addr_t addr)
+{
+	return ring->base + (addr - ring->phys_addr);
+}
+
+static inline u32 gpi_read_reg(struct gpii *gpii, void __iomem *addr)
+{
+	return readl_relaxed(addr);
+}
+
+static inline void gpi_write_reg(struct gpii *gpii, void __iomem *addr, u32 val)
+{
+	writel_relaxed(val, addr);
+}
+
+/* gpi_write_reg_field - write to specific bit field */
+static inline void gpi_write_reg_field(struct gpii *gpii, void __iomem *addr,
+				       u32 mask, u32 shift, u32 val)
+{
+	u32 tmp = gpi_read_reg(gpii, addr);
+
+	tmp &= ~mask;
+	val = tmp | ((val << shift) & mask);
+	gpi_write_reg(gpii, addr, val);
+}
+
+static inline void
+gpi_update_reg(struct gpii *gpii, u32 offset, u32 mask, u32 val)
+{
+	void __iomem *addr = gpii->regs + offset;
+	u32 tmp = gpi_read_reg(gpii, addr);
+
+	tmp &= ~mask;
+	tmp |= u32_encode_bits(val, mask);
+
+	gpi_write_reg(gpii, addr, tmp);
+}
+
+static void gpi_disable_interrupts(struct gpii *gpii)
+{
+	gpi_update_reg(gpii, GPII_n_CNTXT_TYPE_IRQ_MSK_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_TYPE_IRQ_MSK_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_SRC_CH_IRQ_MSK_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_SRC_CH_IRQ_MSK_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_GLOB_IRQ_EN_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_GPII_IRQ_EN_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_GPII_IRQ_EN_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_GPII_IRQ_EN_BMSK, 0);
+	gpi_update_reg(gpii, GPII_n_CNTXT_INTSET_OFFS(gpii->gpii_id),
+		       GPII_n_CNTXT_INTSET_BMSK, 0);
+
+	gpii->cntxt_type_irq_msk = 0;
+	devm_free_irq(gpii->gpi_dev->dev, gpii->irq, gpii);
+	gpii->configured_irq = false;
+}
+
+/* configure and enable interrupts */
+static int gpi_config_interrupts(struct gpii *gpii, enum gpii_irq_settings settings, bool mask)
+{
+	const u32 enable = (GPII_n_CNTXT_TYPE_IRQ_MSK_GENERAL |
+			      GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB |
+			      GPII_n_CNTXT_TYPE_IRQ_MSK_GLOB |
+			      GPII_n_CNTXT_TYPE_IRQ_MSK_EV_CTRL |
+			      GPII_n_CNTXT_TYPE_IRQ_MSK_CH_CTRL);
+	int ret;
+
+	if (!gpii->configured_irq) {
+		ret = devm_request_irq(gpii->gpi_dev->dev, gpii->irq,
+				       gpi_handle_irq, IRQF_TRIGGER_HIGH,
+				       "gpi-dma", gpii);
+		if (ret < 0) {
+			dev_err(gpii->gpi_dev->dev, "error request irq:%d ret:%d\n",
+				gpii->irq, ret);
+			return ret;
+		}
+	}
+
+	if (settings == MASK_IEOB_SETTINGS) {
+		/*
+		 * GPII only uses one EV ring per gpii so we can globally
+		 * enable/disable IEOB interrupt
+		 */
+		if (mask)
+			gpii->cntxt_type_irq_msk |= GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB;
+		else
+			gpii->cntxt_type_irq_msk &= ~(GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB);
+		gpi_update_reg(gpii, GPII_n_CNTXT_TYPE_IRQ_MSK_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_TYPE_IRQ_MSK_BMSK, gpii->cntxt_type_irq_msk);
+	} else {
+		gpi_update_reg(gpii, GPII_n_CNTXT_TYPE_IRQ_MSK_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_TYPE_IRQ_MSK_BMSK, enable);
+		gpi_update_reg(gpii, GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_BMSK,
+			       GPII_n_CNTXT_SRC_IEOB_IRQ_MSK_BMSK);
+		gpi_update_reg(gpii, GPII_n_CNTXT_SRC_CH_IRQ_MSK_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_SRC_CH_IRQ_MSK_BMSK,
+			       GPII_n_CNTXT_SRC_CH_IRQ_MSK_BMSK);
+		gpi_update_reg(gpii, GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_BMSK,
+			       GPII_n_CNTXT_SRC_EV_CH_IRQ_MSK_BMSK);
+		gpi_update_reg(gpii, GPII_n_CNTXT_GLOB_IRQ_EN_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_GPII_IRQ_EN_BMSK,
+			       GPII_n_CNTXT_GPII_IRQ_EN_BMSK);
+		gpi_update_reg(gpii, GPII_n_CNTXT_GPII_IRQ_EN_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_GPII_IRQ_EN_BMSK, GPII_n_CNTXT_GPII_IRQ_EN_BMSK);
+		gpi_update_reg(gpii, GPII_n_CNTXT_MSI_BASE_LSB_OFFS(gpii->gpii_id), U32_MAX, 0);
+		gpi_update_reg(gpii, GPII_n_CNTXT_MSI_BASE_MSB_OFFS(gpii->gpii_id), U32_MAX, 0);
+		gpi_update_reg(gpii, GPII_n_CNTXT_SCRATCH_0_OFFS(gpii->gpii_id), U32_MAX, 0);
+		gpi_update_reg(gpii, GPII_n_CNTXT_SCRATCH_1_OFFS(gpii->gpii_id), U32_MAX, 0);
+		gpi_update_reg(gpii, GPII_n_CNTXT_INTSET_OFFS(gpii->gpii_id),
+			       GPII_n_CNTXT_INTSET_BMSK, 1);
+		gpi_update_reg(gpii, GPII_n_ERROR_LOG_OFFS(gpii->gpii_id), U32_MAX, 0);
+
+		gpii->cntxt_type_irq_msk = enable;
+	}
+
+	gpii->configured_irq = true;
+	return 0;
+}
+
+/* Sends gpii event or channel command */
+static int gpi_send_cmd(struct gpii *gpii, struct gchan *gchan,
+			enum gpi_cmd gpi_cmd)
+{
+	u32 chid = MAX_CHANNELS_PER_GPII;
+	unsigned long timeout;
+	void __iomem *cmd_reg;
+	u32 cmd;
+
+	if (gpi_cmd >= GPI_MAX_CMD)
+		return -EINVAL;
+	if (IS_CHAN_CMD(gpi_cmd))
+		chid = gchan->chid;
+
+	dev_dbg(gpii->gpi_dev->dev,
+		"sending cmd: %s:%u\n", TO_GPI_CMD_STR(gpi_cmd), chid);
+
+	/* send opcode and wait for completion */
+	reinit_completion(&gpii->cmd_completion);
+	gpii->gpi_cmd = gpi_cmd;
+
+	cmd_reg = IS_CHAN_CMD(gpi_cmd) ? gchan->ch_cmd_reg : gpii->ev_cmd_reg;
+	cmd = IS_CHAN_CMD(gpi_cmd) ? GPII_n_CH_CMD(gpi_cmd_info[gpi_cmd].opcode, chid) :
+				     GPII_n_EV_CMD(gpi_cmd_info[gpi_cmd].opcode, 0);
+	gpi_write_reg(gpii, cmd_reg, cmd);
+	timeout = wait_for_completion_timeout(&gpii->cmd_completion,
+					      msecs_to_jiffies(CMD_TIMEOUT_MS));
+	if (!timeout) {
+		dev_err(gpii->gpi_dev->dev, "cmd: %s completion timeout:%u\n",
+			TO_GPI_CMD_STR(gpi_cmd), chid);
+		return -EIO;
+	}
+
+	/* confirm new ch state is correct , if the cmd is a state change cmd */
+	if (gpi_cmd_info[gpi_cmd].state == STATE_IGNORE)
+		return 0;
+
+	if (IS_CHAN_CMD(gpi_cmd) && gchan->ch_state == gpi_cmd_info[gpi_cmd].state)
+		return 0;
+
+	if (!IS_CHAN_CMD(gpi_cmd) && gpii->ev_state == gpi_cmd_info[gpi_cmd].state)
+		return 0;
+
+	return -EIO;
+}
+
+/* program transfer ring DB register */
+static inline void gpi_write_ch_db(struct gchan *gchan,
+				   struct gpi_ring *ring, void *wp)
+{
+	struct gpii *gpii = gchan->gpii;
+	phys_addr_t p_wp;
+
+	p_wp = to_physical(ring, wp);
+	gpi_write_reg(gpii, gchan->ch_cntxt_db_reg, p_wp);
+}
+
+/* program event ring DB register */
+static inline void gpi_write_ev_db(struct gpii *gpii,
+				   struct gpi_ring *ring, void *wp)
+{
+	phys_addr_t p_wp;
+
+	p_wp = ring->phys_addr + (wp - ring->base);
+	gpi_write_reg(gpii, gpii->ev_cntxt_db_reg, p_wp);
+}
+
+/* process transfer completion interrupt */
+static void gpi_process_ieob(struct gpii *gpii)
+{
+	gpi_write_reg(gpii, gpii->ieob_clr_reg, BIT(0));
+
+	gpi_config_interrupts(gpii, MASK_IEOB_SETTINGS, 0);
+	tasklet_hi_schedule(&gpii->ev_task);
+}
+
+/* process channel control interrupt */
+static void gpi_process_ch_ctrl_irq(struct gpii *gpii)
+{
+	u32 gpii_id = gpii->gpii_id;
+	u32 offset = GPII_n_CNTXT_SRC_GPII_CH_IRQ_OFFS(gpii_id);
+	u32 ch_irq = gpi_read_reg(gpii, gpii->regs + offset);
+	struct gchan *gchan;
+	u32 chid, state;
+
+	/* clear the status */
+	offset = GPII_n_CNTXT_SRC_CH_IRQ_CLR_OFFS(gpii_id);
+	gpi_write_reg(gpii, gpii->regs + offset, (u32)ch_irq);
+
+	for (chid = 0; chid < MAX_CHANNELS_PER_GPII; chid++) {
+		if (!(BIT(chid) & ch_irq))
+			continue;
+
+		gchan = &gpii->gchan[chid];
+		state = gpi_read_reg(gpii, gchan->ch_cntxt_base_reg +
+				     CNTXT_0_CONFIG);
+		state = FIELD_GET(GPII_n_CH_k_CNTXT_0_CHSTATE, state);
+
+		/*
+		 * CH_CMD_DEALLOC cmd always successful. However cmd does
+		 * not change hardware status. So overwriting software state
+		 * to default state.
+		 */
+		if (gpii->gpi_cmd == GPI_CH_CMD_DE_ALLOC)
+			state = DEFAULT_CH_STATE;
+		gchan->ch_state = state;
+
+		/*
+		 * Triggering complete all if ch_state is not a stop in process.
+		 * Stop in process is a transition state and we will wait for
+		 * stop interrupt before notifying.
+		 */
+		if (gchan->ch_state != CH_STATE_STOP_IN_PROC)
+			complete_all(&gpii->cmd_completion);
+	}
+}
+
+/* processing gpi general error interrupts */
+static void gpi_process_gen_err_irq(struct gpii *gpii)
+{
+	u32 gpii_id = gpii->gpii_id;
+	u32 offset = GPII_n_CNTXT_GPII_IRQ_STTS_OFFS(gpii_id);
+	u32 irq_stts = gpi_read_reg(gpii, gpii->regs + offset);
+
+	/* clear the status */
+	dev_dbg(gpii->gpi_dev->dev, "irq_stts:0x%x\n", irq_stts);
+
+	/* Clear the register */
+	offset = GPII_n_CNTXT_GPII_IRQ_CLR_OFFS(gpii_id);
+	gpi_write_reg(gpii, gpii->regs + offset, irq_stts);
+}
+
+/* processing gpi level error interrupts */
+static void gpi_process_glob_err_irq(struct gpii *gpii)
+{
+	u32 gpii_id = gpii->gpii_id;
+	u32 offset = GPII_n_CNTXT_GLOB_IRQ_STTS_OFFS(gpii_id);
+	u32 irq_stts = gpi_read_reg(gpii, gpii->regs + offset);
+
+	offset = GPII_n_CNTXT_GLOB_IRQ_CLR_OFFS(gpii_id);
+	gpi_write_reg(gpii, gpii->regs + offset, irq_stts);
+
+	/* only error interrupt should be set */
+	if (irq_stts & ~GPI_GLOB_IRQ_ERROR_INT_MSK) {
+		dev_err(gpii->gpi_dev->dev, "invalid error status:0x%x\n", irq_stts);
+		return;
+	}
+
+	offset = GPII_n_ERROR_LOG_OFFS(gpii_id);
+	gpi_write_reg(gpii, gpii->regs + offset, 0);
+}
+
+/* gpii interrupt handler */
+static irqreturn_t gpi_handle_irq(int irq, void *data)
+{
+	struct gpii *gpii = data;
+	u32 gpii_id = gpii->gpii_id;
+	u32 type, offset;
+	unsigned long flags;
+
+	read_lock_irqsave(&gpii->pm_lock, flags);
+
+	/*
+	 * States are out of sync to receive interrupt
+	 * while software state is in DISABLE state, bailing out.
+	 */
+	if (!REG_ACCESS_VALID(gpii->pm_state)) {
+		dev_err(gpii->gpi_dev->dev, "receive interrupt while in %s state\n",
+			TO_GPI_PM_STR(gpii->pm_state));
+		goto exit_irq;
+	}
+
+	offset = GPII_n_CNTXT_TYPE_IRQ_OFFS(gpii->gpii_id);
+	type = gpi_read_reg(gpii, gpii->regs + offset);
+
+	do {
+		/* global gpii error */
+		if (type & GPII_n_CNTXT_TYPE_IRQ_MSK_GLOB) {
+			gpi_process_glob_err_irq(gpii);
+			type &= ~(GPII_n_CNTXT_TYPE_IRQ_MSK_GLOB);
+		}
+
+		/* transfer complete interrupt */
+		if (type & GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB) {
+			gpi_process_ieob(gpii);
+			type &= ~GPII_n_CNTXT_TYPE_IRQ_MSK_IEOB;
+		}
+
+		/* event control irq */
+		if (type & GPII_n_CNTXT_TYPE_IRQ_MSK_EV_CTRL) {
+			u32 ev_state;
+			u32 ev_ch_irq;
+
+			dev_dbg(gpii->gpi_dev->dev,
+				"processing EV CTRL interrupt\n");
+			offset = GPII_n_CNTXT_SRC_EV_CH_IRQ_OFFS(gpii_id);
+			ev_ch_irq = gpi_read_reg(gpii, gpii->regs + offset);
+
+			offset = GPII_n_CNTXT_SRC_EV_CH_IRQ_CLR_OFFS
+				(gpii_id);
+			gpi_write_reg(gpii, gpii->regs + offset, ev_ch_irq);
+			ev_state = gpi_read_reg(gpii, gpii->ev_cntxt_base_reg +
+						CNTXT_0_CONFIG);
+			ev_state = FIELD_GET(GPII_n_EV_k_CNTXT_0_CHSTATE, ev_state);
+
+			/*
+			 * CMD EV_CMD_DEALLOC is always successful. However
+			 * cmd does not change hardware status. So overwriting
+			 * software state to default state.
+			 */
+			if (gpii->gpi_cmd == GPI_EV_CMD_DEALLOC)
+				ev_state = DEFAULT_EV_CH_STATE;
+
+			gpii->ev_state = ev_state;
+			dev_dbg(gpii->gpi_dev->dev, "setting EV state to %s\n",
+				TO_GPI_EV_STATE_STR(gpii->ev_state));
+			complete_all(&gpii->cmd_completion);
+			type &= ~(GPII_n_CNTXT_TYPE_IRQ_MSK_EV_CTRL);
+		}
+
+		/* channel control irq */
+		if (type & GPII_n_CNTXT_TYPE_IRQ_MSK_CH_CTRL) {
+			dev_dbg(gpii->gpi_dev->dev, "process CH CTRL interrupts\n");
+			gpi_process_ch_ctrl_irq(gpii);
+			type &= ~(GPII_n_CNTXT_TYPE_IRQ_MSK_CH_CTRL);
+		}
+
+		if (type) {
+			dev_err(gpii->gpi_dev->dev, "Unhandled interrupt status:0x%x\n", type);
+			gpi_process_gen_err_irq(gpii);
+			goto exit_irq;
+		}
+
+		offset = GPII_n_CNTXT_TYPE_IRQ_OFFS(gpii->gpii_id);
+		type = gpi_read_reg(gpii, gpii->regs + offset);
+	} while (type);
+
+exit_irq:
+	read_unlock_irqrestore(&gpii->pm_lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+/* process DMA Immediate completion data events */
+static void gpi_process_imed_data_event(struct gchan *gchan,
+					struct immediate_data_event *imed_event)
+{
+	struct gpii *gpii = gchan->gpii;
+	struct gpi_ring *ch_ring = &gchan->ch_ring;
+	void *tre = ch_ring->base + (ch_ring->el_size * imed_event->tre_index);
+	struct dmaengine_result result;
+	struct gpi_desc *gpi_desc;
+	struct virt_dma_desc *vd;
+	unsigned long flags;
+	u32 chid;
+
+	/*
+	 * If channel not active don't process event
+	 */
+	if (gchan->pm_state != ACTIVE_STATE) {
+		dev_err(gpii->gpi_dev->dev, "skipping processing event because ch @ %s state\n",
+			TO_GPI_PM_STR(gchan->pm_state));
+		return;
+	}
+
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	vd = vchan_next_desc(&gchan->vc);
+	if (!vd) {
+		struct gpi_ere *gpi_ere;
+		struct gpi_tre *gpi_tre;
+
+		spin_unlock_irqrestore(&gchan->vc.lock, flags);
+		dev_dbg(gpii->gpi_dev->dev, "event without a pending descriptor!\n");
+		gpi_ere = (struct gpi_ere *)imed_event;
+		dev_dbg(gpii->gpi_dev->dev,
+			"Event: %08x %08x %08x %08x\n",
+			gpi_ere->dword[0], gpi_ere->dword[1],
