[PATCH v2 23/27] nvdimm/ocxl: Add debug IOCTLs

Alastair D'Silva
2019-12-03T03:48:47Z

From: Alastair D'Silva <alastair@d-silva.org>

These IOCTLs provide low level access to the card to aid in debugging
controller/FPGA firmware.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
---
drivers/nvdimm/ocxl/Kconfig | 6 +
drivers/nvdimm/ocxl/scm.c | 249 +++++++++++++++++++++++++++++++++
include/uapi/nvdimm/ocxl-scm.h | 32 +++++
3 files changed, 287 insertions(+)

diff --git a/drivers/nvdimm/ocxl/Kconfig b/drivers/nvdimm/ocxl/Kconfig
index 24099b300f5e..1df030cdd958 100644
--- a/drivers/nvdimm/ocxl/Kconfig
+++ b/drivers/nvdimm/ocxl/Kconfig
@@ -12,4 +12,10 @@ config OCXL_SCM

Select N if unsure.

+config OCXL_SCM_DEBUG
+ bool "OpenCAPI Storage Class Memory debugging"
+ depends on OCXL_SCM
+ help
+ Enables low level IOCTLs for OpenCAPI SCM firmware development
+
endif
diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
index e8b34262f397..a81eb5916eb3 100644
--- a/drivers/nvdimm/ocxl/scm.c
+++ b/drivers/nvdimm/ocxl/scm.c
@@ -1098,6 +1098,235 @@ int scm_req_controller_health_perf(struct scm_data *scm_data)
GLOBAL_MMIO_HCI_REQ_HEALTH_PERF);
}

