1 files changed, 541 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_sw.c b/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_sw.c
new file mode 100644
index 000000000000..f0266694cb56
--- /dev/null
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_i2c_sw.c
@@ -0,0 +1,541 @@
+/*
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+#include "dce_i2c.h"
+#include "dce_i2c_sw.h"
+#include "include/gpio_service_interface.h"
+#define SCL false
+#define SDA true
+
+void dce_i2c_sw_construct(
+	struct dce_i2c_sw *dce_i2c_sw,
+	struct dc_context *ctx)
+{
+	dce_i2c_sw->ctx = ctx;
+}
+
+static inline bool read_bit_from_ddc(
+	struct ddc *ddc,
+	bool data_nor_clock)
+{
+	uint32_t value = 0;
+
+	if (data_nor_clock)
+		dal_gpio_get_value(ddc->pin_data, &value);
+	else
+		dal_gpio_get_value(ddc->pin_clock, &value);
+
+	return (value != 0);
+}
+
+static inline void write_bit_to_ddc(
+	struct ddc *ddc,
+	bool data_nor_clock,
+	bool bit)
+{
+	uint32_t value = bit ? 1 : 0;
+
+	if (data_nor_clock)
+		dal_gpio_set_value(ddc->pin_data, value);
+	else
+		dal_gpio_set_value(ddc->pin_clock, value);
+}
+
+static void release_engine_dce_sw(
+	struct resource_pool *pool,
+	struct dce_i2c_sw *dce_i2c_sw)
+{
+	dal_ddc_close(dce_i2c_sw->ddc);
+	dce_i2c_sw->ddc = NULL;
+}
+
+static bool get_hw_supported_ddc_line(
+	struct ddc *ddc,
+	enum gpio_ddc_line *line)
+{
+	enum gpio_ddc_line line_found;
+
+	*line = GPIO_DDC_LINE_UNKNOWN;
+
+	if (!ddc) {
+		BREAK_TO_DEBUGGER();
+		return false;
+	}
+
+	if (!ddc->hw_info.hw_supported)
+		return false;
+
+	line_found = dal_ddc_get_line(ddc);
+
+	if (line_found >= GPIO_DDC_LINE_COUNT)
+		return false;
+
+	*line = line_found;
+
+	return true;
+}
+static bool wait_for_scl_high_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc,
+	uint16_t clock_delay_div_4)
+{
+	uint32_t scl_retry = 0;
+	uint32_t scl_retry_max = I2C_SW_TIMEOUT_DELAY / clock_delay_div_4;
+
+	udelay(clock_delay_div_4);
+
+	do {
+		if (read_bit_from_ddc(ddc, SCL))
+			return true;
+
+		udelay(clock_delay_div_4);
+
+		++scl_retry;
+	} while (scl_retry <= scl_retry_max);
+
+	return false;
+}
+static bool write_byte_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4,
+	uint8_t byte)
+{
+	int32_t shift = 7;
+	bool ack;
+
+	/* bits are transmitted serially, starting from MSB */
+
+	do {
+		udelay(clock_delay_div_4);
+
+		write_bit_to_ddc(ddc_handle, SDA, (byte >> shift) & 1);
+
+		udelay(clock_delay_div_4);
+
+		write_bit_to_ddc(ddc_handle, SCL, true);
+
+		if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+			return false;
+
+		write_bit_to_ddc(ddc_handle, SCL, false);
+
+		--shift;
+	} while (shift >= 0);
+
+	/* The display sends ACK by preventing the SDA from going high
+	 * after the SCL pulse we use to send our last data bit.
+	 * If the SDA goes high after that bit, it's a NACK
+	 */
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SDA, true);
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SCL, true);
+
+	if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+		return false;
+
+	/* read ACK bit */
+
+	ack = !read_bit_from_ddc(ddc_handle, SDA);
+
+	udelay(clock_delay_div_4 << 1);
+
+	write_bit_to_ddc(ddc_handle, SCL, false);
+
+	udelay(clock_delay_div_4 << 1);
+
+	return ack;
+}
+
+static bool read_byte_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4,
+	uint8_t *byte,
+	bool more)
+{
+	int32_t shift = 7;
+
+	uint8_t data = 0;
+
+	/* The data bits are read from MSB to LSB;
+	 * bit is read while SCL is high
+	 */
+
+	do {
+		write_bit_to_ddc(ddc_handle, SCL, true);
+
+		if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+			return false;
+
+		if (read_bit_from_ddc(ddc_handle, SDA))
+			data |= (1 << shift);
+
+		write_bit_to_ddc(ddc_handle, SCL, false);
+
+		udelay(clock_delay_div_4 << 1);
+
+		--shift;
+	} while (shift >= 0);
+
+	/* read only whole byte */
+
+	*byte = data;
+
+	udelay(clock_delay_div_4);
+
+	/* send the acknowledge bit:
+	 * SDA low means ACK, SDA high means NACK
+	 */
+
+	write_bit_to_ddc(ddc_handle, SDA, !more);
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SCL, true);
+
+	if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+		return false;
+
+	write_bit_to_ddc(ddc_handle, SCL, false);
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SDA, true);
+
+	udelay(clock_delay_div_4);
+
+	return true;
+}
+static bool stop_sync_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4)
+{
+	uint32_t retry = 0;
+
+	/* The I2C communications stop signal is:
+	 * the SDA going high from low, while the SCL is high.