+			gpi_ere->dword[2], gpi_ere->dword[3]);
+		gpi_tre = tre;
+		dev_dbg(gpii->gpi_dev->dev,
+			"Pending TRE: %08x %08x %08x %08x\n",
+			gpi_tre->dword[0], gpi_tre->dword[1],
+			gpi_tre->dword[2], gpi_tre->dword[3]);
+		return;
+	}
+	gpi_desc = to_gpi_desc(vd);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+
+	/*
+	 * RP pointed by Event is to last TRE processed,
+	 * we need to update ring rp to tre + 1
+	 */
+	tre += ch_ring->el_size;
+	if (tre >= (ch_ring->base + ch_ring->len))
+		tre = ch_ring->base;
+	ch_ring->rp = tre;
+
+	/* make sure rp updates are immediately visible to all cores */
+	smp_wmb();
+
+	chid = imed_event->chid;
+	if (imed_event->code == MSM_GPI_TCE_EOT && gpii->ieob_set) {
+		if (chid == GPI_RX_CHAN)
+			goto gpi_free_desc;
+		else
+			return;
+	}
+
+	if (imed_event->code == MSM_GPI_TCE_UNEXP_ERR)
+		result.result = DMA_TRANS_ABORTED;
+	else
+		result.result = DMA_TRANS_NOERROR;
+	result.residue = gpi_desc->len - imed_event->length;
+
+	dma_cookie_complete(&vd->tx);
+	dmaengine_desc_get_callback_invoke(&vd->tx, &result);
+
+gpi_free_desc:
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	list_del(&vd->node);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+	kfree(gpi_desc);
+	gpi_desc = NULL;
+}
+
+/* processing transfer completion events */
+static void gpi_process_xfer_compl_event(struct gchan *gchan,
+					 struct xfer_compl_event *compl_event)
+{
+	struct gpii *gpii = gchan->gpii;
+	struct gpi_ring *ch_ring = &gchan->ch_ring;
+	void *ev_rp = to_virtual(ch_ring, compl_event->ptr);
+	struct virt_dma_desc *vd;
+	struct gpi_desc *gpi_desc;
+	struct dmaengine_result result;
+	unsigned long flags;
+	u32 chid;
+
+	/* only process events on active channel */
+	if (unlikely(gchan->pm_state != ACTIVE_STATE)) {
+		dev_err(gpii->gpi_dev->dev, "skipping processing event because ch @ %s state\n",
+			TO_GPI_PM_STR(gchan->pm_state));
+		return;
+	}
+
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	vd = vchan_next_desc(&gchan->vc);
+	if (!vd) {
+		struct gpi_ere *gpi_ere;
+
+		spin_unlock_irqrestore(&gchan->vc.lock, flags);
+		dev_err(gpii->gpi_dev->dev, "Event without a pending descriptor!\n");
+		gpi_ere = (struct gpi_ere *)compl_event;
+		dev_err(gpii->gpi_dev->dev,
+			"Event: %08x %08x %08x %08x\n",
+			gpi_ere->dword[0], gpi_ere->dword[1],
+			gpi_ere->dword[2], gpi_ere->dword[3]);
+		return;
+	}
+
+	gpi_desc = to_gpi_desc(vd);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+
+	/*
+	 * RP pointed by Event is to last TRE processed,
+	 * we need to update ring rp to ev_rp + 1
+	 */
+	ev_rp += ch_ring->el_size;
+	if (ev_rp >= (ch_ring->base + ch_ring->len))
+		ev_rp = ch_ring->base;
+	ch_ring->rp = ev_rp;
+
+	/* update must be visible to other cores */
+	smp_wmb();
+
+	chid = compl_event->chid;
+	if (compl_event->code == MSM_GPI_TCE_EOT && gpii->ieob_set) {
+		if (chid == GPI_RX_CHAN)
+			goto gpi_free_desc;
+		else
+			return;
+	}
+
+	if (compl_event->code == MSM_GPI_TCE_UNEXP_ERR) {
+		dev_err(gpii->gpi_dev->dev, "Error in Transaction\n");
+		result.result = DMA_TRANS_ABORTED;
+	} else {
+		dev_dbg(gpii->gpi_dev->dev, "Transaction Success\n");
+		result.result = DMA_TRANS_NOERROR;
+	}
+	result.residue = gpi_desc->len - compl_event->length;
+	dev_dbg(gpii->gpi_dev->dev, "Residue %d\n", result.residue);
+
+	dma_cookie_complete(&vd->tx);
+	dmaengine_desc_get_callback_invoke(&vd->tx, &result);
+
+gpi_free_desc:
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	list_del(&vd->node);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+	kfree(gpi_desc);
+	gpi_desc = NULL;
+}
+
+/* process all events */
+static void gpi_process_events(struct gpii *gpii)
+{
+	struct gpi_ring *ev_ring = &gpii->ev_ring;
+	phys_addr_t cntxt_rp;
+	void *rp;
+	union gpi_event *gpi_event;
+	struct gchan *gchan;
+	u32 chid, type;
+
+	cntxt_rp = gpi_read_reg(gpii, gpii->ev_ring_rp_lsb_reg);
+	rp = to_virtual(ev_ring, cntxt_rp);
+
+	do {
+		while (rp != ev_ring->rp) {
+			gpi_event = ev_ring->rp;
+			chid = gpi_event->xfer_compl_event.chid;
+			type = gpi_event->xfer_compl_event.type;
+
+			dev_dbg(gpii->gpi_dev->dev,
+				"Event: CHID:%u, type:%x %08x %08x %08x %08x\n",
+				chid, type, gpi_event->gpi_ere.dword[0],
+				gpi_event->gpi_ere.dword[1], gpi_event->gpi_ere.dword[2],
+				gpi_event->gpi_ere.dword[3]);
+
+			switch (type) {
+			case XFER_COMPLETE_EV_TYPE:
+				gchan = &gpii->gchan[chid];
+				gpi_process_xfer_compl_event(gchan,
+							     &gpi_event->xfer_compl_event);
+				break;
+			case STALE_EV_TYPE:
+				dev_dbg(gpii->gpi_dev->dev, "stale event, not processing\n");
+				break;
+			case IMMEDIATE_DATA_EV_TYPE:
+				gchan = &gpii->gchan[chid];
+				gpi_process_imed_data_event(gchan,
+							    &gpi_event->immediate_data_event);
+				break;
+			case QUP_NOTIF_EV_TYPE:
+				dev_dbg(gpii->gpi_dev->dev, "QUP_NOTIF_EV_TYPE\n");
+				break;
+			default:
+				dev_dbg(gpii->gpi_dev->dev,
+					"not supported event type:0x%x\n", type);
+			}
+			gpi_ring_recycle_ev_element(ev_ring);
+		}
+		gpi_write_ev_db(gpii, ev_ring, ev_ring->wp);
+
+		/* clear pending IEOB events */
+		gpi_write_reg(gpii, gpii->ieob_clr_reg, BIT(0));
+
+		cntxt_rp = gpi_read_reg(gpii, gpii->ev_ring_rp_lsb_reg);
+		rp = to_virtual(ev_ring, cntxt_rp);
+
+	} while (rp != ev_ring->rp);
+}
+
+/* processing events using tasklet */
+static void gpi_ev_tasklet(unsigned long data)
+{
+	struct gpii *gpii = (struct gpii *)data;
+
+	read_lock_bh(&gpii->pm_lock);
+	if (!REG_ACCESS_VALID(gpii->pm_state)) {
+		read_unlock_bh(&gpii->pm_lock);
+		dev_err(gpii->gpi_dev->dev, "not processing any events, pm_state:%s\n",
+			TO_GPI_PM_STR(gpii->pm_state));
+		return;
+	}
+
+	/* process the events */
+	gpi_process_events(gpii);
+
+	/* enable IEOB, switching back to interrupts */
+	gpi_config_interrupts(gpii, MASK_IEOB_SETTINGS, 1);
+	read_unlock_bh(&gpii->pm_lock);
+}
+
+/* marks all pending events for the channel as stale */
+static void gpi_mark_stale_events(struct gchan *gchan)
+{
+	struct gpii *gpii = gchan->gpii;
+	struct gpi_ring *ev_ring = &gpii->ev_ring;
+	u32 cntxt_rp, local_rp;
+	void *ev_rp;
+
+	cntxt_rp = gpi_read_reg(gpii, gpii->ev_ring_rp_lsb_reg);
+
+	ev_rp = ev_ring->rp;
+	local_rp = (u32)to_physical(ev_ring, ev_rp);
+	while (local_rp != cntxt_rp) {
+		union gpi_event *gpi_event = ev_rp;
+		u32 chid = gpi_event->xfer_compl_event.chid;
+
+		if (chid == gchan->chid)
+			gpi_event->xfer_compl_event.type = STALE_EV_TYPE;
+		ev_rp += ev_ring->el_size;
+		if (ev_rp >= (ev_ring->base + ev_ring->len))
+			ev_rp = ev_ring->base;
+		cntxt_rp = gpi_read_reg(gpii, gpii->ev_ring_rp_lsb_reg);
+		local_rp = (u32)to_physical(ev_ring, ev_rp);
+	}
+}
+
+/* reset sw state and issue channel reset or de-alloc */
+static int gpi_reset_chan(struct gchan *gchan, enum gpi_cmd gpi_cmd)
+{
+	struct gpii *gpii = gchan->gpii;
+	struct gpi_ring *ch_ring = &gchan->ch_ring;
+	unsigned long flags;
+	LIST_HEAD(list);
+	int ret;
+
+	ret = gpi_send_cmd(gpii, gchan, gpi_cmd);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "Error with cmd:%s ret:%d\n",
+			TO_GPI_CMD_STR(gpi_cmd), ret);
+		return ret;
+	}
+
+	/* initialize the local ring ptrs */
+	ch_ring->rp = ch_ring->base;
+	ch_ring->wp = ch_ring->base;
+
+	/* visible to other cores */
+	smp_wmb();
+
+	/* check event ring for any stale events */
+	write_lock_irq(&gpii->pm_lock);
+	gpi_mark_stale_events(gchan);
+
+	/* remove all async descriptors */
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	vchan_get_all_descriptors(&gchan->vc, &list);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+	write_unlock_irq(&gpii->pm_lock);
+	vchan_dma_desc_free_list(&gchan->vc, &list);
+
+	return 0;
+}
+
+static int gpi_start_chan(struct gchan *gchan)
+{
+	struct gpii *gpii = gchan->gpii;
+	int ret;
+
+	ret = gpi_send_cmd(gpii, gchan, GPI_CH_CMD_START);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "Error with cmd:%s ret:%d\n",
+			TO_GPI_CMD_STR(GPI_CH_CMD_START), ret);
+		return ret;
+	}
+
+	/* gpii CH is active now */
+	write_lock_irq(&gpii->pm_lock);
+	gchan->pm_state = ACTIVE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+
+	return 0;
+}
+
+static int gpi_stop_chan(struct gchan *gchan)
+{
+	struct gpii *gpii = gchan->gpii;
+	int ret;
+
+	ret = gpi_send_cmd(gpii, gchan, GPI_CH_CMD_STOP);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "Error with cmd:%s ret:%d\n",
+			TO_GPI_CMD_STR(GPI_CH_CMD_STOP), ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+/* allocate and configure the transfer channel */
+static int gpi_alloc_chan(struct gchan *chan, bool send_alloc_cmd)
+{
+	struct gpii *gpii = chan->gpii;
+	struct gpi_ring *ring = &chan->ch_ring;
+	int ret;
+	u32 id = gpii->gpii_id;
+	u32 chid = chan->chid;
+	u32 pair_chid = !chid;
+
+	if (send_alloc_cmd) {
+		ret = gpi_send_cmd(gpii, chan, GPI_CH_CMD_ALLOCATE);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error with cmd:%s ret:%d\n",
+				TO_GPI_CMD_STR(GPI_CH_CMD_ALLOCATE), ret);
+			return ret;
+		}
+	}
+
+	gpi_write_reg(gpii, chan->ch_cntxt_base_reg + CNTXT_0_CONFIG,
+		      GPII_n_CH_k_CNTXT_0(ring->el_size, 0, chan->dir, GPI_CHTYPE_PROTO_GPI));
+	gpi_write_reg(gpii, chan->ch_cntxt_base_reg + CNTXT_1_R_LENGTH, ring->len);
+	gpi_write_reg(gpii, chan->ch_cntxt_base_reg + CNTXT_2_RING_BASE_LSB, ring->phys_addr);
+	gpi_write_reg(gpii, chan->ch_cntxt_base_reg + CNTXT_3_RING_BASE_MSB,
+		      upper_32_bits(ring->phys_addr));
+	gpi_write_reg(gpii, chan->ch_cntxt_db_reg + CNTXT_5_RING_RP_MSB - CNTXT_4_RING_RP_LSB,
+		      upper_32_bits(ring->phys_addr));
+	gpi_write_reg(gpii, gpii->regs + GPII_n_CH_k_SCRATCH_0_OFFS(id, chid),
+		      GPII_n_CH_k_SCRATCH_0(pair_chid, chan->protocol, chan->seid));
+	gpi_write_reg(gpii, gpii->regs + GPII_n_CH_k_SCRATCH_1_OFFS(id, chid), 0);
+	gpi_write_reg(gpii, gpii->regs + GPII_n_CH_k_SCRATCH_2_OFFS(id, chid), 0);
+	gpi_write_reg(gpii, gpii->regs + GPII_n_CH_k_SCRATCH_3_OFFS(id, chid), 0);
+	gpi_write_reg(gpii, gpii->regs + GPII_n_CH_k_QOS_OFFS(id, chid), 1);
+
+	/* flush all the writes */
+	wmb();
+	return 0;
+}
+
+/* allocate and configure event ring */
+static int gpi_alloc_ev_chan(struct gpii *gpii)
+{
+	struct gpi_ring *ring = &gpii->ev_ring;
+	void __iomem *base = gpii->ev_cntxt_base_reg;
+	int ret;
+
+	ret = gpi_send_cmd(gpii, NULL, GPI_EV_CMD_ALLOCATE);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "error with cmd:%s ret:%d\n",
+			TO_GPI_CMD_STR(GPI_EV_CMD_ALLOCATE), ret);
+		return ret;
+	}
+
+	/* program event context */
+	gpi_write_reg(gpii, base + CNTXT_0_CONFIG,
+		      GPII_n_EV_k_CNTXT_0(ring->el_size, GPI_INTTYPE_IRQ, GPI_CHTYPE_GPI_EV));
+	gpi_write_reg(gpii, base + CNTXT_1_R_LENGTH, ring->len);
+	gpi_write_reg(gpii, base + CNTXT_2_RING_BASE_LSB, lower_32_bits(ring->phys_addr));
+	gpi_write_reg(gpii, base + CNTXT_3_RING_BASE_MSB, upper_32_bits(ring->phys_addr));
+	gpi_write_reg(gpii, gpii->ev_cntxt_db_reg + CNTXT_5_RING_RP_MSB - CNTXT_4_RING_RP_LSB,
+		      upper_32_bits(ring->phys_addr));
+	gpi_write_reg(gpii, base + CNTXT_8_RING_INT_MOD, 0);
+	gpi_write_reg(gpii, base + CNTXT_10_RING_MSI_LSB, 0);
+	gpi_write_reg(gpii, base + CNTXT_11_RING_MSI_MSB, 0);
+	gpi_write_reg(gpii, base + CNTXT_8_RING_INT_MOD, 0);
+	gpi_write_reg(gpii, base + CNTXT_12_RING_RP_UPDATE_LSB, 0);
+	gpi_write_reg(gpii, base + CNTXT_13_RING_RP_UPDATE_MSB, 0);
+
+	/* add events to ring */
+	ring->wp = (ring->base + ring->len - ring->el_size);
+
+	/* flush all the writes */
+	wmb();
+
+	/* gpii is active now */
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = ACTIVE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+	gpi_write_ev_db(gpii, ring, ring->wp);
+
+	return 0;
+}
+
+/* calculate # of ERE/TRE available to queue */
+static int gpi_ring_num_elements_avail(const struct gpi_ring * const ring)
+{
+	int elements = 0;
+
+	if (ring->wp < ring->rp) {
+		elements = ((ring->rp - ring->wp) / ring->el_size) - 1;
+	} else {
+		elements = (ring->rp - ring->base) / ring->el_size;
+		elements += ((ring->base + ring->len - ring->wp) / ring->el_size) - 1;
+	}
+
+	return elements;
+}
+
+static int gpi_ring_add_element(struct gpi_ring *ring, void **wp)
+{
+	if (gpi_ring_num_elements_avail(ring) <= 0)
+		return -ENOMEM;
+
+	*wp = ring->wp;
+	ring->wp += ring->el_size;
+	if (ring->wp  >= (ring->base + ring->len))
+		ring->wp = ring->base;
+
+	/* visible to other cores */
+	smp_wmb();
+
+	return 0;
+}
+
+static void gpi_ring_recycle_ev_element(struct gpi_ring *ring)
+{
+	/* Update the WP */
+	ring->wp += ring->el_size;
+	if (ring->wp  >= (ring->base + ring->len))
+		ring->wp = ring->base;
+
+	/* Update the RP */
+	ring->rp += ring->el_size;
+	if (ring->rp  >= (ring->base + ring->len))
+		ring->rp = ring->base;
+
+	/* visible to other cores */
+	smp_wmb();
+}
+
+static void gpi_free_ring(struct gpi_ring *ring,
+			  struct gpii *gpii)
+{
+	dma_free_coherent(gpii->gpi_dev->dev, ring->alloc_size,
