drm/radeon: program auxch directly (v2)

The atombios tables have an unfortunate restriction on only
being able to write 12 bytes, MST really wants 16-bytes here,
and since the hw can do it, we should just write directly to it.

This uses a module option to allow for it now, and maybe
we should provide the old code as a fallback for a while.

v2: (agd5f)
- move registers to a proper register header
- only enable on DCE5+
- enable by default on DCE5+
- Switch pad to aux mode before using it
- reformat instance handling to better match the
  rest of the driver

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/Makefile b/drivers/gpu/drm/radeon/Makefile
index 4605633..fa635f0 100644
--- a/drivers/gpu/drm/radeon/Makefile
+++ b/drivers/gpu/drm/radeon/Makefile
@@ -81,7 +81,7 @@
 	rv770_smc.o cypress_dpm.o btc_dpm.o sumo_dpm.o sumo_smc.o trinity_dpm.o \
 	trinity_smc.o ni_dpm.o si_smc.o si_dpm.o kv_smc.o kv_dpm.o ci_smc.o \
 	ci_dpm.o dce6_afmt.o radeon_vm.o radeon_ucode.o radeon_ib.o \
-	radeon_sync.o radeon_audio.o
+	radeon_sync.o radeon_audio.o radeon_dp_auxch.o
 
 radeon-$(CONFIG_MMU_NOTIFIER) += radeon_mn.o
 
diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c
index 8d74de8..a014c7b 100644
--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -158,7 +158,7 @@
 #define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
 
 static ssize_t
-radeon_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
+radeon_dp_aux_transfer_atom(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 {
 	struct radeon_i2c_chan *chan =
 		container_of(aux, struct radeon_i2c_chan, aux);
@@ -226,11 +226,20 @@
 
 void radeon_dp_aux_init(struct radeon_connector *radeon_connector)
 {
+	struct drm_device *dev = radeon_connector->base.dev;
+	struct radeon_device *rdev = dev->dev_private;
 	int ret;
 
 	radeon_connector->ddc_bus->rec.hpd = radeon_connector->hpd.hpd;
 	radeon_connector->ddc_bus->aux.dev = radeon_connector->base.kdev;
-	radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer;
+	if (ASIC_IS_DCE5(rdev)) {
+		if (radeon_auxch)
+			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_native;
+		else
+			radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
+	} else {
+		radeon_connector->ddc_bus->aux.transfer = radeon_dp_aux_transfer_atom;
+	}
 
 	ret = drm_dp_aux_register(&radeon_connector->ddc_bus->aux);
 	if (!ret)
diff --git a/drivers/gpu/drm/radeon/nid.h b/drivers/gpu/drm/radeon/nid.h
index 2e5cdc4..3b29083 100644
--- a/drivers/gpu/drm/radeon/nid.h
+++ b/drivers/gpu/drm/radeon/nid.h
@@ -816,6 +816,52 @@
 #define MC_PMG_CMD_MRS2                                 0x2b5c
 #define MC_SEQ_PMG_CMD_MRS2_LP                          0x2b60
 