+	 */
+
+	write_bit_to_ddc(ddc_handle, SCL, false);
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SDA, false);
+
+	udelay(clock_delay_div_4);
+
+	write_bit_to_ddc(ddc_handle, SCL, true);
+
+	if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+		return false;
+
+	write_bit_to_ddc(ddc_handle, SDA, true);
+
+	do {
+		udelay(clock_delay_div_4);
+
+		if (read_bit_from_ddc(ddc_handle, SDA))
+			return true;
+
+		++retry;
+	} while (retry <= 2);
+
+	return false;
+}
+static bool i2c_write_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4,
+	uint8_t address,
+	uint32_t length,
+	const uint8_t *data)
+{
+	uint32_t i = 0;
+
+	if (!write_byte_sw(ctx, ddc_handle, clock_delay_div_4, address))
+		return false;
+
+	while (i < length) {
+		if (!write_byte_sw(ctx, ddc_handle, clock_delay_div_4, data[i]))
+			return false;
+		++i;
+	}
+
+	return true;
+}
+
+static bool i2c_read_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4,
+	uint8_t address,
+	uint32_t length,
+	uint8_t *data)
+{
+	uint32_t i = 0;
+
+	if (!write_byte_sw(ctx, ddc_handle, clock_delay_div_4, address))
+		return false;
+
+	while (i < length) {
+		if (!read_byte_sw(ctx, ddc_handle, clock_delay_div_4, data + i,
+			i < length - 1))
+			return false;
+		++i;
+	}
+
+	return true;
+}
+
+
+
+static bool start_sync_sw(
+	struct dc_context *ctx,
+	struct ddc *ddc_handle,
+	uint16_t clock_delay_div_4)
+{
+	uint32_t retry = 0;
+
+	/* The I2C communications start signal is:
+	 * the SDA going low from high, while the SCL is high.
+	 */
+
+	write_bit_to_ddc(ddc_handle, SCL, true);
+
+	udelay(clock_delay_div_4);
+
+	do {
+		write_bit_to_ddc(ddc_handle, SDA, true);
+
+		if (!read_bit_from_ddc(ddc_handle, SDA)) {
+			++retry;
+			continue;
+		}
+
+		udelay(clock_delay_div_4);
+
+		write_bit_to_ddc(ddc_handle, SCL, true);
+
+		if (!wait_for_scl_high_sw(ctx, ddc_handle, clock_delay_div_4))
+			break;
+
+		write_bit_to_ddc(ddc_handle, SDA, false);
+
+		udelay(clock_delay_div_4);
+
+		write_bit_to_ddc(ddc_handle, SCL, false);
+
+		udelay(clock_delay_div_4);
+
+		return true;
+	} while (retry <= I2C_SW_RETRIES);
+
+	return false;
+}
+
+void dce_i2c_sw_engine_set_speed(
+	struct dce_i2c_sw *engine,
+	uint32_t speed)
+{
+	ASSERT(speed);
+
+	engine->speed = speed ? speed : DCE_I2C_DEFAULT_I2C_SW_SPEED;
+
+	engine->clock_delay = 1000 / engine->speed;
+
+	if (engine->clock_delay < 12)
+		engine->clock_delay = 12;
+}
+
+bool dce_i2c_sw_engine_acquire_engine(
+	struct dce_i2c_sw *engine,
+	struct ddc *ddc)
+{
+	enum gpio_result result;
+
+	result = dal_ddc_open(ddc, GPIO_MODE_FAST_OUTPUT,
+		GPIO_DDC_CONFIG_TYPE_MODE_I2C);
+
+	if (result != GPIO_RESULT_OK)
+		return false;
+
+	engine->ddc = ddc;
+
+	return true;
+}
+bool dce_i2c_engine_acquire_sw(
+	struct dce_i2c_sw *dce_i2c_sw,
+	struct ddc *ddc_handle)
+{
+	uint32_t counter = 0;
+	bool result;
+
+	do {
+
+		result = dce_i2c_sw_engine_acquire_engine(
+				dce_i2c_sw, ddc_handle);
+
+		if (result)
+			break;
+
+		/* i2c_engine is busy by VBios, lets wait and retry */
+
+		udelay(10);
+
+		++counter;
+	} while (counter < 2);
+
+	return result;
+}
+
+
+
+