+			  ring->pre_aligned, ring->dma_handle);
+	memset(ring, 0, sizeof(*ring));
+}
+
+/* allocate memory for transfer and event rings */
+static int gpi_alloc_ring(struct gpi_ring *ring, u32 elements,
+			  u32 el_size, struct gpii *gpii)
+{
+	u64 len = elements * el_size;
+	int bit;
+
+	/* ring len must be power of 2 */
+	bit = find_last_bit((unsigned long *)&len, 32);
+	if (((1 << bit) - 1) & len)
+		bit++;
+	len = 1 << bit;
+	ring->alloc_size = (len + (len - 1));
+	dev_dbg(gpii->gpi_dev->dev,
+		"#el:%u el_size:%u len:%u actual_len:%llu alloc_size:%lu\n",
+		  elements, el_size, (elements * el_size), len,
+		  ring->alloc_size);
+
+	ring->pre_aligned = dma_alloc_coherent(gpii->gpi_dev->dev,
+					       ring->alloc_size,
+					       &ring->dma_handle, GFP_KERNEL);
+	if (!ring->pre_aligned) {
+		dev_err(gpii->gpi_dev->dev, "could not alloc size:%lu mem for ring\n",
+			ring->alloc_size);
+		return -ENOMEM;
+	}
+
+	/* align the physical mem */
+	ring->phys_addr = (ring->dma_handle + (len - 1)) & ~(len - 1);
+	ring->base = ring->pre_aligned + (ring->phys_addr - ring->dma_handle);
+	ring->rp = ring->base;
+	ring->wp = ring->base;
+	ring->len = len;
+	ring->el_size = el_size;
+	ring->elements = ring->len / ring->el_size;
+	memset(ring->base, 0, ring->len);
+	ring->configured = true;
+
+	/* update to other cores */
+	smp_wmb();
+
+	dev_dbg(gpii->gpi_dev->dev,
+		"phy_pre:0x%0llx phy_alig:0x%0llx len:%u el_size:%u elements:%u\n",
+		ring->dma_handle, ring->phys_addr, ring->len,
+		ring->el_size, ring->elements);
+
+	return 0;
+}
+
+/* copy tre into transfer ring */
+static void gpi_queue_xfer(struct gpii *gpii, struct gchan *gchan,
+			   struct gpi_tre *gpi_tre, void **wp)
+{
+	struct gpi_tre *ch_tre;
+	int ret;
+
+	/* get next tre location we can copy */
+	ret = gpi_ring_add_element(&gchan->ch_ring, (void **)&ch_tre);
+	if (unlikely(ret)) {
+		dev_err(gpii->gpi_dev->dev, "Error adding ring element to xfer ring\n");
+		return;
+	}
+
+	/* copy the tre info */
+	memcpy(ch_tre, gpi_tre, sizeof(*ch_tre));
+	*wp = ch_tre;
+}
+
+/* reset and restart transfer channel */
+static int gpi_terminate_all(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	int schid, echid, i;
+	int ret = 0;
+
+	mutex_lock(&gpii->ctrl_lock);
+
+	/*
+	 * treat both channels as a group if its protocol is not UART
+	 * STOP, RESET, or START needs to be in lockstep
+	 */
+	schid = (gchan->protocol == QCOM_GPI_UART) ? gchan->chid : 0;
+	echid = (gchan->protocol == QCOM_GPI_UART) ? schid + 1 : MAX_CHANNELS_PER_GPII;
+
+	/* stop the channel */
+	for (i = schid; i < echid; i++) {
+		gchan = &gpii->gchan[i];
+
+		/* disable ch state so no more TRE processing */
+		write_lock_irq(&gpii->pm_lock);
+		gchan->pm_state = PREPARE_TERMINATE;
+		write_unlock_irq(&gpii->pm_lock);
+
+		/* send command to Stop the channel */
+		ret = gpi_stop_chan(gchan);
+	}
+
+	/* reset the channels (clears any pending tre) */
+	for (i = schid; i < echid; i++) {
+		gchan = &gpii->gchan[i];
+
+		ret = gpi_reset_chan(gchan, GPI_CH_CMD_RESET);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error resetting channel ret:%d\n", ret);
+			goto terminate_exit;
+		}
+
+		/* reprogram channel CNTXT */
+		ret = gpi_alloc_chan(gchan, false);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error alloc_channel ret:%d\n", ret);
+			goto terminate_exit;
+		}
+	}
+
+	/* restart the channels */
+	for (i = schid; i < echid; i++) {
+		gchan = &gpii->gchan[i];
+
+		ret = gpi_start_chan(gchan);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error Starting Channel ret:%d\n", ret);
+			goto terminate_exit;
+		}
+	}
+
+terminate_exit:
+	mutex_unlock(&gpii->ctrl_lock);
+	return ret;
+}
+
+/* pause dma transfer for all channels */
+static int gpi_pause(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	int i, ret;
+
+	mutex_lock(&gpii->ctrl_lock);
+
+	/*
+	 * pause/resume are per gpii not per channel, so
+	 * client needs to call pause only once
+	 */
+	if (gpii->pm_state == PAUSE_STATE) {
+		dev_dbg(gpii->gpi_dev->dev, "channel is already paused\n");
+		mutex_unlock(&gpii->ctrl_lock);
+		return 0;
+	}
+
+	/* send stop command to stop the channels */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++) {
+		ret = gpi_stop_chan(&gpii->gchan[i]);
+		if (ret) {
+			mutex_unlock(&gpii->ctrl_lock);
+			return ret;
+		}
+	}
+
+	disable_irq(gpii->irq);
+
+	/* Wait for threads to complete out */
+	tasklet_kill(&gpii->ev_task);
+
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = PAUSE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+	mutex_unlock(&gpii->ctrl_lock);
+
+	return 0;
+}
+
+/* resume dma transfer */
+static int gpi_resume(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	int i, ret;
+
+	mutex_lock(&gpii->ctrl_lock);
+	if (gpii->pm_state == ACTIVE_STATE) {
+		dev_dbg(gpii->gpi_dev->dev, "channel is already active\n");
+		mutex_unlock(&gpii->ctrl_lock);
+		return 0;
+	}
+
+	enable_irq(gpii->irq);
+
+	/* send start command to start the channels */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++) {
+		ret = gpi_send_cmd(gpii, &gpii->gchan[i], GPI_CH_CMD_START);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error starting chan, ret:%d\n", ret);
+			mutex_unlock(&gpii->ctrl_lock);
+			return ret;
+		}
+	}
+
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = ACTIVE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+	mutex_unlock(&gpii->ctrl_lock);
+
+	return 0;
+}
+
+static void gpi_desc_free(struct virt_dma_desc *vd)
+{
+	struct gpi_desc *gpi_desc = to_gpi_desc(vd);
+
+	kfree(gpi_desc);
+	gpi_desc = NULL;
+}
+
+static int
+gpi_peripheral_config(struct dma_chan *chan, struct dma_slave_config *config)
+{
+	struct gchan *gchan = to_gchan(chan);
+
+	if (!config->peripheral)
+		return -EINVAL;
+
+	memcpy(&gchan->config, config->peripheral, sizeof(gchan->config));
+
+	return 0;
+}
+
+static int gpi_create_i2c_tre(struct gchan *chan, struct gpi_desc *desc,
+			      struct scatterlist *sgl, enum dma_transfer_direction direction)
+{
+	struct dmaengine_i2c_config *i2c = &chan->config.i2c;
+	struct device *dev = chan->gpii->gpi_dev->dev;
+	unsigned int tre_idx = 0;
+	dma_addr_t address;
+	struct gpi_tre *tre;
+	unsigned int i;
+
+	/* first create config tre if applicable */
+	if (chan->config.set_config) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		tre->dword[0] = u32_encode_bits(i2c->low_count, TRE_I2C_C0_TLOW);
+		tre->dword[0] |= u32_encode_bits(i2c->high_count, TRE_I2C_C0_THIGH);
+		tre->dword[0] |= u32_encode_bits(i2c->cycle_count, TRE_I2C_C0_TCYL);
+		tre->dword[0] |= u32_encode_bits(i2c->pack_enable, TRE_I2C_C0_TX_PACK);
+		tre->dword[0] |= u32_encode_bits(i2c->pack_enable, TRE_I2C_C0_RX_PACK);
+
+		tre->dword[1] = 0;
+
+		tre->dword[2] = u32_encode_bits(i2c->clk_div, TRE_C0_CLK_DIV);
+
+		tre->dword[3] = u32_encode_bits(TRE_TYPE_CONFIG0, TRE_FLAGS_TYPE);
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
+	}
+
+	/* create the GO tre for Tx */
+	if (i2c->op == I2C_WRITE) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		if (i2c->multi_msg)
+			tre->dword[0] = u32_encode_bits(I2C_READ, TRE_I2C_GO_CMD);
+		else
+			tre->dword[0] = u32_encode_bits(i2c->op, TRE_I2C_GO_CMD);
+
+		tre->dword[0] |= u32_encode_bits(i2c->addr, TRE_I2C_GO_ADDR);
+		tre->dword[0] |= u32_encode_bits(i2c->stretch, TRE_I2C_GO_STRETCH);
+
+		tre->dword[1] = 0;
+		tre->dword[2] = u32_encode_bits(chan->config.rx_len, TRE_RX_LEN);
+
+		tre->dword[3] = u32_encode_bits(TRE_TYPE_GO, TRE_FLAGS_TYPE);
+
+		if (i2c->multi_msg)
+			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_LINK);
+		else
+			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
+	}
+
+	if (i2c->op == I2C_READ || i2c->multi_msg == false) {
+		/* create the DMA TRE */
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		address = sg_dma_address(sgl);
+		tre->dword[0] = lower_32_bits(address);
+		tre->dword[1] = upper_32_bits(address);
+
+		tre->dword[2] = u32_encode_bits(sg_dma_len(sgl), TRE_DMA_LEN);
+
+		tre->dword[3] = u32_encode_bits(TRE_TYPE_DMA, TRE_FLAGS_TYPE);
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOT);
+	};
+
+	for (i = 0; i < tre_idx; i++)
+		dev_dbg(dev, "TRE:%d %x:%x:%x:%x\n", i, desc->tre[i].dword[0],
+			desc->tre[i].dword[1], desc->tre[i].dword[2], desc->tre[i].dword[3]);
+
+	return tre_idx;
+}
+
+static int gpi_create_spi_tre(struct gchan *chan, struct gpi_desc *desc,
+			      struct scatterlist *sgl, enum dma_transfer_direction direction)
+{
+	struct dmaengine_spi_config *spi = &chan->config.spi;
+	struct device *dev = chan->gpii->gpi_dev->dev;
+	unsigned int tre_idx = 0;
+	dma_addr_t address;
+	struct gpi_tre *tre;
+	unsigned int i;
+
+	/* first create config tre if applicable */
+	if (direction == DMA_MEM_TO_DEV && chan->config.set_config) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		tre->dword[0] = u32_encode_bits(spi->word_len, TRE_SPI_C0_WORD_SZ);
+		tre->dword[0] |= u32_encode_bits(spi->loopback_en, TRE_SPI_C0_LOOPBACK);
+		tre->dword[0] |= u32_encode_bits(spi->clock_pol, TRE_SPI_C0_CPOL);
+		tre->dword[0] |= u32_encode_bits(spi->data_pol, TRE_SPI_C0_CPHA);
+		tre->dword[0] |= u32_encode_bits(spi->pack_en, TRE_SPI_C0_TX_PACK);
+		tre->dword[0] |= u32_encode_bits(spi->pack_en, TRE_SPI_C0_RX_PACK);
+
+		tre->dword[1] = 0;
+
+		tre->dword[2] = u32_encode_bits(spi->clk_div, TRE_C0_CLK_DIV);
+		tre->dword[2] |= u32_encode_bits(spi->clk_src, TRE_C0_CLK_SRC);
+
+		tre->dword[3] = u32_encode_bits(TRE_TYPE_CONFIG0, TRE_FLAGS_TYPE);
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
+	}
+
+	/* create the GO tre for Tx */
+	if (direction == DMA_MEM_TO_DEV) {
+		tre = &desc->tre[tre_idx];
+		tre_idx++;
+
+		tre->dword[0] = u32_encode_bits(spi->fragmentation, TRE_SPI_GO_FRAG);
+		tre->dword[0] |= u32_encode_bits(spi->cs, TRE_SPI_GO_CS);
+		tre->dword[0] |= u32_encode_bits(spi->cmd, TRE_SPI_GO_CMD);
+
+		tre->dword[1] = 0;
+
+		tre->dword[2] = u32_encode_bits(chan->config.rx_len, TRE_RX_LEN);
+
+		tre->dword[3] = u32_encode_bits(TRE_TYPE_GO, TRE_FLAGS_TYPE);
+		if (spi->cmd == SPI_RX)
+			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOB);
+		else
+			tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
+	}
+
+	/* create the dma tre */
+	tre = &desc->tre[tre_idx];
+	tre_idx++;
+
+	address = sg_dma_address(sgl);
+	tre->dword[0] = lower_32_bits(address);
+	tre->dword[1] = upper_32_bits(address);
+
+	tre->dword[2] = u32_encode_bits(sg_dma_len(sgl), TRE_DMA_LEN);
+
+	tre->dword[3] = u32_encode_bits(TRE_TYPE_DMA, TRE_FLAGS_TYPE);
+	if (direction == DMA_MEM_TO_DEV)
+		tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOT);
+
+	for (i = 0; i < tre_idx; i++)
+		dev_dbg(dev, "TRE:%d %x:%x:%x:%x\n", i, desc->tre[i].dword[0],
+			desc->tre[i].dword[1], desc->tre[i].dword[2], desc->tre[i].dword[3]);
+
+	return tre_idx;
+}
+
+/* copy tre into transfer ring */
+static struct dma_async_tx_descriptor *
+gpi_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
+		  unsigned int sg_len, enum dma_transfer_direction direction,
+		  unsigned long flags, void *context)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	struct device *dev = gpii->gpi_dev->dev;
+	struct gpi_ring *ch_ring = &gchan->ch_ring;
+	struct gpi_desc *gpi_desc;
+	u32 nr, nr_tre = 0;
+	int i;
+
+	gpii->ieob_set = false;
+	if (!is_slave_direction(direction)) {
+		dev_err(gpii->gpi_dev->dev, "invalid dma direction: %d\n", direction);
+		return NULL;
+	}
+
+	if (sg_len > 1) {
+		dev_err(dev, "Multi sg sent, we support only one atm: %d\n", sg_len);
+		return NULL;
+	}
+
+	nr_tre = 3;
+	if (!gchan->config.set_config)
+		nr_tre = 2;
+	if (direction == DMA_DEV_TO_MEM) /* rx */
+		nr_tre = 1;
+
+	/* calculate # of elements required & available */
+	nr = gpi_ring_num_elements_avail(ch_ring);
+	if (nr < nr_tre) {
+		dev_err(dev, "not enough space in ring, avail:%u required:%u\n", nr, nr_tre);
+		return NULL;
+	}
+
+	gpi_desc = kzalloc(sizeof(*gpi_desc), GFP_NOWAIT);
+	if (!gpi_desc)
+		return NULL;
+
+	/* create TREs for xfer */
+	if (gchan->config.peripheral == DMAENGINE_PERIPHERAL_SPI) {
+		i = gpi_create_spi_tre(gchan, gpi_desc, sgl, direction);
+	} else if (gchan->config.peripheral == DMAENGINE_PERIPHERAL_I2C) {
+		i = gpi_create_i2c_tre(gchan, gpi_desc, sgl, direction);
+	} else {
+		dev_err(dev, "invalid peripheral: %d\n", gchan->config.peripheral);
+		kfree(gpi_desc);
+		return NULL;
+	}
+
+	/* set up the descriptor */
+	gpi_desc->gchan = gchan;
+	gpi_desc->len = sg_dma_len(sgl);
+	gpi_desc->num_tre  = i;
+
+	return vchan_tx_prep(&gchan->vc, &gpi_desc->vd, flags);
+}
+
+/* rings transfer ring db to being transfer */
+static void gpi_issue_pending(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	unsigned long flags, pm_lock_flags;
+	struct virt_dma_desc *vd = NULL;
+	struct gpi_desc *gpi_desc;