+#define AUX_CONTROL					0x6200
+#define 	AUX_EN					(1 << 0)
+#define 	AUX_LS_READ_EN				(1 << 8)
+#define 	AUX_LS_UPDATE_DISABLE(x)		(((x) & 0x1) << 12)
+#define 	AUX_HPD_DISCON(x)			(((x) & 0x1) << 16)
+#define 	AUX_DET_EN				(1 << 18)
+#define 	AUX_HPD_SEL(x)				(((x) & 0x7) << 20)
+#define 	AUX_IMPCAL_REQ_EN			(1 << 24)
+#define 	AUX_TEST_MODE				(1 << 28)
+#define 	AUX_DEGLITCH_EN				(1 << 29)
+#define AUX_SW_CONTROL					0x6204
+#define 	AUX_SW_GO				(1 << 0)
+#define 	AUX_LS_READ_TRIG			(1 << 2)
+#define 	AUX_SW_START_DELAY(x)			(((x) & 0xf) << 4)
+#define 	AUX_SW_WR_BYTES(x)			(((x) & 0x1f) << 16)
+
+#define AUX_SW_INTERRUPT_CONTROL			0x620c
+#define 	AUX_SW_DONE_INT				(1 << 0)
+#define 	AUX_SW_DONE_ACK				(1 << 1)
+#define 	AUX_SW_DONE_MASK			(1 << 2)
+#define 	AUX_SW_LS_DONE_INT			(1 << 4)
+#define 	AUX_SW_LS_DONE_MASK			(1 << 6)
+#define AUX_SW_STATUS					0x6210
+#define 	AUX_SW_DONE				(1 << 0)
+#define 	AUX_SW_REQ				(1 << 1)
+#define 	AUX_SW_RX_TIMEOUT_STATE(x)		(((x) & 0x7) << 4)
+#define 	AUX_SW_RX_TIMEOUT			(1 << 7)
+#define 	AUX_SW_RX_OVERFLOW			(1 << 8)
+#define 	AUX_SW_RX_HPD_DISCON			(1 << 9)
+#define 	AUX_SW_RX_PARTIAL_BYTE			(1 << 10)
+#define 	AUX_SW_NON_AUX_MODE			(1 << 11)
+#define 	AUX_SW_RX_MIN_COUNT_VIOL		(1 << 12)
+#define 	AUX_SW_RX_INVALID_STOP			(1 << 14)
+#define 	AUX_SW_RX_SYNC_INVALID_L		(1 << 17)
+#define 	AUX_SW_RX_SYNC_INVALID_H		(1 << 18)
+#define 	AUX_SW_RX_INVALID_START			(1 << 19)
+#define 	AUX_SW_RX_RECV_NO_DET			(1 << 20)
+#define 	AUX_SW_RX_RECV_INVALID_H		(1 << 22)
+#define 	AUX_SW_RX_RECV_INVALID_V		(1 << 23)
+
+#define AUX_SW_DATA					0x6218
+#define AUX_SW_DATA_RW					(1 << 0)
+#define AUX_SW_DATA_MASK(x)				(((x) & 0xff) << 8)
+#define AUX_SW_DATA_INDEX(x)				(((x) & 0x1f) << 16)
+#define AUX_SW_AUTOINCREMENT_DISABLE			(1 << 31)
+
 #define	LB_SYNC_RESET_SEL				0x6b28
 #define		LB_SYNC_RESET_SEL_MASK			(3 << 0)
 #define		LB_SYNC_RESET_SEL_SHIFT			0
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 88bcada..26a339b 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -111,6 +111,7 @@
 extern int radeon_use_pflipirq;
 extern int radeon_bapm;
 extern int radeon_backlight;
+extern int radeon_auxch;
 
