[PATCH 04/10] platform/x86: ISST: Add IOCTL to Translate Linux logical CPU to PUNIT CPU number

From: Srinivas Pandruvada
Date: Wed Jun 26 2019 - 18:39:06 EST


Add processing for IOCTL command ISST_IF_GET_PHY_ID. This converts from the
Linux logical CPU to PUNIT CPU numbering scheme.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
.../intel_speed_select_if/isst_if_common.c | 74 +++++++++++++++++++
include/uapi/linux/isst_if.h | 28 +++++++
2 files changed, 102 insertions(+)

diff --git a/drivers/platform/x86/intel_speed_select_if/isst_if_common.c b/drivers/platform/x86/intel_speed_select_if/isst_if_common.c
index 0e16cbf685d0..72e74d72724b 100644
--- a/drivers/platform/x86/intel_speed_select_if/isst_if_common.c
+++ b/drivers/platform/x86/intel_speed_select_if/isst_if_common.c
@@ -134,16 +134,90 @@ static void isst_if_cpu_info_exit(void)
kfree(isst_cpu_info);
};

+static long isst_if_proc_phyid_req(u8 *cmd_ptr, int *write_only, int resume)
+{
+ struct isst_if_cpu_map *cpu_map;
+
+ cpu_map = (struct isst_if_cpu_map *)cmd_ptr;
+ if (cpu_map->logical_cpu >= nr_cpu_ids ||
+ cpu_map->logical_cpu >= num_possible_cpus())
+ return -EINVAL;
+
+ *write_only = 0;
+ cpu_map->physical_cpu = isst_cpu_info[cpu_map->logical_cpu].punit_cpu_id;
+
+ return 0;
+}
+
+static long isst_if_exec_multi_cmd(void __user *argp, struct isst_if_cmd_cb *cb)
+{
+ unsigned char __user *ptr;
+ u32 cmd_count;
+ u8 *cmd_ptr;
+ long ret;
+ int i;
+
+ /* Each multi command has u32 command count as the first field */
+ if (copy_from_user(&cmd_count, argp, sizeof(cmd_count)))
+ return -EFAULT;
+
+ if (!cmd_count || cmd_count > ISST_IF_CMD_LIMIT)
+ return -EINVAL;
+
+ cmd_ptr = kmalloc(cb->cmd_size, GFP_KERNEL);
+ if (!cmd_ptr)
+ return -ENOMEM;
+
+ /* cb->offset points to start of the command after the command count */
+ ptr = argp + cb->offset;
+
+ for (i = 0; i < cmd_count; ++i) {
+ int wr_only;
+
+ if (signal_pending(current)) {
+ ret = -EINTR;
+ break;
+ }
+
+ if (copy_from_user(cmd_ptr, ptr, cb->cmd_size)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ret = cb->cmd_callback(cmd_ptr, &wr_only, 0);
+ if (ret)
+ break;
+
+ if (!wr_only && copy_to_user(ptr, cmd_ptr, cb->cmd_size)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ptr += cb->cmd_size;
+ }
+
+ kfree(cmd_ptr);
+
+ return i ? i : ret;
+}
+
static long isst_if_def_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
+ struct isst_if_cmd_cb cmd_cb;
long ret = -ENOTTY;

switch (cmd) {
case ISST_IF_GET_PLATFORM_INFO:
ret = isst_if_get_platform_info(argp);
break;
+ case ISST_IF_GET_PHY_ID:
+ cmd_cb.cmd_size = sizeof(struct isst_if_cpu_map);
+ cmd_cb.offset = offsetof(struct isst_if_cpu_maps, cpu_map);
+ cmd_cb.cmd_callback = isst_if_proc_phyid_req;
+ ret = isst_if_exec_multi_cmd(argp, &cmd_cb);
+ break;
default:
break;
}
diff --git a/include/uapi/linux/isst_if.h b/include/uapi/linux/isst_if.h
index fa94480b5f74..15d1f286a830 100644
--- a/include/uapi/linux/isst_if.h
+++ b/include/uapi/linux/isst_if.h
@@ -36,6 +36,34 @@ struct isst_if_platform_info {
__u8 mmio_supported;
};

+/**
+ * struct isst_if_cpu_map - CPU mapping between logical and physical CPU
+ * @logical_cpu: Linux logical CPU number
+ * @physical_cpu: PUNIT CPU number
+ *
+ * Used to convert from Linux logical CPU to PUNIT CPU numbering scheme.
+ * The PUNIT CPU number is different than APIC ID based CPU numbering.
+ */
+struct isst_if_cpu_map {
+ __u32 logical_cpu;
+ __u32 physical_cpu;
+};
+
+/**
+ * struct isst_if_cpu_maps - structure for CPU map IOCTL
+ * @cmd_count: Number of CPU mapping command in cpu_map[]
+ * @cpu_map[]: Holds one or more CPU map data structure
+ *
+ * This structure used with ioctl ISST_IF_GET_PHY_ID to send
+ * one or more CPU mapping commands. Here IOCTL return value indicates
+ * number of commands sent or error number if no commands have been sent.
+ */
+struct isst_if_cpu_maps {
+ __u32 cmd_count;
+ struct isst_if_cpu_map cpu_map[1];
+};
+
#define ISST_IF_MAGIC 0xFE
#define ISST_IF_GET_PLATFORM_INFO _IOR(ISST_IF_MAGIC, 0, struct isst_if_platform_info *)
+#define ISST_IF_GET_PHY_ID _IOWR(ISST_IF_MAGIC, 1, struct isst_if_cpu_map *)
#endif
--
2.17.2