From e9c00c0da9c85acdc776c5ee1f09dfad388eac09 Mon Sep 17 00:00:00 2001
From: Nicolas Benech <nbenech@nvidia.com>
Date: Thu, 17 Jan 2019 18:07:35 -0500
Subject: [PATCH] gpu: nvgpu: add error codes to mm_l2_flush

gv11b_mm_l2_flush was not checking error codes from the various
functions it was calling. MISRA Rule-17.7 requires the return value
of all functions to be used. This patch now checks return values and
propagates the error upstream.

JIRA NVGPU-677

Change-Id: I9005c6d3a406f9665d318014d21a1da34f87ca30
Signed-off-by: Nicolas Benech <nbenech@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1998809
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
---
 drivers/gpu/nvgpu/common/gr/global_ctx.c      |  4 +-
 drivers/gpu/nvgpu/common/ltc/ltc_gp10b.c      |  4 +-
 drivers/gpu/nvgpu/common/mm/gmmu/page_table.c |  8 +++-
 drivers/gpu/nvgpu/common/mm/mm.c              | 10 ++++-
 drivers/gpu/nvgpu/gk20a/gr_gk20a.c            | 37 ++++++++++++++-----
 drivers/gpu/nvgpu/gk20a/mm_gk20a.c            |  6 ++-
 drivers/gpu/nvgpu/gk20a/mm_gk20a.h            |  2 +-
 drivers/gpu/nvgpu/gv11b/mm_gv11b.c            | 36 ++++++++++++++----
 drivers/gpu/nvgpu/gv11b/mm_gv11b.h            |  2 +-
 drivers/gpu/nvgpu/gv11b/subctx_gv11b.c        |  9 ++++-
 drivers/gpu/nvgpu/include/nvgpu/gk20a.h       |  2 +-
 drivers/gpu/nvgpu/os/linux/ioctl_ctrl.c       | 12 ++++--
 drivers/gpu/nvgpu/vgpu/mm_vgpu.c              | 12 +++---
 drivers/gpu/nvgpu/vgpu/mm_vgpu.h              |  2 +-
 14 files changed, 107 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/nvgpu/common/gr/global_ctx.c b/drivers/gpu/nvgpu/common/gr/global_ctx.c
index 1e88891e7..db674bf93 100644
--- a/drivers/gpu/nvgpu/common/gr/global_ctx.c
+++ b/drivers/gpu/nvgpu/common/gr/global_ctx.c
@@ -278,7 +278,9 @@ void nvgpu_gr_global_ctx_load_local_golden_image(struct gk20a *g,
 {
 	/* Channel gr_ctx buffer is gpu cacheable.
 	   Flush and invalidate before cpu update. */
-	g->ops.mm.l2_flush(g, true);
+	if (g->ops.mm.l2_flush(g, true) != 0) {
+		nvgpu_err(g, "l2_flush failed");
+	}
 
 	nvgpu_mem_wr_n(g, target_mem, 0, local_golden_image->context,
 					 local_golden_image->size);
diff --git a/drivers/gpu/nvgpu/common/ltc/ltc_gp10b.c b/drivers/gpu/nvgpu/common/ltc/ltc_gp10b.c
index e678d198c..08e6f20d3 100644
--- a/drivers/gpu/nvgpu/common/ltc/ltc_gp10b.c
+++ b/drivers/gpu/nvgpu/common/ltc/ltc_gp10b.c
@@ -260,7 +260,9 @@ void gp10b_ltc_lts_isr(struct gk20a *g,	unsigned int ltc, unsigned int slice)
 		nvgpu_writel_check(g,
 			ltc_ltc0_lts0_dstg_ecc_report_r() + offset,
 			ecc_stats_reg_val);
-		g->ops.mm.l2_flush(g, true);
+		if (g->ops.mm.l2_flush(g, true) != 0) {
+			nvgpu_err(g, "l2_flush failed");
+		}
 	}
 	if ((ltc_intr &
 	     ltc_ltcs_ltss_intr_ecc_ded_error_pending_f()) != 0U) {
diff --git a/drivers/gpu/nvgpu/common/mm/gmmu/page_table.c b/drivers/gpu/nvgpu/common/mm/gmmu/page_table.c
index 2b0d0b959..0e4d55e97 100644
--- a/drivers/gpu/nvgpu/common/mm/gmmu/page_table.c
+++ b/drivers/gpu/nvgpu/common/mm/gmmu/page_table.c
@@ -891,11 +891,15 @@ void gk20a_locked_gmmu_unmap(struct vm_gk20a *vm,
 	}
 
