accel/ivpu: Add support for hardware fault injection

Introduces the capability to simulate hardware faults for testing
purposes. The new `fail_hw` fault can be injected in
`ivpu_hw_reg_poll_fld()`, which is used in various parts of the driver
to wait for the hardware to reach a specific state. This allows to test
failures during NPU boot and shutdown, IPC message handling and more.

Fault injection can be enabled using debugfs or a module parameter.

Reviewed-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250129125636.1047413-2-jacek.lawrynowicz@linux.intel.com

diff --git a/drivers/accel/ivpu/ivpu_debugfs.c b/drivers/accel/ivpu/ivpu_debugfs.c
index 8180b95ed69dc79c1af4971e4f13b249bcb8fa30..e79715c53f2a084062f9050dad8d825dc4200976 100644 (file)
--- a/drivers/accel/ivpu/ivpu_debugfs.c
+++ b/drivers/accel/ivpu/ivpu_debugfs.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/debugfs.h>
+#include <linux/fault-inject.h>
 
 #include <drm/drm_debugfs.h>
 #include <drm/drm_file.h>
@@ -430,4 +431,8 @@ void ivpu_debugfs_init(struct ivpu_device *vdev)
                                    debugfs_root, vdev, &fw_profiling_freq_fops);
                debugfs_create_file("dct", 0644, debugfs_root, vdev, &ivpu_dct_fops);
        }
+
+#ifdef CONFIG_FAULT_INJECTION
+       fault_create_debugfs_attr("fail_hw", debugfs_root, &ivpu_hw_failure);
+#endif
 }

diff --git a/drivers/accel/ivpu/ivpu_hw.c b/drivers/accel/ivpu/ivpu_hw.c
index e332f19ab51de121c414cab781a62bfe1922983c..8099ab047bfe611a5dc0af42200d42d390b9cc49 100644 (file)
--- a/drivers/accel/ivpu/ivpu_hw.c
+++ b/drivers/accel/ivpu/ivpu_hw.c
@@ -9,6 +9,15 @@
 #include "ivpu_hw_ip.h"
 
 #include <linux/dmi.h>
+#include <linux/fault-inject.h>
+
+#ifdef CONFIG_FAULT_INJECTION
+DECLARE_FAULT_ATTR(ivpu_hw_failure);
+
+static char *ivpu_fail_hw;
+module_param_named_unsafe(fail_hw, ivpu_fail_hw, charp, 0444);
+MODULE_PARM_DESC(fail_hw, "<interval>,<probability>,<space>,<times>");
+#endif
 
 static char *platform_to_str(u32 platform)
 {
@@ -247,6 +256,11 @@ int ivpu_hw_init(struct ivpu_device *vdev)
        timeouts_init(vdev);
        atomic_set(&vdev->hw->firewall_irq_counter, 0);
 
+#ifdef CONFIG_FAULT_INJECTION
+       if (ivpu_fail_hw)
+               setup_fault_attr(&ivpu_hw_failure, ivpu_fail_hw);
+#endif
+
        return 0;
 }
 

diff --git a/drivers/accel/ivpu/ivpu_hw_ip.c b/drivers/accel/ivpu/ivpu_hw_ip.c
index 029dd065614b2ba8475da17e99e1734f8f8dd915..823f6a57dc54681f70bf22260a28e1fd0df7456f 100644 (file)
--- a/drivers/accel/ivpu/ivpu_hw_ip.c
+++ b/drivers/accel/ivpu/ivpu_hw_ip.c
@@ -968,14 +968,14 @@ void ivpu_hw_ip_wdt_disable(struct ivpu_device *vdev)
 
 static u32 ipc_rx_count_get_37xx(struct ivpu_device *vdev)
 {
-       u32 count = REGV_RD32_SILENT(VPU_37XX_HOST_SS_TIM_IPC_FIFO_STAT);
+       u32 count = readl(vdev->regv + VPU_37XX_HOST_SS_TIM_IPC_FIFO_STAT);
 
        return REG_GET_FLD(VPU_37XX_HOST_SS_TIM_IPC_FIFO_STAT, FILL_LEVEL, count);
 }
 
 static u32 ipc_rx_count_get_40xx(struct ivpu_device *vdev)
 {
-       u32 count = REGV_RD32_SILENT(VPU_40XX_HOST_SS_TIM_IPC_FIFO_STAT);
+       u32 count = readl(vdev->regv + VPU_40XX_HOST_SS_TIM_IPC_FIFO_STAT);
 
        return REG_GET_FLD(VPU_40XX_HOST_SS_TIM_IPC_FIFO_STAT, FILL_LEVEL, count);
 }

diff --git a/drivers/accel/ivpu/ivpu_hw_reg_io.h b/drivers/accel/ivpu/ivpu_hw_reg_io.h
index 79b3f441eac4daa500a1ce6ea9999e8bc529ea99..66259b0ead0269ea9db77cbb9a1f46019b2e96e6 100644 (file)
--- a/drivers/accel/ivpu/ivpu_hw_reg_io.h
+++ b/drivers/accel/ivpu/ivpu_hw_reg_io.h
@@ -7,6 +7,7 @@
 #define __IVPU_HW_REG_IO_H__
 