+	struct gpi_ring *ch_ring = &gchan->ch_ring;
+	void *tre, *wp = NULL;
+	int i;
+
+	read_lock_irqsave(&gpii->pm_lock, pm_lock_flags);
+
+	/* move all submitted discriptors to issued list */
+	spin_lock_irqsave(&gchan->vc.lock, flags);
+	if (vchan_issue_pending(&gchan->vc))
+		vd = list_last_entry(&gchan->vc.desc_issued,
+				     struct virt_dma_desc, node);
+	spin_unlock_irqrestore(&gchan->vc.lock, flags);
+
+	/* nothing to do list is empty */
+	if (!vd) {
+		read_unlock_irqrestore(&gpii->pm_lock, pm_lock_flags);
+		return;
+	}
+
+	gpi_desc = to_gpi_desc(vd);
+	for (i = 0; i < gpi_desc->num_tre; i++) {
+		tre = &gpi_desc->tre[i];
+		gpi_queue_xfer(gpii, gchan, tre, &wp);
+	}
+
+	gpi_desc->db = ch_ring->wp;
+	gpi_write_ch_db(gchan, &gchan->ch_ring, gpi_desc->db);
+	read_unlock_irqrestore(&gpii->pm_lock, pm_lock_flags);
+}
+
+static int gpi_ch_init(struct gchan *gchan)
+{
+	struct gpii *gpii = gchan->gpii;
+	const int ev_factor = gpii->gpi_dev->ev_factor;
+	u32 elements;
+	int i = 0, ret = 0;
+
+	gchan->pm_state = CONFIG_STATE;
+
+	/* check if both channels are configured before continue */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++)
+		if (gpii->gchan[i].pm_state != CONFIG_STATE)
+			goto exit_gpi_init;
+
+	/* protocol must be same for both channels */
+	if (gpii->gchan[0].protocol != gpii->gchan[1].protocol) {
+		dev_err(gpii->gpi_dev->dev, "protocol did not match protocol %u != %u\n",
+			gpii->gchan[0].protocol, gpii->gchan[1].protocol);
+		ret = -EINVAL;
+		goto exit_gpi_init;
+	}
+
+	/* allocate memory for event ring */
+	elements = CHAN_TRES << ev_factor;
+	ret = gpi_alloc_ring(&gpii->ev_ring, elements,
+			     sizeof(union gpi_event), gpii);
+	if (ret)
+		goto exit_gpi_init;
+
+	/* configure interrupts */
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = PREPARE_HARDWARE;
+	write_unlock_irq(&gpii->pm_lock);
+	ret = gpi_config_interrupts(gpii, DEFAULT_IRQ_SETTINGS, 0);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "error config. interrupts, ret:%d\n", ret);
+		goto error_config_int;
+	}
+
+	/* allocate event rings */
+	ret = gpi_alloc_ev_chan(gpii);
+	if (ret) {
+		dev_err(gpii->gpi_dev->dev, "error alloc_ev_chan:%d\n", ret);
+		goto error_alloc_ev_ring;
+	}
+
+	/* Allocate all channels */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++) {
+		ret = gpi_alloc_chan(&gpii->gchan[i], true);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error allocating chan:%d\n", ret);
+			goto error_alloc_chan;
+		}
+	}
+
+	/* start channels  */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++) {
+		ret = gpi_start_chan(&gpii->gchan[i]);
+		if (ret) {
+			dev_err(gpii->gpi_dev->dev, "Error start chan:%d\n", ret);
+			goto error_start_chan;
+		}
+	}
+	return ret;
+
+error_start_chan:
+	for (i = i - 1; i >= 0; i++) {
+		gpi_stop_chan(&gpii->gchan[i]);
+		gpi_send_cmd(gpii, gchan, GPI_CH_CMD_RESET);
+	}
+	i = 2;
+error_alloc_chan:
+	for (i = i - 1; i >= 0; i--)
+		gpi_reset_chan(gchan, GPI_CH_CMD_DE_ALLOC);
+error_alloc_ev_ring:
+	gpi_disable_interrupts(gpii);
+error_config_int:
+	gpi_free_ring(&gpii->ev_ring, gpii);
+exit_gpi_init:
+	mutex_unlock(&gpii->ctrl_lock);
+	return ret;
+}
+
+/* release all channel resources */
+static void gpi_free_chan_resources(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	enum gpi_pm_state cur_state;
+	int ret, i;
+
+	mutex_lock(&gpii->ctrl_lock);
+
+	cur_state = gchan->pm_state;
+
+	/* disable ch state so no more TRE processing for this channel */
+	write_lock_irq(&gpii->pm_lock);
+	gchan->pm_state = PREPARE_TERMINATE;
+	write_unlock_irq(&gpii->pm_lock);
+
+	/* attempt to do graceful hardware shutdown */
+	if (cur_state == ACTIVE_STATE) {
+		gpi_stop_chan(gchan);
+
+		ret = gpi_send_cmd(gpii, gchan, GPI_CH_CMD_RESET);
+		if (ret)
+			dev_err(gpii->gpi_dev->dev, "error resetting channel:%d\n", ret);
+
+		gpi_reset_chan(gchan, GPI_CH_CMD_DE_ALLOC);
+	}
+
+	/* free all allocated memory */
+	gpi_free_ring(&gchan->ch_ring, gpii);
+	vchan_free_chan_resources(&gchan->vc);
+
+	write_lock_irq(&gpii->pm_lock);
+	gchan->pm_state = DISABLE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+
+	/* if other rings are still active exit */
+	for (i = 0; i < MAX_CHANNELS_PER_GPII; i++)
+		if (gpii->gchan[i].ch_ring.configured)
+			goto exit_free;
+
+	/* deallocate EV Ring */
+	cur_state = gpii->pm_state;
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = PREPARE_TERMINATE;
+	write_unlock_irq(&gpii->pm_lock);
+
+	/* wait for threads to complete out */
+	tasklet_kill(&gpii->ev_task);
+
+	/* send command to de allocate event ring */
+	if (cur_state == ACTIVE_STATE)
+		gpi_send_cmd(gpii, NULL, GPI_EV_CMD_DEALLOC);
+
+	gpi_free_ring(&gpii->ev_ring, gpii);
+
+	/* disable interrupts */
+	if (cur_state == ACTIVE_STATE)
+		gpi_disable_interrupts(gpii);
+
+	/* set final state to disable */
+	write_lock_irq(&gpii->pm_lock);
+	gpii->pm_state = DISABLE_STATE;
+	write_unlock_irq(&gpii->pm_lock);
+
+exit_free:
+	mutex_unlock(&gpii->ctrl_lock);
+}
+
+/* allocate channel resources */
+static int gpi_alloc_chan_resources(struct dma_chan *chan)
+{
+	struct gchan *gchan = to_gchan(chan);
+	struct gpii *gpii = gchan->gpii;
+	int ret;
+
+	mutex_lock(&gpii->ctrl_lock);
+
+	/* allocate memory for transfer ring */
+	ret = gpi_alloc_ring(&gchan->ch_ring, CHAN_TRES,
+			     sizeof(struct gpi_tre), gpii);
+	if (ret)
+		goto xfer_alloc_err;
+
+	ret = gpi_ch_init(gchan);
+
+	mutex_unlock(&gpii->ctrl_lock);
+
+	return ret;
+xfer_alloc_err:
+	mutex_unlock(&gpii->ctrl_lock);
+
+	return ret;
+}
+
+static int gpi_find_avail_gpii(struct gpi_dev *gpi_dev, u32 seid)
+{
+	struct gchan *tx_chan, *rx_chan;
+	unsigned int gpii;
+
+	/* check if same seid is already configured for another chid */
+	for (gpii = 0; gpii < gpi_dev->max_gpii; gpii++) {
+		if (!((1 << gpii) & gpi_dev->gpii_mask))
+			continue;
+
+		tx_chan = &gpi_dev->gpiis[gpii].gchan[GPI_TX_CHAN];
+		rx_chan = &gpi_dev->gpiis[gpii].gchan[GPI_RX_CHAN];
+
+		if (rx_chan->vc.chan.client_count && rx_chan->seid == seid)
+			return gpii;
+		if (tx_chan->vc.chan.client_count && tx_chan->seid == seid)
+			return gpii;
+	}
+
+	/* no channels configured with same seid, return next avail gpii */
+	for (gpii = 0; gpii < gpi_dev->max_gpii; gpii++) {
+		if (!((1 << gpii) & gpi_dev->gpii_mask))
+			continue;
+
+		tx_chan = &gpi_dev->gpiis[gpii].gchan[GPI_TX_CHAN];
+		rx_chan = &gpi_dev->gpiis[gpii].gchan[GPI_RX_CHAN];
+
+		/* check if gpii is configured */
+		if (tx_chan->vc.chan.client_count ||
+		    rx_chan->vc.chan.client_count)
+			continue;
+
+		/* found a free gpii */
+		return gpii;
+	}
+
+	/* no gpii instance available to use */
+	return -EIO;
+}
+
+/* gpi_of_dma_xlate: open client requested channel */
+static struct dma_chan *gpi_of_dma_xlate(struct of_phandle_args *args,
+					 struct of_dma *of_dma)
+{
+	struct gpi_dev *gpi_dev = (struct gpi_dev *)of_dma->of_dma_data;
+	u32 seid, chid;
+	int gpii;
+	struct gchan *gchan;
+
+	if (args->args_count < 3) {
+		dev_err(gpi_dev->dev, "gpii require minimum 2 args, client passed:%d args\n",
+			args->args_count);
+		return NULL;
+	}
+
+	chid = args->args[0];
+	if (chid >= MAX_CHANNELS_PER_GPII) {
+		dev_err(gpi_dev->dev, "gpii channel:%d not valid\n", chid);
+		return NULL;
+	}
+
+	seid = args->args[1];
+
+	/* find next available gpii to use */
+	gpii = gpi_find_avail_gpii(gpi_dev, seid);
+	if (gpii < 0) {
+		dev_err(gpi_dev->dev, "no available gpii instances\n");
+		return NULL;
+	}
+
+	gchan = &gpi_dev->gpiis[gpii].gchan[chid];
+	if (gchan->vc.chan.client_count) {
+		dev_err(gpi_dev->dev, "gpii:%d chid:%d seid:%d already configured\n",
+			gpii, chid, gchan->seid);
+		return NULL;
+	}
+
+	gchan->seid = seid;
+	gchan->protocol = args->args[2];
+
+	return dma_get_slave_channel(&gchan->vc.chan);
+}
+
+static int gpi_probe(struct platform_device *pdev)
+{
+	struct gpi_dev *gpi_dev;
+	unsigned int i;
+	int ret;
+
+	gpi_dev = devm_kzalloc(&pdev->dev, sizeof(*gpi_dev), GFP_KERNEL);
+	if (!gpi_dev)
+		return -ENOMEM;
+
+	gpi_dev->dev = &pdev->dev;
+	gpi_dev->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	gpi_dev->regs = devm_ioremap_resource(gpi_dev->dev, gpi_dev->res);
+	if (IS_ERR(gpi_dev->regs))
+		return PTR_ERR(gpi_dev->regs);
+	gpi_dev->ee_base = gpi_dev->regs;
+
+	ret = of_property_read_u32(gpi_dev->dev->of_node, "dma-channels",
+				   &gpi_dev->max_gpii);
+	if (ret) {
+		dev_err(gpi_dev->dev, "missing 'max-no-gpii' DT node\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(gpi_dev->dev->of_node, "dma-channel-mask",
+				   &gpi_dev->gpii_mask);
+	if (ret) {
+		dev_err(gpi_dev->dev, "missing 'gpii-mask' DT node\n");
+		return ret;
+	}
+
+	gpi_dev->ev_factor = EV_FACTOR;
+
+	ret = dma_set_mask(gpi_dev->dev, DMA_BIT_MASK(64));
+	if (ret) {
+		dev_err(gpi_dev->dev, "Error setting dma_mask to 64, ret:%d\n", ret);
+		return ret;
+	}
+
+	gpi_dev->gpiis = devm_kzalloc(gpi_dev->dev, sizeof(*gpi_dev->gpiis) *
+				      gpi_dev->max_gpii, GFP_KERNEL);
+	if (!gpi_dev->gpiis)
+		return -ENOMEM;
+
+	/* setup all the supported gpii */
+	INIT_LIST_HEAD(&gpi_dev->dma_device.channels);
+	for (i = 0; i < gpi_dev->max_gpii; i++) {
+		struct gpii *gpii = &gpi_dev->gpiis[i];
+		int chan;
+
+		if (!((1 << i) & gpi_dev->gpii_mask))
+			continue;
+
+		/* set up ev cntxt register map */
+		gpii->ev_cntxt_base_reg = gpi_dev->ee_base + GPII_n_EV_CH_k_CNTXT_0_OFFS(i, 0);
+		gpii->ev_cntxt_db_reg = gpi_dev->ee_base + GPII_n_EV_CH_k_DOORBELL_0_OFFS(i, 0);
+		gpii->ev_ring_rp_lsb_reg = gpii->ev_cntxt_base_reg + CNTXT_4_RING_RP_LSB;
+		gpii->ev_cmd_reg = gpi_dev->ee_base + GPII_n_EV_CH_CMD_OFFS(i);
+		gpii->ieob_clr_reg = gpi_dev->ee_base + GPII_n_CNTXT_SRC_IEOB_IRQ_CLR_OFFS(i);
+
+		/* set up irq */
+		ret = platform_get_irq(pdev, i);
+		if (ret < 0) {
+			dev_err(gpi_dev->dev, "platform_get_irq failed for %d:%d\n", i, ret);
+			return ret;
+		}
+		gpii->irq = ret;
+
+		/* set up channel specific register info */
+		for (chan = 0; chan < MAX_CHANNELS_PER_GPII; chan++) {
+			struct gchan *gchan = &gpii->gchan[chan];
+
+			/* set up ch cntxt register map */
+			gchan->ch_cntxt_base_reg = gpi_dev->ee_base +
+				GPII_n_CH_k_CNTXT_0_OFFS(i, chan);
+			gchan->ch_cntxt_db_reg = gpi_dev->ee_base +
+				GPII_n_CH_k_DOORBELL_0_OFFS(i, chan);
+			gchan->ch_cmd_reg = gpi_dev->ee_base + GPII_n_CH_CMD_OFFS(i);
+
+			/* vchan setup */
+			vchan_init(&gchan->vc, &gpi_dev->dma_device);
+			gchan->vc.desc_free = gpi_desc_free;
+			gchan->chid = chan;
+			gchan->gpii = gpii;
+			gchan->dir = GPII_CHAN_DIR[chan];
+		}
+		mutex_init(&gpii->ctrl_lock);
+		rwlock_init(&gpii->pm_lock);
+		tasklet_init(&gpii->ev_task, gpi_ev_tasklet,
+			     (unsigned long)gpii);
+		init_completion(&gpii->cmd_completion);
+		gpii->gpii_id = i;
+		gpii->regs = gpi_dev->ee_base;
+		gpii->gpi_dev = gpi_dev;
+	}
+
+	platform_set_drvdata(pdev, gpi_dev);
+
+	/* clear and Set capabilities */
+	dma_cap_zero(gpi_dev->dma_device.cap_mask);
+	dma_cap_set(DMA_SLAVE, gpi_dev->dma_device.cap_mask);
+
+	/* configure dmaengine apis */
+	gpi_dev->dma_device.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	gpi_dev->dma_device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+	gpi_dev->dma_device.src_addr_widths = DMA_SLAVE_BUSWIDTH_8_BYTES;
+	gpi_dev->dma_device.dst_addr_widths = DMA_SLAVE_BUSWIDTH_8_BYTES;
+	gpi_dev->dma_device.device_alloc_chan_resources = gpi_alloc_chan_resources;
+	gpi_dev->dma_device.device_free_chan_resources = gpi_free_chan_resources;
+	gpi_dev->dma_device.device_tx_status = dma_cookie_status;
+	gpi_dev->dma_device.device_issue_pending = gpi_issue_pending;
+	gpi_dev->dma_device.device_prep_slave_sg = gpi_prep_slave_sg;
+	gpi_dev->dma_device.device_config = gpi_peripheral_config;
+	gpi_dev->dma_device.device_terminate_all = gpi_terminate_all;
+	gpi_dev->dma_device.dev = gpi_dev->dev;
+	gpi_dev->dma_device.device_pause = gpi_pause;
+	gpi_dev->dma_device.device_resume = gpi_resume;
+
+	/* register with dmaengine framework */
+	ret = dma_async_device_register(&gpi_dev->dma_device);
+	if (ret) {
+		dev_err(gpi_dev->dev, "async_device_register failed ret:%d", ret);
+		return ret;
+	}
+
+	ret = of_dma_controller_register(gpi_dev->dev->of_node,
+					 gpi_of_dma_xlate, gpi_dev);
+	if (ret) {
+		dev_err(gpi_dev->dev, "of_dma_controller_reg failed ret:%d", ret);
+		return ret;
+	}
+
+	return ret;
+}
+
+static const struct of_device_id gpi_of_match[] = {
+	{ .compatible = "qcom,gpi-dma" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, gpi_of_match);
+
+static struct platform_driver gpi_driver = {
+	.probe = gpi_probe,
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = gpi_of_match,
+	},
+};
+
+static int __init gpi_init(void)
+{
+	return platform_driver_register(&gpi_driver);
+}
+subsys_initcall(gpi_init)
+
+MODULE_DESCRIPTION("QCOM GPI DMA engine driver");
+MODULE_LICENSE("GPL v2");
-- 
2.26.2