 	if (batch == NULL) {
-		gk20a_mm_l2_flush(g, true);
+		if (gk20a_mm_l2_flush(g, true) != 0) {
+			nvgpu_err(g, "gk20a_mm_l2_flush[1] failed");
+		}
 		g->ops.fb.tlb_invalidate(g, vm->pdb.mem);
 	} else {
 		if (!batch->gpu_l2_flushed) {
-			gk20a_mm_l2_flush(g, true);
+			if (gk20a_mm_l2_flush(g, true) != 0) {
+				nvgpu_err(g, "gk20a_mm_l2_flush[2] failed");
+			}
 			batch->gpu_l2_flushed = true;
 		}
 		batch->need_tlb_invalidate = true;
diff --git a/drivers/gpu/nvgpu/common/mm/mm.c b/drivers/gpu/nvgpu/common/mm/mm.c
index 6cd92809a..b90a90c07 100644
--- a/drivers/gpu/nvgpu/common/mm/mm.c
+++ b/drivers/gpu/nvgpu/common/mm/mm.c
@@ -116,12 +116,18 @@ u32 nvgpu_vm_get_pte_size(struct vm_gk20a *vm, u64 base, u64 size)
 
 int nvgpu_mm_suspend(struct gk20a *g)
 {
+	int err;
+
 	nvgpu_log_info(g, "MM suspend running...");
 
 	nvgpu_vidmem_thread_pause_sync(&g->mm);
 
 	g->ops.mm.cbc_clean(g);
-	g->ops.mm.l2_flush(g, false);
+	err = g->ops.mm.l2_flush(g, false);
+	if (err != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		return err;
+	}
 
 	if (g->ops.fb.disable_hub_intr != NULL) {
 		g->ops.fb.disable_hub_intr(g);
@@ -133,7 +139,7 @@ int nvgpu_mm_suspend(struct gk20a *g)
 
 	nvgpu_log_info(g, "MM suspend done!");
 
-	return 0;
+	return err;
 }
 
 u64 nvgpu_inst_block_addr(struct gk20a *g, struct nvgpu_mem *inst_block)
diff --git a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
index fb0897b87..395243b55 100644
--- a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
@@ -81,14 +81,17 @@ static void gr_gk20a_enable_elcg(struct gk20a *g);
 
 u32 gr_gk20a_get_ctx_id(struct gk20a *g, struct nvgpu_mem *ctx_mem)
 {
-	u32 ctx_id;
+	/* Initialize ctx_id to invalid value */
+	u32 ctx_id = 0;
 
 	/* Channel gr_ctx buffer is gpu cacheable.
 	   Flush and invalidate before cpu update. */
-	g->ops.mm.l2_flush(g, true);
-
-	ctx_id = g->ops.gr.ctxsw_prog.get_main_image_ctx_id(g, ctx_mem);
-	nvgpu_log(g, gpu_dbg_fn | gpu_dbg_intr, "ctx_id: 0x%x", ctx_id);
+	if (g->ops.mm.l2_flush(g, true) != 0) {
+		nvgpu_err(g, "l2_flush failed");
+	} else {
+		ctx_id = g->ops.gr.ctxsw_prog.get_main_image_ctx_id(g, ctx_mem);
+		nvgpu_log(g, gpu_dbg_fn | gpu_dbg_intr, "ctx_id: 0x%x", ctx_id);
+	}
 	return ctx_id;
 }
 
@@ -1394,7 +1397,11 @@ restore_fe_go_idle:
 		goto clean_up;
 	}
 
-	g->ops.mm.l2_flush(g, true);
+	err = g->ops.mm.l2_flush(g, true);
+	if (err != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		goto clean_up;
+	}
 	g->ops.gr.ctxsw_prog.set_zcull_mode_no_ctxsw(g, gr_mem);
 
 	g->ops.gr.ctxsw_prog.set_zcull_ptr(g, gr_mem, 0);
@@ -1462,7 +1469,11 @@ int gr_gk20a_update_smpc_ctxsw_mode(struct gk20a *g,
 
 	/* Channel gr_ctx buffer is gpu cacheable.
 	   Flush and invalidate before cpu update. */
-	g->ops.mm.l2_flush(g, true);
+	ret = g->ops.mm.l2_flush(g, true);
+	if (ret != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		goto out;
+	}
 
 	g->ops.gr.ctxsw_prog.set_pm_smpc_mode(g, mem, enable_smpc_ctxsw);
 