 #include <linux/bitfield.h>
+#include <linux/fault-inject.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 
@@ -16,13 +17,11 @@
 #define REG_IO_ERROR      0xffffffff
 
 #define REGB_RD32(reg)          ivpu_hw_reg_rd32(vdev, vdev->regb, (reg), #reg, __func__)
-#define REGB_RD32_SILENT(reg)   readl(vdev->regb + (reg))
 #define REGB_RD64(reg)          ivpu_hw_reg_rd64(vdev, vdev->regb, (reg), #reg, __func__)
 #define REGB_WR32(reg, val)     ivpu_hw_reg_wr32(vdev, vdev->regb, (reg), (val), #reg, __func__)
 #define REGB_WR64(reg, val)     ivpu_hw_reg_wr64(vdev, vdev->regb, (reg), (val), #reg, __func__)
 
 #define REGV_RD32(reg)          ivpu_hw_reg_rd32(vdev, vdev->regv, (reg), #reg, __func__)
-#define REGV_RD32_SILENT(reg)   readl(vdev->regv + (reg))
 #define REGV_RD64(reg)          ivpu_hw_reg_rd64(vdev, vdev->regv, (reg), #reg, __func__)
 #define REGV_WR32(reg, val)     ivpu_hw_reg_wr32(vdev, vdev->regv, (reg), (val), #reg, __func__)
 #define REGV_WR64(reg, val)     ivpu_hw_reg_wr64(vdev, vdev->regv, (reg), (val), #reg, __func__)
@@ -47,31 +46,42 @@
 #define REG_TEST_FLD_NUM(REG, FLD, num, val) \
        ((num) == FIELD_GET(REG##_##FLD##_MASK, val))
 
-#define REGB_POLL_FLD(reg, fld, val, timeout_us) \
-({ \
-       u32 var; \
-       int r; \
-       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) Polling field %s started (expected 0x%x)\n", \
-                __func__, #reg, reg, #fld, val); \
-       r = read_poll_timeout(REGB_RD32_SILENT, var, (FIELD_GET(reg##_##fld##_MASK, var) == (val)),\
-                             REG_POLL_SLEEP_US, timeout_us, false, (reg)); \
-       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) Polling field %s %s (reg val 0x%08x)\n", \
-                __func__, #reg, reg, #fld, r ? "ETIMEDOUT" : "OK", var); \
-       r; \
-})
-
-#define REGV_POLL_FLD(reg, fld, val, timeout_us) \
-({ \
-       u32 var; \
-       int r; \
-       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) Polling field %s started (expected 0x%x)\n", \
-                __func__, #reg, reg, #fld, val); \
-       r = read_poll_timeout(REGV_RD32_SILENT, var, (FIELD_GET(reg##_##fld##_MASK, var) == (val)),\
-                             REG_POLL_SLEEP_US, timeout_us, false, (reg)); \
-       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) Polling field %s %s (reg val 0x%08x)\n", \
-                __func__, #reg, reg, #fld, r ? "ETIMEDOUT" : "OK", var); \
-       r; \
-})
+#define REGB_POLL_FLD(reg, fld, exp_fld_val, timeout_us) \
+       ivpu_hw_reg_poll_fld(vdev, vdev->regb, reg, reg##_##fld##_MASK, \
+                            FIELD_PREP(reg##_##fld##_MASK, exp_fld_val), timeout_us, \
+                            __func__, #reg, #fld)
+
+#define REGV_POLL_FLD(reg, fld, exp_fld_val, timeout_us) \
+       ivpu_hw_reg_poll_fld(vdev, vdev->regv, reg, reg##_##fld##_MASK, \
+                            FIELD_PREP(reg##_##fld##_MASK, exp_fld_val), timeout_us, \
+                            __func__, #reg, #fld)
+
+extern struct fault_attr ivpu_hw_failure;
+
+static inline int __must_check
+ivpu_hw_reg_poll_fld(struct ivpu_device *vdev, void __iomem *base,
+                    u32 reg_offset, u32 reg_mask, u32 exp_masked_val, u32 timeout_us,
+                    const char *func_name, const char *reg_name, const char *fld_name)
+{
+       u32 reg_val;
+       int ret;
+
+       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) POLL %s started (exp_val 0x%x)\n",
+                func_name, reg_name, reg_offset, fld_name, exp_masked_val);
+
+       ret = read_poll_timeout(readl, reg_val, (reg_val & reg_mask) == exp_masked_val,
+                               REG_POLL_SLEEP_US, timeout_us, false, base + reg_offset);
+
+#ifdef CONFIG_FAULT_INJECTION
+       if (should_fail(&ivpu_hw_failure, 1))
+               ret = -ETIMEDOUT;
+#endif
+
+       ivpu_dbg(vdev, REG, "%s : %s (0x%08x) POLL %s %s (reg_val 0x%08x)\n",
+                func_name, reg_name, reg_offset, fld_name, ret ? "ETIMEDOUT" : "OK", reg_val);
+
+       return ret;
+}
 
 static inline u32
 ivpu_hw_reg_rd32(struct ivpu_device *vdev, void __iomem *base, u32 reg,