drm/amdgpu: add amdgpu.ptl module parameter for PTL control

Add a new kernel module parameter 'amdgpu.ptl' to allow
users to enable or disable PTL feature at driver loading time.

Parameter values:
  *) 0 or -1: disable PTL (default)
  *) 1: enable PTL
  *) 2: permanently disable PTL

Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Reviewed-by: Yifan Zhang <yifan1.zhang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 25b80d4b097f63e1cae18b2eb596c9754d08d945..80b18bbd7f3a88fbb1de094853a8e0b5027030ce 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -267,6 +267,7 @@ extern int amdgpu_rebar;
 
 extern int amdgpu_wbrf;
 extern int amdgpu_user_queue;
+extern int amdgpu_ptl;
 
 extern uint amdgpu_hdmi_hpd_debounce_delay_ms;
 

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 60debd543e44eeabd856550beeb1bc1a288e6b34..99688391e70b011dada8663d313b66af0ed087b2 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -246,6 +246,7 @@ int amdgpu_umsch_mm_fwlog;
 int amdgpu_rebar = -1; /* auto */
 int amdgpu_user_queue = -1;
 uint amdgpu_hdmi_hpd_debounce_delay_ms;
+int amdgpu_ptl = -1; /* auto */
 
 DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
                        "DRM_UT_CORE",
@@ -1112,6 +1113,18 @@ module_param_named(user_queue, amdgpu_user_queue, int, 0444);
 MODULE_PARM_DESC(hdmi_hpd_debounce_delay_ms, "HDMI HPD disconnect debounce delay in milliseconds (0 to disable (by default), 1500 is common)");
 module_param_named(hdmi_hpd_debounce_delay_ms, amdgpu_hdmi_hpd_debounce_delay_ms, uint, 0644);
 
+/**
+ * DOC: ptl (int)
+ * Enable PTL feature at boot time. Possible values:
+ *
+ * - -1 = auto (ASIC specific default)
+ * -  0 = disable PTL (default)
+ * -  1 = enable PTL
+ * -  2 = permanently disable PTL (cannot be re-enabled at runtime)
+ */
+MODULE_PARM_DESC(ptl, "Enable PTL (-1 = auto, 0 = disable (default), 1 = enable, 2 = permanently disable)");
+module_param_named(ptl, amdgpu_ptl, int, 0444);
+
 /* These devices are not supported by amdgpu.
  * They are supported by the mach64, r128, radeon drivers
  */

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
index 78a9ce0eb60e4615e9fb0e25f2226d1ce577e3a6..9c588323e9b95d6b18c94ed374c3cf0d0cee8807 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
@@ -1300,6 +1300,9 @@ int amdgpu_ptl_perf_monitor_ctrl(struct amdgpu_device *adev, u32 req_code,
        psp = &adev->psp;
        ptl = &psp->ptl;
 
+       if (ptl->permanently_disabled && *ptl_state == 1)
+               return 0;
+
        if (amdgpu_ip_version(adev, GC_HWIP, 0) != IP_VERSION(9, 4, 4) ||
                        psp->sos.fw_version < 0x0036081a)
                return -EOPNOTSUPP;
@@ -1386,6 +1389,12 @@ static ssize_t ptl_enable_store(struct device *dev,
                return -EINVAL;
        }
 
+       /* Block enable when permanently disabled */
+       if (ptl->permanently_disabled) {
+               mutex_unlock(&ptl->mutex);
+               return -EPERM;
+       }
+
        fmt1 = ptl->fmt1;
        fmt2 = ptl->fmt2;
        ptl_state = enable ? 1 : 0;
@@ -1417,6 +1426,9 @@ static ssize_t ptl_enable_show(struct device *dev, struct device_attribute *attr
        struct amdgpu_device *adev = drm_to_adev(ddev);
        struct amdgpu_ptl *ptl = &adev->psp.ptl;
 
+       if (ptl->permanently_disabled)
+               return sysfs_emit(buf, "permanently disabled\n");
+
        return sysfs_emit(buf, "%s\n", ptl->enabled ? "enabled" : "disabled");
 }
 

diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c b/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
index aab6a4de54fa0c39ac418abd6d3a5839de9d576b..b59e944f7df0cb3b0da1fc6b59c525b121cff7a1 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
+++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
@@ -2405,6 +2405,32 @@ static int gfx_v9_4_3_perf_monitor_ptl_init(struct amdgpu_device *adev, bool ena
        return 0;
 }
 
+static int gfx_v9_4_3_ptl_hw_init(struct amdgpu_device *adev)
+{
+       struct amdgpu_ptl *ptl = &adev->psp.ptl;
+       bool enable;
+
+       switch (amdgpu_ptl) {
+       case 1:
+               enable = true;
+               break;
+       case 2:
+               /* Permanently disabled - cannot be re-enabled */
+               enable = false;
+               ptl->permanently_disabled = true;
+               break;
+       case -1:
+       case 0:
+       default:
+               enable = false;
+               break;
+       }
+
+       gfx_v9_4_3_perf_monitor_ptl_init(adev, enable ? 1 : 0);
+
+       return 0;
+}
+
 static int gfx_v9_4_3_hw_fini(struct amdgpu_ip_block *ip_block)
 {
        struct amdgpu_device *adev = ip_block->adev;
@@ -2587,7 +2613,7 @@ static int gfx_v9_4_3_late_init(struct amdgpu_ip_block *ip_block)
            adev->gfx.ras->enable_watchdog_timer)
                adev->gfx.ras->enable_watchdog_timer(adev);
 
-       gfx_v9_4_3_perf_monitor_ptl_init(adev, true);
+       gfx_v9_4_3_ptl_hw_init(adev);
 
        return 0;
 }

diff --git a/drivers/gpu/drm/amd/include/amdgpu_ptl.h b/drivers/gpu/drm/amd/include/amdgpu_ptl.h
index 568b6944e1ad12feede16f3e3265d1ceb5de7b9c..dc74119d91c8ced06991682b4f59c998b98278ad 100644 (file)
--- a/drivers/gpu/drm/amd/include/amdgpu_ptl.h
+++ b/drivers/gpu/drm/amd/include/amdgpu_ptl.h
@@ -44,6 +44,7 @@ struct amdgpu_ptl {
        enum amdgpu_ptl_fmt             fmt2;
        bool                            enabled;
        bool                            hw_supported;
+       bool                            permanently_disabled;
        /* PTL disable reference counting */
        atomic_t                        disable_ref;
        struct mutex                    mutex;