@@ -1546,7 +1557,11 @@ int gr_gk20a_update_hwpm_ctxsw_mode(struct gk20a *g,
 
 	/* Channel gr_ctx buffer is gpu cacheable.
 	   Flush and invalidate before cpu update. */
-	g->ops.mm.l2_flush(g, true);
+	ret = g->ops.mm.l2_flush(g, true);
+	if (ret != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		return ret;
+	}
 
 	if (mode != NVGPU_DBG_HWPM_CTXSW_MODE_NO_CTXSW) {
 		/* Allocate buffer if necessary */
@@ -7404,7 +7419,11 @@ int __gr_gk20a_exec_ctx_ops(struct channel_gk20a *ch,
 		goto cleanup;
 	}
 
-	g->ops.mm.l2_flush(g, true);
+	err = g->ops.mm.l2_flush(g, true);
+	if (err != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		goto cleanup;
+	}
 
 	/* write to appropriate place in context image,
 	 * first have to figure out where that really is */
diff --git a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
index ce2ce77cb..7ca07fc6b 100644
--- a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
@@ -553,12 +553,13 @@ void gk20a_mm_l2_invalidate(struct gk20a *g)
 	gk20a_idle_nosuspend(g);
 }
 
-void gk20a_mm_l2_flush(struct gk20a *g, bool invalidate)
+int gk20a_mm_l2_flush(struct gk20a *g, bool invalidate)
 {
 	struct mm_gk20a *mm = &g->mm;
 	u32 data;
 	struct nvgpu_timeout timeout;
 	u32 retries = 2000;
+	int err = -ETIMEDOUT;
 
 	nvgpu_log_fn(g, " ");
 
@@ -592,6 +593,7 @@ void gk20a_mm_l2_flush(struct gk20a *g, bool invalidate)
 				nvgpu_log_info(g, "l2_flush_dirty 0x%x", data);
 				nvgpu_udelay(5);
 		} else {
+			err = 0;
 			break;
 		}
 	} while (nvgpu_timeout_expired_msg(&timeout,
@@ -607,6 +609,8 @@ void gk20a_mm_l2_flush(struct gk20a *g, bool invalidate)
 
 hw_was_off:
 	gk20a_idle_nosuspend(g);
+
+	return err;
 }
 
 void gk20a_mm_cbc_clean(struct gk20a *g)
diff --git a/drivers/gpu/nvgpu/gk20a/mm_gk20a.h b/drivers/gpu/nvgpu/gk20a/mm_gk20a.h
index 26290e79b..7440d2422 100644
--- a/drivers/gpu/nvgpu/gk20a/mm_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/mm_gk20a.h
@@ -73,7 +73,7 @@ struct gk20a;
 struct channel_gk20a;
 
 int gk20a_mm_fb_flush(struct gk20a *g);
-void gk20a_mm_l2_flush(struct gk20a *g, bool invalidate);
+int gk20a_mm_l2_flush(struct gk20a *g, bool invalidate);
 void gk20a_mm_cbc_clean(struct gk20a *g);
 void gk20a_mm_l2_invalidate(struct gk20a *g);
 
diff --git a/drivers/gpu/nvgpu/gv11b/mm_gv11b.c b/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
index 21f5d5e51..3a69944a3 100644
--- a/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
+++ b/drivers/gpu/nvgpu/gv11b/mm_gv11b.c
@@ -203,18 +203,38 @@ int gv11b_init_mm_setup_hw(struct gk20a *g)
 	return err;
 }
 
-void gv11b_mm_l2_flush(struct gk20a *g, bool invalidate)
+int gv11b_mm_l2_flush(struct gk20a *g, bool invalidate)
 {
+	int err = 0;
+
 	nvgpu_log(g, gpu_dbg_fn, "gv11b_mm_l2_flush");
 
-	g->ops.mm.fb_flush(g);
-	gk20a_mm_l2_flush(g, invalidate);
-	if (g->ops.bus.bar1_bind != NULL) {
-		g->ops.fb.tlb_invalidate(g,
-				g->mm.bar1.vm->pdb.mem);
-	} else {
-		g->ops.mm.fb_flush(g);
+	err = g->ops.mm.fb_flush(g);
+	if (err != 0) {
+		nvgpu_err(g, "mm.fb_flush()[1] failed err=%d", err);
+		return err;
 	}
+	err = gk20a_mm_l2_flush(g, invalidate);
+	if (err != 0) {
+		nvgpu_err(g, "gk20a_mm_l2_flush failed");
+		return err;
+	}
+	if (g->ops.bus.bar1_bind != NULL) {
+		err = g->ops.fb.tlb_invalidate(g,
+				g->mm.bar1.vm->pdb.mem);
+		if (err != 0) {
+			nvgpu_err(g, "fb.tlb_invalidate() failed err=%d", err);
+			return err;
+		}
+	} else {
+		err = g->ops.mm.fb_flush(g);
+		if (err != 0) {
+			nvgpu_err(g, "mm.fb_flush()[2] failed err=%d", err);
+			return err;
+		}
+	}
+
+	return err;
 }
 