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-09-23  6:34 ` [PATCH v3 2/3] dmaengine: add peripheral configuration Vinod Koul
@ 2020-09-29  8:06   ` Peter Ujfalusi
  2020-09-30  5:47     ` Peter Ujfalusi
  2020-10-01 11:23     ` Vinod Koul
  0 siblings, 2 replies; 12+ messages in thread
From: Peter Ujfalusi @ 2020-09-29  8:06 UTC (permalink / raw)
  To: Vinod Koul, dmaengine
  Cc: Rob Herring, Bjorn Andersson, linux-arm-msm, devicetree, linux-kernel



On 23/09/2020 9.34, Vinod Koul wrote:
> Some complex dmaengine controllers have capability to program the
> peripheral device, so pass on the peripheral configuration as part of
> dma_slave_config
> 
> Signed-off-by: Vinod Koul <vkoul@kernel.org>
> ---
>  include/linux/dmaengine.h | 91 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 91 insertions(+)
> 
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 6fbd5c99e30c..bbc32271ad7f 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -380,6 +380,94 @@ enum dma_slave_buswidth {
>  	DMA_SLAVE_BUSWIDTH_64_BYTES = 64,
>  };
>  
> +/**
> + * enum spi_transfer_cmd - spi transfer commands
> + */
> +enum spi_transfer_cmd {
> +	SPI_TX = 1,
> +	SPI_RX,
> +	SPI_DUPLEX,
> +};
> +
> +/**
> + * struct dmaengine_spi_config - spi config for peripheral
> + *
> + * @loopback_en: spi loopback enable when set
> + * @clock_pol: clock polarity
> + * @data_pol: data polarity

