media: venus: Add support for SSR trigger using fault injection

Here we introduce a new fault injection for SSR trigger.

To trigger the SSR:
 echo 100 >  /sys/kernel/debug/venus/fail_ssr/probability
 echo 1 >  /sys/kernel/debug/venus/fail_ssr/times
Co-developed-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/qcom/venus/core.c

@@ -265,6 +265,19 @@ static void venus_assign_register_offsets(struct venus_core *core)
 	}
 }
 
+static irqreturn_t venus_isr_thread(int irq, void *dev_id)
+{
+	struct venus_core *core = dev_id;
+	irqreturn_t ret;
+
+	ret = hfi_isr_thread(irq, dev_id);
+
+	if (ret == IRQ_HANDLED && venus_fault_inject_ssr())
+		hfi_core_trigger_ssr(core, HFI_TEST_SSR_SW_ERR_FATAL);
+
+	return ret;
+}
+
 static int venus_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -320,7 +333,7 @@ static int venus_probe(struct platform_device *pdev)
 	INIT_DELAYED_WORK(&core->work, venus_sys_error_handler);
 	init_waitqueue_head(&core->sys_err_done);
 
-	ret = devm_request_threaded_irq(dev, core->irq, hfi_isr, hfi_isr_thread,
+	ret = devm_request_threaded_irq(dev, core->irq, hfi_isr, venus_isr_thread,
 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 					"venus", core);
 	if (ret)

drivers/media/platform/qcom/venus/dbgfs.c

@@ -4,13 +4,22 @@
  */
 
 #include <linux/debugfs.h>
+#include <linux/fault-inject.h>
 
 #include "core.h"
 
+#ifdef CONFIG_FAULT_INJECTION
+DECLARE_FAULT_ATTR(venus_ssr_attr);
+#endif
+
 void venus_dbgfs_init(struct venus_core *core)
 {
 	core->root = debugfs_create_dir("venus", NULL);
 	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
+
+#ifdef CONFIG_FAULT_INJECTION
+	fault_create_debugfs_attr("fail_ssr", core->root, &venus_ssr_attr);
+#endif
 }
 
 void venus_dbgfs_deinit(struct venus_core *core)

drivers/media/platform/qcom/venus/dbgfs.h

@@ -4,8 +4,21 @@
 #ifndef __VENUS_DBGFS_H__
 #define __VENUS_DBGFS_H__
 
+#include <linux/fault-inject.h>
+
 struct venus_core;
 
+#ifdef CONFIG_FAULT_INJECTION
+extern struct fault_attr venus_ssr_attr;
+static inline bool venus_fault_inject_ssr(void)
+{
+	return should_fail(&venus_ssr_attr, 1);
+}
+#else
+static inline bool venus_fault_inject_ssr(void) { return false; }
+#endif
+
+
 void venus_dbgfs_init(struct venus_core *core);
 void venus_dbgfs_deinit(struct venus_core *core);