+#ifdef CONFIG_OCXL_SCM_DEBUG
+/**
+ * scm_enable_fwdebug() - Enable FW debug on the controller
+ * @scm_data: a pointer to the SCM device data
+ * Return: 0 on success, negative on failure
+ */
+static int scm_enable_fwdebug(const struct scm_data *scm_data)
+{
+ return ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_HCI,
+ OCXL_LITTLE_ENDIAN,
+ GLOBAL_MMIO_HCI_FW_DEBUG);
+}
+
+/**
+ * scm_disable_fwdebug() - Disable FW debug on the controller
+ * @scm_data: a pointer to the SCM device data
+ * Return: 0 on success, negative on failure
+ */
+static int scm_disable_fwdebug(const struct scm_data *scm_data)
+{
+ return ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_HCIC,
+ OCXL_LITTLE_ENDIAN,
+ GLOBAL_MMIO_HCI_FW_DEBUG);
+}
+
+static int scm_ioctl_fwdebug(struct scm_data *scm_data,
+ struct scm_ioctl_fwdebug __user *uarg)
+{
+ struct scm_ioctl_fwdebug args;
+ u64 val;
+ int i;
+ int rc;
+
+ if (copy_from_user(&args, uarg, sizeof(args)))
+ return -EFAULT;
+
+ // Buffer size must be a multiple of 8
+ if ((args.buf_size & 0x07))
+ return -EINVAL;
+
+ if (args.buf_size > scm_data->admin_command.data_size)
+ return -EINVAL;
+
+ mutex_lock(&scm_data->admin_command.lock);
+
+ rc = scm_enable_fwdebug(scm_data);
+ if (rc)
+ goto out;
+
+ rc = scm_admin_command_request(scm_data, ADMIN_COMMAND_FW_DEBUG);
+ if (rc)
+ goto out;
+
+ // Write DebugAction & FunctionCode
+ val = ((u64)args.debug_action << 56) | ((u64)args.function_code << 40);
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu,
+ scm_data->admin_command.request_offset + 0x08,
+ OCXL_LITTLE_ENDIAN, val);
+ if (rc)
+ goto out;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu,
+ scm_data->admin_command.request_offset + 0x10,
+ OCXL_LITTLE_ENDIAN, args.debug_parameter_1);
+ if (rc)
+ goto out;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu,
+ scm_data->admin_command.request_offset + 0x18,
+ OCXL_LITTLE_ENDIAN, args.debug_parameter_2);
+ if (rc)
+ goto out;
+
+ for (i = 0x20; i < 0x38; i += 0x08)
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu,
+ scm_data->admin_command.request_offset + i,
+ OCXL_LITTLE_ENDIAN, 0);
+ if (rc)
+ goto out;
+
+
+ // Populate admin command buffer
+ if (args.buf_size) {
+ for (i = 0; i < args.buf_size; i += sizeof(u64)) {
+ u64 val;
+
+ if (copy_from_user(&val, &args.buf[i], sizeof(u64)))
+ return -EFAULT;
+
+ rc = ocxl_global_mmio_write64(scm_data->ocxl_afu,
+ scm_data->admin_command.data_offset + i,
+ OCXL_HOST_ENDIAN, val);
+ if (rc)
+ goto out;
+ }
+ }
+
+ rc = scm_admin_command_execute(scm_data);
+ if (rc)
+ goto out;
+
+ rc = scm_admin_command_complete_timeout(scm_data,
+ scm_data->timeouts[ADMIN_COMMAND_FW_DEBUG]);
+ if (rc < 0)
+ goto out;
+
+ rc = scm_admin_response(scm_data);
+ if (rc < 0)
+ goto out;
+ if (rc != STATUS_SUCCESS) {
+ scm_warn_status(scm_data, "Unexpected status from FW Debug", rc);
+ goto out;
+ }
+
+ if (args.buf_size) {
+ for (i = 0; i < args.buf_size; i += sizeof(u64)) {
+ u64 val;
+
+ rc = ocxl_global_mmio_read64(scm_data->ocxl_afu,
+ scm_data->admin_command.data_offset + i,
+ OCXL_HOST_ENDIAN, &val);
+ if (rc)
+ goto out;
+
+ if (copy_to_user(&args.buf[i], &val, sizeof(u64))) {
+ rc = -EFAULT;
+ goto out;
+ }
+ }
+ }
+
+ rc = scm_admin_response_handled(scm_data);
+ if (rc)
+ goto out;
+
+ rc = scm_disable_fwdebug(scm_data);
+ if (rc)
+ goto out;
+
+out:
+ mutex_unlock(&scm_data->admin_command.lock);
+ return rc;
+}
+
+static int scm_ioctl_shutdown(struct scm_data *scm_data)
+{
+ int rc;
+
+ mutex_lock(&scm_data->admin_command.lock);
+
+ rc = scm_admin_command_request(scm_data, ADMIN_COMMAND_SHUTDOWN);
+ if (rc)
+ goto out;
+
+ rc = scm_admin_command_execute(scm_data);
+ if (rc)
+ goto out;
+
+ rc = scm_admin_command_complete_timeout(scm_data, ADMIN_COMMAND_SHUTDOWN);
+ if (rc < 0) {
+ dev_warn(&scm_data->dev, "Shutdown timed out\n");
+ goto out;
+ }
+
+ rc = 0;
+ goto out;
+
+out:
+ mutex_unlock(&scm_data->admin_command.lock);
+ return rc;
+}
+
+static int scm_ioctl_mmio_write(struct scm_data *scm_data,
+ struct scm_ioctl_mmio __user *uarg)
+{
+ struct scm_ioctl_mmio args;
+
+ if (copy_from_user(&args, uarg, sizeof(args)))
+ return -EFAULT;
+
+ return ocxl_global_mmio_write64(scm_data->ocxl_afu, args.address,
+ OCXL_LITTLE_ENDIAN, args.val);
+}
+
+static int scm_ioctl_mmio_read(struct scm_data *scm_data,
+ struct scm_ioctl_mmio __user *uarg)
+{
+ struct scm_ioctl_mmio args;
+ int rc;
+
+ if (copy_from_user(&args, uarg, sizeof(args)))
+ return -EFAULT;
+
+ rc = ocxl_global_mmio_read64(scm_data->ocxl_afu, args.address,
+ OCXL_LITTLE_ENDIAN, &args.val);
+ if (rc)
+ return rc;
+
+ if (copy_to_user(uarg, &args, sizeof(args)))
+ return -EFAULT;
+
+ return 0;
+}
+#else /* CONFIG_OCXL_SCM_DEBUG */
+static int scm_ioctl_fwdebug(struct scm_data *scm_data,
+ struct scm_ioctl_fwdebug __user *uarg)
+{
+ return -EPERM;
+}
+
+static int scm_ioctl_shutdown(struct scm_data *scm_data)
+{
+ return -EPERM;
+}
+
+static int scm_ioctl_mmio_write(struct scm_data *scm_data,
+ struct scm_ioctl_mmio __user *uarg)
+{
+ return -EPERM;
+}
+
+static int scm_ioctl_mmio_read(struct scm_data *scm_data,
+ struct scm_ioctl_mmio __user *uarg)
+{
+ return -EPERM;
+}
+#endif /* CONFIG_OCXL_SCM_DEBUG */
+
static long scm_file_ioctl(struct file *file, unsigned int cmd,
unsigned long args)
{
@@ -1140,6 +1369,26 @@ static long scm_file_ioctl(struct file *file, unsigned int cmd,
case SCM_IOCTL_REQUEST_HEALTH:
rc = scm_req_controller_health_perf(scm_data);
break;
+
+ case SCM_IOCTL_FWDEBUG:
+ rc = scm_ioctl_fwdebug(scm_data,
+ (struct scm_ioctl_fwdebug __user *)args);
+ break;
+
+ case SCM_IOCTL_SHUTDOWN:
+ rc = scm_ioctl_shutdown(scm_data);
+ break;
+
+ case SCM_IOCTL_MMIO_WRITE:
+ rc = scm_ioctl_mmio_write(scm_data,
+ (struct scm_ioctl_mmio __user *)args);
+ break;
+
+ case SCM_IOCTL_MMIO_READ:
+ rc = scm_ioctl_mmio_read(scm_data,
+ (struct scm_ioctl_mmio __user *)args);
+ break;
+
}