*_pol_high ?

> + * @pack_en: process tx/rx buffers as packed

what does this mean?

> + * @word_len: spi word length
> + * @clk_div: source clock divider
> + * @clk_src: serial clock

we tend to use common clock framework for clock configuration?

> + * @cmd: spi cmd
> + * @cs: chip select toggle
> + */
> +struct dmaengine_spi_config {
> +	u8 loopback_en;
> +	u8 clock_pol;
> +	u8 data_pol;
> +	u8 pack_en;
> +	u8 word_len;
> +	u32 clk_div;
> +	u32 clk_src;
> +	u8 fragmentation;

This is not documented and I can not really guess what it is.

> +	enum spi_transfer_cmd cmd;
> +	u8 cs;
> +};
> +
> +enum i2c_op {
> +	I2C_WRITE = 1,
> +	I2C_READ,
> +};
> +
> +/**
> + * struct dmaengine_i2c_config - i2c config for peripheral
> + *
> + * @pack_enable: process tx/rx buffers as packed

Is this the same thing as with the spi?

> + * @cycle_count: clock cycles to be sent
> + * @high_count: high period of clock
> + * @low_count: low period of clock
> + * @clk_div: source clock divider
> + * @addr: i2c bus address
> + * @stretch: stretch the clock at eot
> + * @op: i2c cmd
> + */
> +struct dmaengine_i2c_config {
> +	u8 pack_enable;
> +	u8 cycle_count;
> +	u8 high_count;
> +	u8 low_count;
> +	u16 clk_div;
> +	u8 addr;
> +	u8 stretch;
> +	enum i2c_op op;
> +	bool multi_msg;

Not documented.
Is it indicates multiple-byte read/write or multiple messages?