+void dce_i2c_sw_engine_submit_channel_request(
+	struct dce_i2c_sw *engine,
+	struct i2c_request_transaction_data *req)
+{
+	struct ddc *ddc = engine->ddc;
+	uint16_t clock_delay_div_4 = engine->clock_delay >> 2;
+
+	/* send sync (start / repeated start) */
+
+	bool result = start_sync_sw(engine->ctx, ddc, clock_delay_div_4);
+
+	/* process payload */
+
+	if (result) {
+		switch (req->action) {
+		case DCE_I2C_TRANSACTION_ACTION_I2C_WRITE:
+		case DCE_I2C_TRANSACTION_ACTION_I2C_WRITE_MOT:
+			result = i2c_write_sw(engine->ctx, ddc, clock_delay_div_4,
+				req->address, req->length, req->data);
+		break;
+		case DCE_I2C_TRANSACTION_ACTION_I2C_READ:
+		case DCE_I2C_TRANSACTION_ACTION_I2C_READ_MOT:
+			result = i2c_read_sw(engine->ctx, ddc, clock_delay_div_4,
+				req->address, req->length, req->data);
+		break;
+		default:
+			result = false;
+		break;
+		}
+	}
+
+	/* send stop if not 'mot' or operation failed */
+
+	if (!result ||
+		(req->action == DCE_I2C_TRANSACTION_ACTION_I2C_WRITE) ||
+		(req->action == DCE_I2C_TRANSACTION_ACTION_I2C_READ))
+		if (!stop_sync_sw(engine->ctx, ddc, clock_delay_div_4))
+			result = false;
+
+	req->status = result ?
+		I2C_CHANNEL_OPERATION_SUCCEEDED :
+		I2C_CHANNEL_OPERATION_FAILED;
+}
+bool dce_i2c_sw_engine_submit_payload(
+	struct dce_i2c_sw *engine,
+	struct i2c_payload *payload,
+	bool middle_of_transaction)
+{
+	struct i2c_request_transaction_data request;
+
+	if (!payload->write)
+		request.action = middle_of_transaction ?
+			DCE_I2C_TRANSACTION_ACTION_I2C_READ_MOT :
+			DCE_I2C_TRANSACTION_ACTION_I2C_READ;
+	else
+		request.action = middle_of_transaction ?
+			DCE_I2C_TRANSACTION_ACTION_I2C_WRITE_MOT :
+			DCE_I2C_TRANSACTION_ACTION_I2C_WRITE;
+
+	request.address = (uint8_t) ((payload->address << 1) | !payload->write);
+	request.length = payload->length;
+	request.data = payload->data;
+
+	dce_i2c_sw_engine_submit_channel_request(engine, &request);
+
+	if ((request.status == I2C_CHANNEL_OPERATION_ENGINE_BUSY) ||
+		(request.status == I2C_CHANNEL_OPERATION_FAILED))
+		return false;
+
+	return true;
+}
+bool dce_i2c_submit_command_sw(
+	struct resource_pool *pool,
+	struct ddc *ddc,
+	struct i2c_command *cmd,
+	struct dce_i2c_sw *dce_i2c_sw)
+{
+	uint8_t index_of_payload = 0;
+	bool result;
+
+	dce_i2c_sw_engine_set_speed(dce_i2c_sw, cmd->speed);
+
+	result = true;
+
+	while (index_of_payload < cmd->number_of_payloads) {
+		bool mot = (index_of_payload != cmd->number_of_payloads - 1);
+
+		struct i2c_payload *payload = cmd->payloads + index_of_payload;
+
+		if (!dce_i2c_sw_engine_submit_payload(
+			dce_i2c_sw, payload, mot)) {
+			result = false;
+			break;
+		}
+
+		++index_of_payload;
+	}
+
+	release_engine_dce_sw(pool, dce_i2c_sw);
+
+	return result;
+}
+struct dce_i2c_sw *dce_i2c_acquire_i2c_sw_engine(
+	struct resource_pool *pool,
+	struct ddc *ddc)
+{
+	enum gpio_ddc_line line;
+	struct dce_i2c_sw *engine = NULL;
+
+	if (get_hw_supported_ddc_line(ddc, &line))
+		engine = pool->sw_i2cs[line];
+
+	if (!engine)
+		return NULL;
+
+	if (!dce_i2c_engine_acquire_sw(engine, ddc))
+		return NULL;
+
+	return engine;
+}