drm: msm: a6xx: Add support for A618

This patch adds support for enabling Graphics Bus Interface(GBIF)
used in multiple A6xx series chipets. Also makes changes to the
PDC/RSC sequencing specifically required for A618. This is needed
for proper interfacing with RPMH.

Signed-off-by: Sharat Masetty <smasetty@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

1 files changed, 65 insertions, 5 deletions

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 686c34d706b0..daf07800cde0 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-/* Copyright (c) 2017-2018 The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2017-2019 The Linux Foundation. All rights reserved. */
 
 
 #include "msm_gem.h"
@@ -378,6 +378,18 @@ static int a6xx_hw_init(struct msm_gpu *gpu)
 	struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
 	int ret;
 
+	/*
+	 * During a previous slumber, GBIF halt is asserted to ensure
+	 * no further transaction can go through GPU before GPU
+	 * headswitch is turned off.
+	 *
+	 * This halt is deasserted once headswitch goes off but
+	 * incase headswitch doesn't goes off clear GBIF halt
+	 * here to ensure GPU wake-up doesn't fail because of
+	 * halted GPU transactions.
+	 */
+	gpu_write(gpu, REG_A6XX_GBIF_HALT, 0x0);
+
 	/* Make sure the GMU keeps the GPU on while we set it up */
 	a6xx_gmu_set_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);
 
@@ -406,12 +418,17 @@ static int a6xx_hw_init(struct msm_gpu *gpu)
 	gpu_write(gpu, REG_A6XX_TPL1_ADDR_MODE_CNTL, 0x1);
 	gpu_write(gpu, REG_A6XX_RBBM_SECVID_TSB_ADDR_MODE_CNTL, 0x1);
 
-	/* enable hardware clockgating */
-	a6xx_set_hwcg(gpu, true);
+	/*
+	 * enable hardware clockgating
+	 * For now enable clock gating only for a630
+	 */
+	if (adreno_is_a630(adreno_gpu))
+		a6xx_set_hwcg(gpu, true);
 
-	/* VBIF start */
-	gpu_write(gpu, REG_A6XX_VBIF_GATE_OFF_WRREQ_EN, 0x00000009);
+	/* VBIF/GBIF start*/
 	gpu_write(gpu, REG_A6XX_RBBM_VBIF_CLIENT_QOS_CNTL, 0x3);
+	if (adreno_is_a630(adreno_gpu))
+		gpu_write(gpu, REG_A6XX_VBIF_GATE_OFF_WRREQ_EN, 0x00000009);
 
 	/* Make all blocks contribute to the GPU BUSY perf counter */
 	gpu_write(gpu, REG_A6XX_RBBM_PERFCTR_GPU_BUSY_MASKED, 0xffffffff);
@@ -731,6 +748,39 @@ static const u32 a6xx_register_offsets[REG_ADRENO_REGISTER_MAX] = {
 	REG_ADRENO_DEFINE(REG_ADRENO_CP_RB_CNTL, REG_A6XX_CP_RB_CNTL),
 };
 
+#define GBIF_CLIENT_HALT_MASK             BIT(0)
+#define GBIF_ARB_HALT_MASK                BIT(1)
+
+static void a6xx_bus_clear_pending_transactions(struct adreno_gpu *adreno_gpu)
+{
+	struct msm_gpu *gpu = &adreno_gpu->base;
+
+	if(!a6xx_has_gbif(adreno_gpu)){
+		gpu_write(gpu, REG_A6XX_VBIF_XIN_HALT_CTRL0, 0xf);
+		spin_until((gpu_read(gpu, REG_A6XX_VBIF_XIN_HALT_CTRL1) &
+								0xf) == 0xf);
+		gpu_write(gpu, REG_A6XX_VBIF_XIN_HALT_CTRL0, 0);
+
+		return;
+	}
+
+	/* Halt new client requests on GBIF */
+	gpu_write(gpu, REG_A6XX_GBIF_HALT, GBIF_CLIENT_HALT_MASK);
+	spin_until((gpu_read(gpu, REG_A6XX_GBIF_HALT_ACK) &
+			(GBIF_CLIENT_HALT_MASK)) == GBIF_CLIENT_HALT_MASK);
+
+	/* Halt all AXI requests on GBIF */
+	gpu_write(gpu, REG_A6XX_GBIF_HALT, GBIF_ARB_HALT_MASK);
+	spin_until((gpu_read(gpu,  REG_A6XX_GBIF_HALT_ACK) &
+			(GBIF_ARB_HALT_MASK)) == GBIF_ARB_HALT_MASK);
+
+	/*
+	 * GMU needs DDR access in slumber path. Deassert GBIF halt now
+	 * to allow for GMU to access system memory.
+	 */
+	gpu_write(gpu, REG_A6XX_GBIF_HALT, 0x0);
+}
+
 static int a6xx_pm_resume(struct msm_gpu *gpu)
 {
 	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
@@ -755,6 +805,16 @@ static int a6xx_pm_suspend(struct msm_gpu *gpu)
 
 	devfreq_suspend_device(gpu->devfreq.devfreq);
 
+	/*
+	 * Make sure the GMU is idle before continuing (because some transitions
+	 * may use VBIF
+	 */
+	a6xx_gmu_wait_for_idle(&a6xx_gpu->gmu);
+
+	/* Clear the VBIF pipe before shutting down */
+	/* FIXME: This accesses the GPU - do we need to make sure it is on? */
+	a6xx_bus_clear_pending_transactions(adreno_gpu);
+
 	return a6xx_gmu_stop(a6xx_gpu);
 }