> +};
> +
> +enum dmaengine_peripheral {
> +	DMAENGINE_PERIPHERAL_SPI = 1,
> +	DMAENGINE_PERIPHERAL_UART = 2,
> +	DMAENGINE_PERIPHERAL_I2C = 3,
> +	DMAENGINE_PERIPHERAL_LAST = DMAENGINE_PERIPHERAL_I2C,
> +};
> +
> +/**
> + * struct dmaengine_peripheral_config - peripheral configuration for
> + * dmaengine peripherals
> + *
> + * @peripheral: type of peripheral to DMA to/from
> + * @set_config: set peripheral config
> + * @rx_len: receive length for buffer

Why is it part of the peripheral config? You get the buffer via
prep_slave_sg(). Or is this something else?

The GPI driver uses the rx_len for DMA_MEM_TO_DEV (tx) setup.

> + * @spi: peripheral config for spi
> + * @i2c: peripheral config for i2c
> + */
> +struct dmaengine_peripheral_config {
> +	enum dmaengine_peripheral peripheral;
> +	u8 set_config;
> +	u32 rx_len;
> +	struct dmaengine_spi_config spi;
> +	struct dmaengine_i2c_config i2c;

I know that you want this to be as generic as much as it is possible,
but do we really want to?
GPIv2 will also handle I2S peripheral, other vendor's similar solution
would require different sets of parameters unique to their IPs?

How we are going to handle similar setups for DMA which is used for
networking, SPI/I2C/I2S/NAND/display/capture, etc?

Imho these settings are really part of the peripheral's domain and not
the DMA. It is just a small detail that instead of direct register
writes, your setup is using the DMA descriptors to write.
It is similar to what I use as metadata (part of the descriptor belongs
and owned by the client driver).

I think it would be better to have:

enum dmaengine_peripheral {
	DMAENGINE_PERIPHERAL_GPI_SPI = 1,
	DMAENGINE_PERIPHERAL_GPI_UART,
	DMAENGINE_PERIPHERAL_GPI_I2C,
	DMAENGINE_PERIPHERAL_XYZ_SPI,
	DMAENGINE_PERIPHERAL_XYZ_AASRC,
	DMAENGINE_PERIPHERAL_ABC_CAM,
	...
	DMAENGINE_PERIPHERAL_LAST,
};

enum dmaengine_peripheral peripheral_type;
void *peripheral_config;


and that's it. The set_config is specific to GPI.
It can be debated where the structs should be defined, in the generic
dmaengine.h or in include/linux/dma/ as controller specific
(gpi_peripheral.h) or a generic one, like dmaengine_peripheral.h

The SPI/I2C/UART client of yours would pass the GPI specific struct as
in any case it has to know what is the DMA it is serviced by.

> +};
>  /**
>   * struct dma_slave_config - dma slave channel runtime config
>   * @direction: whether the data shall go in or out on this slave
> @@ -418,6 +506,8 @@ enum dma_slave_buswidth {
>   * @slave_id: Slave requester id. Only valid for slave channels. The dma
>   * slave peripheral will have unique id as dma requester which need to be
>   * pass as slave config.
> + * @peripheral: peripheral configuration for programming peripheral for
> + * dmaengine transfer
>   *
>   * This struct is passed in as configuration data to a DMA engine
>   * in order to set up a certain channel for DMA transport at runtime.
> @@ -443,6 +533,7 @@ struct dma_slave_config {
>  	u32 dst_port_window_size;
>  	bool device_fc;
>  	unsigned int slave_id;
> +	struct dmaengine_peripheral_config *peripheral;
>  };
>  
>  /**
> 

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding
  2020-09-23  6:34 ` [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding Vinod Koul
@ 2020-09-29 18:44   ` Rob Herring
  2020-10-01 11:14     ` Vinod Koul
  0 siblings, 1 reply; 12+ messages in thread
From: Rob Herring @ 2020-09-29 18:44 UTC (permalink / raw)
  To: Vinod Koul
  Cc: dmaengine, Bjorn Andersson, linux-arm-msm, devicetree,
	linux-kernel, Peter Ujfalusi

On Wed, Sep 23, 2020 at 12:04:08PM +0530, Vinod Koul wrote:
> Add devicetree binding documentation for GPI DMA controller
> implemented on Qualcomm SoCs
> 
> Signed-off-by: Vinod Koul <vkoul@kernel.org>
> ---
>  .../devicetree/bindings/dma/qcom,gpi.yaml     | 86 +++++++++++++++++++
>  include/dt-bindings/dma/qcom-gpi.h            | 11 +++
>  2 files changed, 97 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/dma/qcom,gpi.yaml
>  create mode 100644 include/dt-bindings/dma/qcom-gpi.h
> 
> diff --git a/Documentation/devicetree/bindings/dma/qcom,gpi.yaml b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
> new file mode 100644
> index 000000000000..82f404bc8745
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/qcom,gpi.yaml
> @@ -0,0 +1,86 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/dma/qcom,gpi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Technologies Inc GPI DMA controller
> +
> +maintainers:
> +  - Vinod Koul <vkoul@kernel.org>
> +
> +description: |
> +  QCOM GPI DMA controller provides DMA capabilities for
> +  peripheral buses such as I2C, UART, and SPI.
> +
> +allOf:
> +  - $ref: "dma-controller.yaml#"
> +
> +properties:
> +  compatible:
> +    enum:
> +      - qcom,gpi-dma

Should be SoC specific.

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    description:
> +      Interrupt lines for each GPII instance

GPII or GPI?

> +    maxItems: 13
> +
> +  "#dma-cells":
> +    const: 3
> +    description: >
> +      DMA clients must use the format described in dma.txt, giving a phandle
> +      to the DMA controller plus the following 3 integer cells:
> +      - channel: if set to 0xffffffff, any available channel will be allocated
> +        for the client. Otherwise, the exact channel specified will be used.
> +      - seid: serial id of the client as defined in the SoC documentation.
> +      - client: type of the client as defined in dt-bindings/dma/qcom-gpi.h
> +
> +  iommus:
> +    maxItems: 1
> +
> +  dma-channels:
> +    maxItems: 1

Not an array. Is there a maximum number of channels or 2^32 is valid?

> +
> +  dma-channel-mask:
> +    maxItems: 1

So up to 32 channels?

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - "#dma-cells"
> +  - iommus
> +  - dma-channels
> +  - dma-channel-mask
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/dma/qcom-gpi.h>
> +    gpi_dma0: dma-controller@800000 {
> +        compatible = "qcom,gpi-dma";
> +        #dma-cells = <3>;
> +        reg = <0x00800000 0x60000>;
> +        iommus = <&apps_smmu 0x0016 0x0>;
> +        dma-channels = <13>;
> +        dma-channel-mask = <0xfa>;
> +        interrupts = <GIC_SPI 244 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 245 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 246 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 247 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 248 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 249 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 250 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 251 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 252 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 253 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 254 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 255 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 256 IRQ_TYPE_LEVEL_HIGH>;
> +    };
> +
> +...
> diff --git a/include/dt-bindings/dma/qcom-gpi.h b/include/dt-bindings/dma/qcom-gpi.h
> new file mode 100644
> index 000000000000..71f79eb7614c
> --- /dev/null
> +++ b/include/dt-bindings/dma/qcom-gpi.h
> @@ -0,0 +1,11 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (c) 2020, Linaro Ltd.  */
> +
> +#ifndef __DT_BINDINGS_DMA_QCOM_GPI_H__
> +#define __DT_BINDINGS_DMA_QCOM_GPI_H__
> +
> +#define QCOM_GPI_SPI		1
> +#define QCOM_GPI_UART		2
> +#define QCOM_GPI_I2C		3
> +
> +#endif /* __DT_BINDINGS_DMA_QCOM_GPI_H__ */
> -- 
> 2.26.2
> 

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-09-29  8:06   ` Peter Ujfalusi
@ 2020-09-30  5:47     ` Peter Ujfalusi
  2020-10-01 11:23     ` Vinod Koul
  1 sibling, 0 replies; 12+ messages in thread
From: Peter Ujfalusi @ 2020-09-30  5:47 UTC (permalink / raw)
  To: Vinod Koul, dmaengine
  Cc: Rob Herring, Bjorn Andersson, linux-arm-msm, devicetree, linux-kernel

Hi Vinod,

On 29/09/2020 11.06, Peter Ujfalusi wrote:
> 
> I know that you want this to be as generic as much as it is possible,
> but do we really want to?
> GPIv2 will also handle I2S peripheral, other vendor's similar solution
> would require different sets of parameters unique to their IPs?
> 
> How we are going to handle similar setups for DMA which is used for
> networking, SPI/I2C/I2S/NAND/display/capture, etc?
> 
> Imho these settings are really part of the peripheral's domain and not
> the DMA. It is just a small detail that instead of direct register
> writes, your setup is using the DMA descriptors to write.
> It is similar to what I use as metadata (part of the descriptor belongs
> and owned by the client driver).
> 
> I think it would be better to have:
> 
> enum dmaengine_peripheral {
> 	DMAENGINE_PERIPHERAL_GPI_SPI = 1,
> 	DMAENGINE_PERIPHERAL_GPI_UART,
> 	DMAENGINE_PERIPHERAL_GPI_I2C,
> 	DMAENGINE_PERIPHERAL_XYZ_SPI,
> 	DMAENGINE_PERIPHERAL_XYZ_AASRC,
> 	DMAENGINE_PERIPHERAL_ABC_CAM,
> 	...
> 	DMAENGINE_PERIPHERAL_LAST,
> };
> 
> enum dmaengine_peripheral peripheral_type;
> void *peripheral_config;

TI have an AASRC (Audio Asynchronous Sample Rate Converted) in j721e and
to configure the DMA side (AASRC_PDMA) we need special configuration
parameters passed from the AASRC driver to the DMA channel.
This peripheral config extension would be perfect for it, but the
parameters I would need is not generic in any ways.

The other thing which might need to be considered is to have src/dst
pair of this. When we do DMA_DEV_TO_DEV, it would help to figure out
which side we should apply which config (if you have the same type of
device on both ends with different config?).


> and that's it. The set_config is specific to GPI.
> It can be debated where the structs should be defined, in the generic
> dmaengine.h or in include/linux/dma/ as controller specific
> (gpi_peripheral.h) or a generic one, like dmaengine_peripheral.h
> 
> The SPI/I2C/UART client of yours would pass the GPI specific struct as
> in any case it has to know what is the DMA it is serviced by.
> 
>> +};
>>  /**
>>   * struct dma_slave_config - dma slave channel runtime config
>>   * @direction: whether the data shall go in or out on this slave
>> @@ -418,6 +506,8 @@ enum dma_slave_buswidth {
>>   * @slave_id: Slave requester id. Only valid for slave channels. The dma
>>   * slave peripheral will have unique id as dma requester which need to be
>>   * pass as slave config.
>> + * @peripheral: peripheral configuration for programming peripheral for
>> + * dmaengine transfer
>>   *
>>   * This struct is passed in as configuration data to a DMA engine
>>   * in order to set up a certain channel for DMA transport at runtime.
>> @@ -443,6 +533,7 @@ struct dma_slave_config {
>>  	u32 dst_port_window_size;
>>  	bool device_fc;
>>  	unsigned int slave_id;
>> +	struct dmaengine_peripheral_config *peripheral;
>>  };
>>  
>>  /**
>>
> 
> - Péter
> 
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
> 

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding
  2020-09-29 18:44   ` Rob Herring
@ 2020-10-01 11:14     ` Vinod Koul
  0 siblings, 0 replies; 12+ messages in thread
From: Vinod Koul @ 2020-10-01 11:14 UTC (permalink / raw)
  To: Rob Herring
  Cc: dmaengine, Bjorn Andersson, linux-arm-msm, devicetree,
	linux-kernel, Peter Ujfalusi

Hi Rob,

On 29-09-20, 13:44, Rob Herring wrote:

> > +description: |
> > +  QCOM GPI DMA controller provides DMA capabilities for
> > +  peripheral buses such as I2C, UART, and SPI.
> > +
> > +allOf:
> > +  - $ref: "dma-controller.yaml#"
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - qcom,gpi-dma
> 
> Should be SoC specific.

Okay, will add

> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    description:
> > +      Interrupt lines for each GPII instance
> 
> GPII or GPI?