return rc;
diff --git a/include/uapi/nvdimm/ocxl-scm.h b/include/uapi/nvdimm/ocxl-scm.h
index 55a7ad59d614..6e0f25c5f9f3 100644
--- a/include/uapi/nvdimm/ocxl-scm.h
+++ b/include/uapi/nvdimm/ocxl-scm.h
@@ -6,6 +6,28 @@
#include <linux/types.h>
#include <linux/ioctl.h>

+enum scm_fwdebug_action {
+ SCM_FWDEBUG_READ_CONTROLLER_MEMORY = 0x01,
+ SCM_FWDEBUG_WRITE_CONTROLLER_MEMORY = 0x02,
+ SCM_FWDEBUG_ENABLE_FUNCTION = 0x03,
+ SCM_FWDEBUG_DISABLE_FUNCTION = 0x04,
+ SCM_FWDEBUG_GET_PEL = 0x05, // Retrieve Persistent Error Log
+};
+
+struct scm_ioctl_buffer_info {
+ __u32 admin_command_buffer_size; // out
+ __u32 near_storage_buffer_size; // out
+};
+
+struct scm_ioctl_fwdebug { // All args are inputs
+ enum scm_fwdebug_action debug_action;
+ __u16 function_code;
+ __u16 buf_size; // Size of optional data buffer
+ __u64 debug_parameter_1;
+ __u64 debug_parameter_2;
+ __u8 *buf; // Pointer to optional in/out data buffer
+};
+
#define SCM_ERROR_LOG_ACTION_RESET (1 << (32-32))
#define SCM_ERROR_LOG_ACTION_CHKFW (1 << (53-32))
#define SCM_ERROR_LOG_ACTION_REPLACE (1 << (54-32))
@@ -66,6 +88,11 @@ struct scm_ioctl_controller_stats {
__u64 cache_write_latency; // nanoseconds
};

+struct scm_ioctl_mmio {
+ __u64 address; // Offset in global MMIO space
+ __u64 val; // value to write/was read
+};
+
struct scm_ioctl_eventfd {
__s32 eventfd;
__u32 reserved;
@@ -92,4 +119,9 @@ struct scm_ioctl_eventfd {
#define SCM_IOCTL_EVENT_CHECK _IOR(SCM_MAGIC, 0x07, __u64)
#define SCM_IOCTL_REQUEST_HEALTH _IO(SCM_MAGIC, 0x08)

+#define SCM_IOCTL_FWDEBUG _IOWR(SCM_MAGIC, 0xf0, struct scm_ioctl_fwdebug)
+#define SCM_IOCTL_MMIO_WRITE _IOW(SCM_MAGIC, 0xf1, struct scm_ioctl_mmio)
+#define SCM_IOCTL_MMIO_READ _IOWR(SCM_MAGIC, 0xf2, struct scm_ioctl_mmio)
+#define SCM_IOCTL_SHUTDOWN _IO(SCM_MAGIC, 0xf3)
+
#endif /* _UAPI_OCXL_SCM_H */
--
2.23.0