 /*
diff --git a/drivers/gpu/nvgpu/gv11b/mm_gv11b.h b/drivers/gpu/nvgpu/gv11b/mm_gv11b.h
index ba2470888..3b9ceb837 100644
--- a/drivers/gpu/nvgpu/gv11b/mm_gv11b.h
+++ b/drivers/gpu/nvgpu/gv11b/mm_gv11b.h
@@ -33,7 +33,7 @@ void gv11b_init_inst_block(struct nvgpu_mem *inst_block,
 		struct vm_gk20a *vm, u32 big_page_size);
 bool gv11b_mm_mmu_fault_pending(struct gk20a *g);
 int gv11b_init_mm_setup_hw(struct gk20a *g);
-void gv11b_mm_l2_flush(struct gk20a *g, bool invalidate);
+int gv11b_mm_l2_flush(struct gk20a *g, bool invalidate);
 u64 gv11b_gpu_phys_addr(struct gk20a *g,
 			struct nvgpu_gmmu_attrs *attrs, u64 phys);
 void gv11b_mm_fault_info_mem_destroy(struct gk20a *g);
diff --git a/drivers/gpu/nvgpu/gv11b/subctx_gv11b.c b/drivers/gpu/nvgpu/gv11b/subctx_gv11b.c
index 585543c7d..85096c441 100644
--- a/drivers/gpu/nvgpu/gv11b/subctx_gv11b.c
+++ b/drivers/gpu/nvgpu/gv11b/subctx_gv11b.c
@@ -102,6 +102,7 @@ int gv11b_update_subctx_header(struct channel_gk20a *c, u64 gpu_va)
 	struct gk20a *g = c->g;
 	struct tsg_gk20a *tsg;
 	struct nvgpu_gr_ctx *gr_ctx;
+	int err = 0;
 
 	tsg = tsg_gk20a_from_ch(c);
 	if (tsg == NULL) {
@@ -110,7 +111,11 @@ int gv11b_update_subctx_header(struct channel_gk20a *c, u64 gpu_va)
 
 	gr_ctx = tsg->gr_ctx;
 
-	g->ops.mm.l2_flush(g, true);
+	err = g->ops.mm.l2_flush(g, true);
+	if (err != 0) {
+		nvgpu_err(g, "l2_flush failed");
+		return err;
+	}
 
 	/* set priv access map */
 	g->ops.gr.ctxsw_prog.set_priv_access_map_addr(g, ctxheader,
@@ -129,7 +134,7 @@ int gv11b_update_subctx_header(struct channel_gk20a *c, u64 gpu_va)
 
 	g->ops.gr.ctxsw_prog.set_type_per_veid_header(g, ctxheader);
 
-	return 0;
+	return err;
 }
 
 static void gv11b_subctx_commit_valid_mask(struct vm_gk20a *vm,
diff --git a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
index 902f3c986..7977e36b0 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
@@ -1094,7 +1094,7 @@ struct gpu_ops {
 				struct channel_gk20a *ch);
 		int (*fb_flush)(struct gk20a *g);
 		void (*l2_invalidate)(struct gk20a *g);
-		void (*l2_flush)(struct gk20a *g, bool invalidate);
+		int (*l2_flush)(struct gk20a *g, bool invalidate);
 		void (*cbc_clean)(struct gk20a *g);
 		void (*set_big_page_size)(struct gk20a *g,
 					  struct nvgpu_mem *mem, u32 size);
diff --git a/drivers/gpu/nvgpu/os/linux/ioctl_ctrl.c b/drivers/gpu/nvgpu/os/linux/ioctl_ctrl.c
index 2c0292a01..3b364c7d7 100644
--- a/drivers/gpu/nvgpu/os/linux/ioctl_ctrl.c
+++ b/drivers/gpu/nvgpu/os/linux/ioctl_ctrl.c
@@ -607,11 +607,17 @@ static int nvgpu_gpu_ioctl_l2_fb_ops(struct gk20a *g,
 	    (!args->l2_flush && args->l2_invalidate))
 		return -EINVAL;
 
