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platform/x86: ISST: Add Intel Speed Select PUNIT MSR interface

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While using new non arhitectural features using PUNIT Mailbox and MMIO
read/write interface, still there is need to operate using MSRs to
control PUNIT. User space could have used user user-space MSR interface for
this, but when user space MSR access is disabled, then it can't. Here only
limited number of MSRs are allowed using this new interface.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This commit is contained in:
Srinivas Pandruvada 2019-06-26 15:38:49 -07:00 committed by Andy Shevchenko
parent 71b21bd7f6
commit e765f37b9b
2 changed files with 91 additions and 0 deletions
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59
drivers/platform/x86/intel_speed_select_if/isst_if_common.c
View File

@ -25,6 +25,11 @@
static struct isst_if_cmd_cb punit_callbacks[ISST_IF_DEV_MAX];
static int punit_msr_white_list[] = {
MSR_TURBO_RATIO_LIMIT,
MSR_CONFIG_TDP_CONTROL,
};
struct isst_valid_cmd_ranges {
u16 cmd;
u16 sub_cmd_beg;
@ -229,6 +234,54 @@ static long isst_if_proc_phyid_req(u8 *cmd_ptr, int *write_only, int resume)
return 0;
}
static bool match_punit_msr_white_list(int msr)
{
int i;
for (i = 0; i < ARRAY_SIZE(punit_msr_white_list); ++i) {
if (punit_msr_white_list[i] == msr)
return true;
}
return false;
}
static long isst_if_msr_cmd_req(u8 *cmd_ptr, int *write_only, int resume)
{
struct isst_if_msr_cmd *msr_cmd;
int ret;
msr_cmd = (struct isst_if_msr_cmd *)cmd_ptr;
if (!match_punit_msr_white_list(msr_cmd->msr))
return -EINVAL;
if (msr_cmd->logical_cpu >= nr_cpu_ids)
return -EINVAL;
if (msr_cmd->read_write) {
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
ret = wrmsrl_safe_on_cpu(msr_cmd->logical_cpu,
msr_cmd->msr,
msr_cmd->data);
*write_only = 1;
} else {
u64 data;
ret = rdmsrl_safe_on_cpu(msr_cmd->logical_cpu,
msr_cmd->msr, &data);
if (!ret) {
msr_cmd->data = data;
*write_only = 0;
}
}
return ret;
}
static long isst_if_exec_multi_cmd(void __user *argp, struct isst_if_cmd_cb *cb)
{
unsigned char __user *ptr;
@ -309,6 +362,12 @@ static long isst_if_def_ioctl(struct file *file, unsigned int cmd,
if (cb->registered)
ret = isst_if_exec_multi_cmd(argp, cb);
break;
case ISST_IF_MSR_COMMAND:
cmd_cb.cmd_size = sizeof(struct isst_if_msr_cmd);
cmd_cb.offset = offsetof(struct isst_if_msr_cmds, msr_cmd);
cmd_cb.cmd_callback = isst_if_msr_cmd_req;
ret = isst_if_exec_multi_cmd(argp, &cmd_cb);
break;
default:
break;
}

32
include/uapi/linux/isst_if.h
View File

@ -132,9 +132,41 @@ struct isst_if_mbox_cmds {
struct isst_if_mbox_cmd mbox_cmd[1];
};
/**
* struct isst_if_msr_cmd - Structure to define msr command
* @read_write: Value 0: Read, 1: Write
* @logical_cpu: Logical CPU number
* @msr: MSR number
* @data: For write operation, data to write, for read
* place holder
*
* Structure to specify MSR command related to PUNIT.
*/
struct isst_if_msr_cmd {
__u32 read_write; /* Read:0, Write:1 */
__u32 logical_cpu;
__u64 msr;
__u64 data;
};
/**
* struct isst_if_msr_cmds - structure for msr commands
* @cmd_count: Number of mailbox commands in msr_cmd[]
* @msr_cmd[]: Holds one or more msr commands
*
* This structure used with ioctl ISST_IF_MSR_COMMAND to send
* one or more MSR commands. IOCTL return value indicates number of
* commands sent or error number if no commands have been sent.
*/
struct isst_if_msr_cmds {
__u32 cmd_count;
struct isst_if_msr_cmd msr_cmd[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 *)
#define ISST_IF_IO_CMD _IOW(ISST_IF_MAGIC, 2, struct isst_if_io_regs *)
#define ISST_IF_MBOX_COMMAND _IOWR(ISST_IF_MAGIC, 3, struct isst_if_mbox_cmds *)
#define ISST_IF_MSR_COMMAND _IOWR(ISST_IF_MAGIC, 4, struct isst_if_msr_cmds *)
#endif