gpu: nvgpu: debugfs node to enable/disable ltc_illegal_compstat intr

Added debugfs node under ltc directory with name:
intr_illegal_compstat_enable

Enabling/disabling of ltc_illegal_compstat intr is
possible through debugfs node.

Since ltc state is lost with rail gate, this setting is
cached and will be populated during ltc initialization.

Bug 2099406

Change-Id: I4bf62228dfd2bbb94f87f923f9f4f6e5ad0b07f0
Signed-off-by: seshendra Gadagottu <sgadagottu@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1774683
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

4 files changed, 117 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/os/linux/debug.c b/drivers/gpu/nvgpu/os/linux/debug.c
index c4dae9e6..9403e72e 100644
--- a/drivers/gpu/nvgpu/os/linux/debug.c
+++ b/drivers/gpu/nvgpu/os/linux/debug.c
@@ -22,6 +22,7 @@
 #include "debug_sched.h"
 #include "debug_hal.h"
 #include "debug_xve.h"
+#include "debug_ltc.h"
 #include "debug_bios.h"
 #include "os_linux.h"
 #include "platform_gk20a.h"
@@ -435,6 +436,7 @@ void gk20a_debug_init(struct gk20a *g, const char *debugfs_symlink)
 #ifdef CONFIG_NVGPU_TRACK_MEM_USAGE
         nvgpu_kmem_debugfs_init(g);
 #endif
+        nvgpu_ltc_debugfs_init(g);
         if (g->pci_vendor_id) {
                 nvgpu_xve_debugfs_init(g);
                 nvgpu_bios_debugfs_init(g);
diff --git a/drivers/gpu/nvgpu/os/linux/debug_ltc.c b/drivers/gpu/nvgpu/os/linux/debug_ltc.c
new file mode 100644
index 00000000..88fb45f4
--- /dev/null
+++ b/drivers/gpu/nvgpu/os/linux/debug_ltc.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2018 NVIDIA Corporation.  All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include "debug_ltc.h"
+#include "os_linux.h"
+#include "gk20a/gk20a.h"
+
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+
+static ssize_t ltc_intr_illegal_compstat_read(struct file *file,
+                        char __user *user_buf, size_t count, loff_t *ppos)
+{
+        char buf[3];
+        struct gk20a *g = file->private_data;
+
+        if (g->ltc_intr_en_illegal_compstat)
+                buf[0] = 'Y';
+        else
+                buf[0] = 'N';
+        buf[1] = '\n';
+        buf[2] = 0x00;
+
+        return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
+}
+
+static ssize_t ltc_intr_illegal_compstat_write(struct file *file,
+                        const char __user *user_buf, size_t count, loff_t *ppos)
+{
+        char buf[3];
+        int buf_size;
+        bool intr_illegal_compstat_enabled;
+        struct gk20a *g = file->private_data;
+        int err;
+
+        if (!g->ops.ltc.intr_en_illegal_compstat)
+                return -EINVAL;
+
+        buf_size = min(count, (sizeof(buf)-1));
+        if (copy_from_user(buf, user_buf, buf_size))
+                return -EFAULT;
+
+        err = gk20a_busy(g);
+        if (err)
+                return err;
+
+        if (strtobool(buf, &intr_illegal_compstat_enabled) == 0) {
+                g->ops.ltc.intr_en_illegal_compstat(g,
+                                intr_illegal_compstat_enabled);
+                g->ltc_intr_en_illegal_compstat = intr_illegal_compstat_enabled;
+        }
+
+        gk20a_idle(g);
+
+        return buf_size;
+}
+
+static const struct file_operations ltc_intr_illegal_compstat_fops = {
+        .open = simple_open,
+        .read = ltc_intr_illegal_compstat_read,
+        .write = ltc_intr_illegal_compstat_write,
+};
+
+int nvgpu_ltc_debugfs_init(struct gk20a *g)
+{
+        struct dentry *d;
+        struct nvgpu_os_linux *l = nvgpu_os_linux_from_gk20a(g);
+        struct dentry *gpu_root = l->debugfs;
+
+        l->debugfs_ltc = debugfs_create_dir("ltc", gpu_root);
+        if (IS_ERR_OR_NULL(l->debugfs_ltc))
+                return -ENODEV;
+
+        /* Debug fs node to enable/disable illegal_compstat */
+        d = debugfs_create_file("intr_illegal_compstat_enable", 0600,
+                            l->debugfs_ltc, g,
+                            &ltc_intr_illegal_compstat_fops);
+        if (!d)
+                return -ENOMEM;
+
+        return 0;
+}
diff --git a/drivers/gpu/nvgpu/os/linux/debug_ltc.h b/drivers/gpu/nvgpu/os/linux/debug_ltc.h
new file mode 100644
index 00000000..3ad734ce
--- /dev/null
+++ b/drivers/gpu/nvgpu/os/linux/debug_ltc.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2018 NVIDIA Corporation.  All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __NVGPU_DEBUG_LTC_H__
+#define __NVGPU_DEBUG_LTC_H__
+
+struct gk20a;
+int nvgpu_ltc_debugfs_init(struct gk20a *g);
+
+#endif /* __NVGPU_DEBUG_LTC_H__ */
diff --git a/drivers/gpu/nvgpu/os/linux/os_linux.h b/drivers/gpu/nvgpu/os/linux/os_linux.h
index 85d697bd..13c20a81 100644
--- a/drivers/gpu/nvgpu/os/linux/os_linux.h
+++ b/drivers/gpu/nvgpu/os/linux/os_linux.h
@@ -135,6 +135,7 @@ struct nvgpu_os_linux {
         struct dentry *debugfs_xve;
         struct dentry *debugfs_kmem;
         struct dentry *debugfs_hal;
+        struct dentry *debugfs_ltc;
 
         struct dentry *debugfs_force_preemption_cilp;
         struct dentry *debugfs_force_preemption_gfxp;