-	if (args->l2_flush)
-		g->ops.mm.l2_flush(g, args->l2_invalidate ? true : false);
+	if (args->l2_flush) {
+		err = g->ops.mm.l2_flush(g, args->l2_invalidate ? true : false);
+		if (err != 0) {
+			nvgpu_err(g, "l2_flush failed");
+			return err;
+		}
+	}
 
-	if (args->fb_flush)
+	if (args->fb_flush) {
 		g->ops.mm.fb_flush(g);
+	}
 
 	return err;
 }
diff --git a/drivers/gpu/nvgpu/vgpu/mm_vgpu.c b/drivers/gpu/nvgpu/vgpu/mm_vgpu.c
index 78709ed64..cdc231cae 100644
--- a/drivers/gpu/nvgpu/vgpu/mm_vgpu.c
+++ b/drivers/gpu/nvgpu/vgpu/mm_vgpu.c
@@ -224,7 +224,7 @@ int vgpu_vm_bind_channel(struct vm_gk20a *vm,
 	return err;
 }
 
-static void vgpu_cache_maint(u64 handle, u8 op)
+static int vgpu_cache_maint(u64 handle, u8 op)
 {
 	struct tegra_vgpu_cmd_msg msg;
 	struct tegra_vgpu_cache_maint_params *p = &msg.params.cache_maint;
@@ -235,6 +235,7 @@ static void vgpu_cache_maint(u64 handle, u8 op)
 	p->op = op;
 	err = vgpu_comm_sendrecv(&msg, sizeof(msg), sizeof(msg));
 	WARN_ON(err || msg.ret);
+	return err;
 }
 
 int vgpu_mm_fb_flush(struct gk20a *g)
@@ -242,8 +243,7 @@ int vgpu_mm_fb_flush(struct gk20a *g)
 
 	nvgpu_log_fn(g, " ");
 
-	vgpu_cache_maint(vgpu_get_handle(g), TEGRA_VGPU_FB_FLUSH);
-	return 0;
+	return vgpu_cache_maint(vgpu_get_handle(g), TEGRA_VGPU_FB_FLUSH);
 }
 
 void vgpu_mm_l2_invalidate(struct gk20a *g)
@@ -251,10 +251,10 @@ void vgpu_mm_l2_invalidate(struct gk20a *g)
 
 	nvgpu_log_fn(g, " ");
 
-	vgpu_cache_maint(vgpu_get_handle(g), TEGRA_VGPU_L2_MAINT_INV);
+	(void) vgpu_cache_maint(vgpu_get_handle(g), TEGRA_VGPU_L2_MAINT_INV);
 }
 
-void vgpu_mm_l2_flush(struct gk20a *g, bool invalidate)
+int vgpu_mm_l2_flush(struct gk20a *g, bool invalidate)
 {
 	u8 op;
 
@@ -265,7 +265,7 @@ void vgpu_mm_l2_flush(struct gk20a *g, bool invalidate)
 	else
 		op =  TEGRA_VGPU_L2_MAINT_FLUSH;
 
-	vgpu_cache_maint(vgpu_get_handle(g), op);
+	return vgpu_cache_maint(vgpu_get_handle(g), op);
 }
 
 int vgpu_mm_tlb_invalidate(struct gk20a *g, struct nvgpu_mem *pdb)
diff --git a/drivers/gpu/nvgpu/vgpu/mm_vgpu.h b/drivers/gpu/nvgpu/vgpu/mm_vgpu.h
index 491700fc0..1f4291db8 100644
--- a/drivers/gpu/nvgpu/vgpu/mm_vgpu.h
+++ b/drivers/gpu/nvgpu/vgpu/mm_vgpu.h
@@ -42,7 +42,7 @@ int vgpu_vm_bind_channel(struct vm_gk20a *vm,
 				struct channel_gk20a *ch);
 int vgpu_mm_fb_flush(struct gk20a *g);
 void vgpu_mm_l2_invalidate(struct gk20a *g);
-void vgpu_mm_l2_flush(struct gk20a *g, bool invalidate);
+int vgpu_mm_l2_flush(struct gk20a *g, bool invalidate);
 int vgpu_mm_tlb_invalidate(struct gk20a *g, struct nvgpu_mem *pdb);
 void vgpu_mm_mmu_set_debug_mode(struct gk20a *g, bool enable);
 #endif