 /*
  * Copy from radeon_drv.h so we don't have to include both and have conflicting
diff --git a/drivers/gpu/drm/radeon/radeon_dp_auxch.c b/drivers/gpu/drm/radeon/radeon_dp_auxch.c
new file mode 100644
index 0000000..bf1fecc
--- /dev/null
+++ b/drivers/gpu/drm/radeon/radeon_dp_auxch.c
@@ -0,0 +1,206 @@
+/*
+ * Copyright 2015 Red Hat 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: Dave Airlie
+ */
+#include <drm/drmP.h>
+#include <drm/radeon_drm.h>
+#include "radeon.h"
+#include "nid.h"
+
+#define AUX_RX_ERROR_FLAGS (AUX_SW_RX_OVERFLOW |	     \
+			    AUX_SW_RX_HPD_DISCON |	     \
+			    AUX_SW_RX_PARTIAL_BYTE |	     \
+			    AUX_SW_NON_AUX_MODE |	     \
+			    AUX_SW_RX_MIN_COUNT_VIOL |	     \
+			    AUX_SW_RX_INVALID_STOP |	     \
+			    AUX_SW_RX_SYNC_INVALID_L |	     \
+			    AUX_SW_RX_SYNC_INVALID_H |	     \
+			    AUX_SW_RX_INVALID_START |	     \
+			    AUX_SW_RX_RECV_NO_DET |	     \
+			    AUX_SW_RX_RECV_INVALID_H |	     \
+			    AUX_SW_RX_RECV_INVALID_V)
+
+#define AUX_SW_REPLY_GET_BYTE_COUNT(x) (((x) >> 24) & 0x1f)
+
+#define BARE_ADDRESS_SIZE 3
+
+static const u32 aux_offset[] =
+{
+	0x6200 - 0x6200,
+	0x6250 - 0x6200,
+	0x62a0 - 0x6200,
+	0x6300 - 0x6200,
+	0x6350 - 0x6200,
+	0x63a0 - 0x6200,
+};
+
+ssize_t
+radeon_dp_aux_transfer_native(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
+{
+	struct radeon_i2c_chan *chan =
+		container_of(aux, struct radeon_i2c_chan, aux);
+	struct drm_device *dev = chan->dev;
+	struct radeon_device *rdev = dev->dev_private;
+	int ret = 0, i;
+	uint32_t tmp, ack = 0;
+	int instance = chan->rec.i2c_id & 0xf;
+	u8 byte;
+	u8 *buf = msg->buffer;
+	int retry_count = 0;
+	int bytes;
+	int msize;
+	bool is_write = false;
+
+	if (WARN_ON(msg->size > 16))
+		return -E2BIG;
+
+	switch (msg->request & ~DP_AUX_I2C_MOT) {
+	case DP_AUX_NATIVE_WRITE:
+	case DP_AUX_I2C_WRITE:
+		is_write = true;
+		break;
+	case DP_AUX_NATIVE_READ:
+	case DP_AUX_I2C_READ:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* work out two sizes required */
+	msize = 0;
+	bytes = BARE_ADDRESS_SIZE;
+	if (msg->size) {
+		msize = msg->size - 1;
+		bytes++;
+		if (is_write)
+			bytes += msg->size;
+	}
+
+	mutex_lock(&chan->mutex);
+
+	/* switch the pad to aux mode */
+	tmp = RREG32(chan->rec.mask_clk_reg);
+	tmp |= (1 << 16);
+	WREG32(chan->rec.mask_clk_reg, tmp);
+
+	/* setup AUX control register with correct HPD pin */
+	tmp = RREG32(AUX_CONTROL + aux_offset[instance]);
+
+	tmp &= AUX_HPD_SEL(0x7);
+	tmp |= AUX_HPD_SEL(chan->rec.hpd);
+	tmp |= AUX_EN | AUX_LS_READ_EN;
+
+	WREG32(AUX_CONTROL + aux_offset[instance], tmp);
+
+	/* atombios appears to write this twice lets copy it */
+	WREG32(AUX_SW_CONTROL + aux_offset[instance],
+	       AUX_SW_WR_BYTES(bytes));
+	WREG32(AUX_SW_CONTROL + aux_offset[instance],
+	       AUX_SW_WR_BYTES(bytes));
+
+	/* write the data header into the registers */
+	/* request, addres, msg size */
+	byte = (msg->request << 4);
+	WREG32(AUX_SW_DATA + aux_offset[instance],
+	       AUX_SW_DATA_MASK(byte) | AUX_SW_AUTOINCREMENT_DISABLE);
+
+	byte = (msg->address >> 8) & 0xff;
+	WREG32(AUX_SW_DATA + aux_offset[instance],
+	       AUX_SW_DATA_MASK(byte));
+
+	byte = msg->address & 0xff;
+	WREG32(AUX_SW_DATA + aux_offset[instance],