Hw uses GPII as "GPI Instance" :) so will update this

> > +    maxItems: 13
> > +
> > +  "#dma-cells":
> > +    const: 3
> > +    description: >
> > +      DMA clients must use the format described in dma.txt, giving a phandle
> > +      to the DMA controller plus the following 3 integer cells:
> > +      - channel: if set to 0xffffffff, any available channel will be allocated
> > +        for the client. Otherwise, the exact channel specified will be used.
> > +      - seid: serial id of the client as defined in the SoC documentation.
> > +      - client: type of the client as defined in dt-bindings/dma/qcom-gpi.h
> > +
> > +  iommus:
> > +    maxItems: 1
> > +
> > +  dma-channels:
> > +    maxItems: 1
> 
> Not an array. Is there a maximum number of channels or 2^32 is valid?

I have not seen any max limit put, but we can be assured that it will
not go to 2^32, we can put a reasonable limit ..

Will add maximum :)

> > +
> > +  dma-channel-mask:
> > +    maxItems: 1
> 
> So up to 32 channels?

yep!

-- 
~Vinod

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-09-29  8:06   ` Peter Ujfalusi
  2020-09-30  5:47     ` Peter Ujfalusi
@ 2020-10-01 11:23     ` Vinod Koul
  2020-10-02  8:48       ` Peter Ujfalusi
  1 sibling, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2020-10-01 11:23 UTC (permalink / raw)
  To: Peter Ujfalusi
  Cc: dmaengine, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel

Hi Peter,

On 29-09-20, 11:06, Peter Ujfalusi wrote:

> > + * @spi: peripheral config for spi
> > + * @i2c: peripheral config for i2c
> > + */
> > +struct dmaengine_peripheral_config {
> > +	enum dmaengine_peripheral peripheral;
> > +	u8 set_config;
> > +	u32 rx_len;
> > +	struct dmaengine_spi_config spi;
> > +	struct dmaengine_i2c_config i2c;
> 
> I know that you want this to be as generic as much as it is possible,
> but do we really want to?

That is really a good question ;-)

> GPIv2 will also handle I2S peripheral, other vendor's similar solution

Not I2S, but yes but additional peripherals is always a question

> would require different sets of parameters unique to their IPs?
> 
> How we are going to handle similar setups for DMA which is used for
> networking, SPI/I2C/I2S/NAND/display/capture, etc?
> 
> Imho these settings are really part of the peripheral's domain and not
> the DMA. It is just a small detail that instead of direct register
> writes, your setup is using the DMA descriptors to write.
> It is similar to what I use as metadata (part of the descriptor belongs
> and owned by the client driver).
> 
> I think it would be better to have:
> 
> enum dmaengine_peripheral {
> 	DMAENGINE_PERIPHERAL_GPI_SPI = 1,
> 	DMAENGINE_PERIPHERAL_GPI_UART,
> 	DMAENGINE_PERIPHERAL_GPI_I2C,
> 	DMAENGINE_PERIPHERAL_XYZ_SPI,
> 	DMAENGINE_PERIPHERAL_XYZ_AASRC,
> 	DMAENGINE_PERIPHERAL_ABC_CAM,
> 	...
> 	DMAENGINE_PERIPHERAL_LAST,
> };
> 
> enum dmaengine_peripheral peripheral_type;
> void *peripheral_config;
> 
> 
> and that's it. The set_config is specific to GPI.
> It can be debated where the structs should be defined, in the generic
> dmaengine.h or in include/linux/dma/ as controller specific
> (gpi_peripheral.h) or a generic one, like dmaengine_peripheral.h
> 
> The SPI/I2C/UART client of yours would pass the GPI specific struct as
> in any case it has to know what is the DMA it is serviced by.

If we want to take that approach, I can actually move the whole logic of
creating the specific TREs from DMA to clients and they pass on TRE
values and driver adds to ring after appending DMA TREs

Question is how should this interface look like? reuse metadata or add a
new API which sets the txn specific data (void pointer and size) to the
txn.. 

-- 
~Vinod

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-10-01 11:23     ` Vinod Koul
@ 2020-10-02  8:48       ` Peter Ujfalusi
  2020-10-07 11:28         ` Vinod Koul
  0 siblings, 1 reply; 12+ messages in thread
From: Peter Ujfalusi @ 2020-10-02  8:48 UTC (permalink / raw)
  To: Vinod Koul
  Cc: dmaengine, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel

Hi Vinod,

On 01/10/2020 14.23, Vinod Koul wrote:
> Hi Peter,
> 
> On 29-09-20, 11:06, Peter Ujfalusi wrote:
> 
>>> + * @spi: peripheral config for spi
>>> + * @i2c: peripheral config for i2c
>>> + */
>>> +struct dmaengine_peripheral_config {
>>> +	enum dmaengine_peripheral peripheral;
>>> +	u8 set_config;
>>> +	u32 rx_len;
>>> +	struct dmaengine_spi_config spi;
>>> +	struct dmaengine_i2c_config i2c;
>>
>> I know that you want this to be as generic as much as it is possible,
>> but do we really want to?
> 
> That is really a good question ;-)
> 
>> GPIv2 will also handle I2S peripheral, other vendor's similar solution
> 
> Not I2S, but yes but additional peripherals is always a question

Never underestimate the 'creativity'.

>> would require different sets of parameters unique to their IPs?
>>
>> How we are going to handle similar setups for DMA which is used for
>> networking, SPI/I2C/I2S/NAND/display/capture, etc?
>>
>> Imho these settings are really part of the peripheral's domain and not
>> the DMA. It is just a small detail that instead of direct register
>> writes, your setup is using the DMA descriptors to write.
>> It is similar to what I use as metadata (part of the descriptor belongs
>> and owned by the client driver).
>>
>> I think it would be better to have:
>>
>> enum dmaengine_peripheral {
>> 	DMAENGINE_PERIPHERAL_GPI_SPI = 1,
>> 	DMAENGINE_PERIPHERAL_GPI_UART,
>> 	DMAENGINE_PERIPHERAL_GPI_I2C,
>> 	DMAENGINE_PERIPHERAL_XYZ_SPI,
>> 	DMAENGINE_PERIPHERAL_XYZ_AASRC,
>> 	DMAENGINE_PERIPHERAL_ABC_CAM,
>> 	...
>> 	DMAENGINE_PERIPHERAL_LAST,
>> };
>>
>> enum dmaengine_peripheral peripheral_type;
>> void *peripheral_config;
>>
>>
>> and that's it. The set_config is specific to GPI.
>> It can be debated where the structs should be defined, in the generic
>> dmaengine.h or in include/linux/dma/ as controller specific
>> (gpi_peripheral.h) or a generic one, like dmaengine_peripheral.h
>>
>> The SPI/I2C/UART client of yours would pass the GPI specific struct as
>> in any case it has to know what is the DMA it is serviced by.
> 
> If we want to take that approach, I can actually move the whole logic of
> creating the specific TREs from DMA to clients and they pass on TRE
> values and driver adds to ring after appending DMA TREs

The drawback is that you are tying the driver to a specific DMA with
directly giving the TREs. If the TRE (or other method) is used by a
newer device you need to work on both sides.

> Question is how should this interface look like? reuse metadata or add a
> new API which sets the txn specific data (void pointer and size) to the
> txn.. 

It depends which is best for the use case.
I see the metadata useful when you need to send different
metadata/configuration with each transfer.
It can be also useful when you need it seldom, but for your use case and
setup the dma_slave_config extended with

enum dmaengine_peripheral peripheral_type;
void *peripheral_config;

would be a bit more explicit.

I would then deal with the peripheral config in this way:
when the DMA driver's device_config is called, I would take the
parameters and set a flag that the config needs to be processed as it
has changed.
In the next prep_slave_sg() then I would prepare the TREs with the
config and clear the flag that the next transfer does not need the
configuration anymore.

In this way each dmaengine_slave_config() will trigger at the next
prep_slave_sg time configuration update for the peripheral to be
included in the TREs.
The set_config would be internal to the DMA driver, clients just need to
update the configuration when they need to and everything is taken care of.

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-10-02  8:48       ` Peter Ujfalusi
@ 2020-10-07 11:28         ` Vinod Koul
  2020-10-07 11:49           ` Peter Ujfalusi
  0 siblings, 1 reply; 12+ messages in thread
From: Vinod Koul @ 2020-10-07 11:28 UTC (permalink / raw)
  To: Peter Ujfalusi
  Cc: dmaengine, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel

Hi Peter,

On 02-10-20, 11:48, Peter Ujfalusi wrote:

> It depends which is best for the use case.
> I see the metadata useful when you need to send different
> metadata/configuration with each transfer.
> It can be also useful when you need it seldom, but for your use case and
> setup the dma_slave_config extended with
> 
> enum dmaengine_peripheral peripheral_type;
> void *peripheral_config;
> 
> would be a bit more explicit.
> 
> I would then deal with the peripheral config in this way:
> when the DMA driver's device_config is called, I would take the
> parameters and set a flag that the config needs to be processed as it
> has changed.
> In the next prep_slave_sg() then I would prepare the TREs with the
> config and clear the flag that the next transfer does not need the
> configuration anymore.
> 
> In this way each dmaengine_slave_config() will trigger at the next
> prep_slave_sg time configuration update for the peripheral to be
> included in the TREs.
> The set_config would be internal to the DMA driver, clients just need to
> update the configuration when they need to and everything is taken care of.

Ok I am going to drop the dmaengine_peripheral and make
peripheral_config as as you proposed.

So will add following to dma_slave_config:
        void *peripheral_config;

Driver can define the config they would like and use.

We can eventually look at common implementations and try to unify once
we have more users

-- 
~Vinod

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v3 2/3] dmaengine: add peripheral configuration
  2020-10-07 11:28         ` Vinod Koul
@ 2020-10-07 11:49           ` Peter Ujfalusi
  0 siblings, 0 replies; 12+ messages in thread
From: Peter Ujfalusi @ 2020-10-07 11:49 UTC (permalink / raw)
  To: Vinod Koul
  Cc: dmaengine, Rob Herring, Bjorn Andersson, linux-arm-msm,
	devicetree, linux-kernel

Hi Vinod,

On 07/10/2020 14.28, Vinod Koul wrote:
> Hi Peter,
> 
> On 02-10-20, 11:48, Peter Ujfalusi wrote:
> 
>> It depends which is best for the use case.
>> I see the metadata useful when you need to send different
>> metadata/configuration with each transfer.
>> It can be also useful when you need it seldom, but for your use case and
>> setup the dma_slave_config extended with
>>
>> enum dmaengine_peripheral peripheral_type;
>> void *peripheral_config;
>>
>> would be a bit more explicit.
>>
>> I would then deal with the peripheral config in this way:
>> when the DMA driver's device_config is called, I would take the
>> parameters and set a flag that the config needs to be processed as it
>> has changed.
>> In the next prep_slave_sg() then I would prepare the TREs with the
>> config and clear the flag that the next transfer does not need the
>> configuration anymore.
>>
>> In this way each dmaengine_slave_config() will trigger at the next
>> prep_slave_sg time configuration update for the peripheral to be
>> included in the TREs.
>> The set_config would be internal to the DMA driver, clients just need to
>> update the configuration when they need to and everything is taken care of.
> 
> Ok I am going to drop the dmaengine_peripheral and make
> peripheral_config as as you proposed.
> 
> So will add following to dma_slave_config:
>         void *peripheral_config;
> 
> Driver can define the config they would like and use.
> 
> We can eventually look at common implementations and try to unify once
> we have more users

Sound good to me!

- Péter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2020-10-07 11:49 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-09-23  6:34 [PATCH v3 0/3] dmaengine: Add support for QCOM GSI dma controller Vinod Koul
2020-09-23  6:34 ` [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding Vinod Koul
2020-09-29 18:44   ` Rob Herring
2020-10-01 11:14     ` Vinod Koul
2020-09-23  6:34 ` [PATCH v3 2/3] dmaengine: add peripheral configuration Vinod Koul
2020-09-29  8:06   ` Peter Ujfalusi
2020-09-30  5:47     ` Peter Ujfalusi
2020-10-01 11:23     ` Vinod Koul
2020-10-02  8:48       ` Peter Ujfalusi
2020-10-07 11:28         ` Vinod Koul
2020-10-07 11:49           ` Peter Ujfalusi
2020-09-23  6:34 ` [PATCH v3 3/3] dmaengine: qcom: Add GPI dma driver Vinod Koul

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