+	       AUX_SW_DATA_MASK(byte));
+
+	byte = msize;
+	WREG32(AUX_SW_DATA + aux_offset[instance],
+	       AUX_SW_DATA_MASK(byte));
+
+	/* if we are writing - write the msg buffer */
+	if (is_write) {
+		for (i = 0; i < msg->size; i++) {
+			WREG32(AUX_SW_DATA + aux_offset[instance],
+			       AUX_SW_DATA_MASK(buf[i]));
+		}
+	}
+
+	/* clear the ACK */
+	WREG32(AUX_SW_INTERRUPT_CONTROL + aux_offset[instance], AUX_SW_DONE_ACK);
+
+	/* write the size and GO bits */
+	WREG32(AUX_SW_CONTROL + aux_offset[instance],
+	       AUX_SW_WR_BYTES(bytes) | AUX_SW_GO);
+
+	/* poll the status registers - TODO irq support */
+	do {
+		tmp = RREG32(AUX_SW_STATUS + aux_offset[instance]);
+		if (tmp & AUX_SW_DONE) {
+			break;
+		}
+		usleep_range(100, 200);
+	} while (retry_count++ < 1000);
+
+	if (retry_count >= 1000) {
+		DRM_ERROR("auxch hw never signalled completion, error %08x\n", tmp);
+		ret = -EIO;
+		goto done;
+	}
+
+	if (tmp & AUX_SW_RX_TIMEOUT) {
+		DRM_DEBUG_KMS("dp_aux_ch timed out\n");
+		ret = -ETIMEDOUT;
+		goto done;
+	}
+	if (tmp & AUX_RX_ERROR_FLAGS) {
+		DRM_DEBUG_KMS("dp_aux_ch flags not zero: %08x\n", tmp);
+		ret = -EIO;
+		goto done;
+	}
+
+	bytes = AUX_SW_REPLY_GET_BYTE_COUNT(tmp);
+	if (bytes) {
+		WREG32(AUX_SW_DATA + aux_offset[instance],
+		       AUX_SW_DATA_RW | AUX_SW_AUTOINCREMENT_DISABLE);
+
+		tmp = RREG32(AUX_SW_DATA + aux_offset[instance]);
+		ack = (tmp >> 8) & 0xff;
+
+		for (i = 0; i < bytes - 1; i++) {
+			tmp = RREG32(AUX_SW_DATA + aux_offset[instance]);
+			if (buf)
+				buf[i] = (tmp >> 8) & 0xff;
+		}
+		if (buf)
+			ret = bytes - 1;
+	}
+
+	WREG32(AUX_SW_INTERRUPT_CONTROL + aux_offset[instance], AUX_SW_DONE_ACK);
+
+	if (is_write)
+		ret = msg->size;
+done:
+	mutex_unlock(&chan->mutex);
+
+	if (ret >= 0)
+		msg->reply = ack >> 4;
+	return ret;
+}
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 3b00690..b088507 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -190,6 +190,7 @@
 int radeon_use_pflipirq = 2;
 int radeon_bapm = -1;
 int radeon_backlight = -1;
+int radeon_auxch = -1;
 
 MODULE_PARM_DESC(no_wb, "Disable AGP writeback for scratch registers");
 module_param_named(no_wb, radeon_no_wb, int, 0444);
@@ -275,6 +276,9 @@
 MODULE_PARM_DESC(backlight, "backlight support (1 = enable, 0 = disable, -1 = auto)");
 module_param_named(backlight, radeon_backlight, int, 0444);
 
+MODULE_PARM_DESC(auxch, "Use native auxch experimental support (1 = enable, 0 = disable, -1 = auto)");
+module_param_named(auxch, radeon_auxch, int, 0444);
+
 static struct pci_device_id pciidlist[] = {
 	radeon_PCI_IDS
 };
diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index 664825c..60043bf 100644
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -722,6 +722,9 @@
 extern void radeon_dp_set_rx_power_state(struct drm_connector *connector,
 					 u8 power_state);
 extern void radeon_dp_aux_init(struct radeon_connector *radeon_connector);
+extern ssize_t
+radeon_dp_aux_transfer_native(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg);
+
 extern void atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mode);
 extern void radeon_atom_encoder_init(struct radeon_device *rdev);
 extern void radeon_atom_disp_eng_pll_init(struct radeon_device *rdev);