PCIEHP: Add Electro Mechanical Interlock (EMI) support to the PCIE hotplug driver.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 927dba9..d19fcae 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -69,6 +69,7 @@
struct hotplug_slot *hotplug_slot;
struct list_head slot_list;
char name[SLOT_NAME_SIZE];
+ unsigned long last_emi_toggle;
};
struct event_info {
@@ -138,6 +139,7 @@
#define ATTN_LED_PRSN 0x00000008
#define PWR_LED_PRSN 0x00000010
#define HP_SUPR_RM_SUP 0x00000020
+#define EMI_PRSN 0x00020000
#define ATTN_BUTTN(cap) (cap & ATTN_BUTTN_PRSN)
#define POWER_CTRL(cap) (cap & PWR_CTRL_PRSN)
@@ -145,6 +147,7 @@
#define ATTN_LED(cap) (cap & ATTN_LED_PRSN)
#define PWR_LED(cap) (cap & PWR_LED_PRSN)
#define HP_SUPR_RM(cap) (cap & HP_SUPR_RM_SUP)
+#define EMI(cap) (cap & EMI_PRSN)
extern int pciehp_event_start_thread(void);
extern void pciehp_event_stop_thread(void);
@@ -182,6 +185,8 @@
int (*set_attention_status)(struct slot *slot, u8 status);
int (*get_latch_status)(struct slot *slot, u8 *status);
int (*get_adapter_status)(struct slot *slot, u8 *status);
+ int (*get_emi_status)(struct slot *slot, u8 *status);
+ int (*toggle_emi)(struct slot *slot);
int (*get_max_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_cur_bus_speed)(struct slot *slot, enum pci_bus_speed *speed);
int (*get_max_lnk_width)(struct slot *slot, enum pcie_link_width *val);
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index f7b8e05..a92eda6 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -34,6 +34,7 @@
#include <linux/pci.h>
#include "pciehp.h"
#include <linux/interrupt.h>
+#include <linux/time.h>
/* Global variables */
int pciehp_debug;
@@ -87,6 +88,95 @@
.get_cur_bus_speed = get_cur_bus_speed,
};
+/*
+ * Check the status of the Electro Mechanical Interlock (EMI)
+ */
+static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
+{
+ struct slot *slot = hotplug_slot->private;
+ return (slot->hpc_ops->get_emi_status(slot, value));
+}
+
+/*
+ * sysfs interface for the Electro Mechanical Interlock (EMI)
+ * 1 == locked, 0 == unlocked
+ */
+static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
+{
+ int retval;
+ u8 value;
+
+ retval = get_lock_status(slot, &value);
+ if (retval)
+ goto lock_read_exit;
+ retval = sprintf (buf, "%d\n", value);
+
+lock_read_exit:
+ return retval;
+}
+
+/*
+ * Change the status of the Electro Mechanical Interlock (EMI)
+ * This is a toggle - in addition there must be at least 1 second
+ * in between toggles.
+ */
+static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
+{
+ struct slot *slot = hotplug_slot->private;
+ int retval;
+ u8 value;
+
+ mutex_lock(&slot->ctrl->crit_sect);
+
+ /* has it been >1 sec since our last toggle? */
+ if ((get_seconds() - slot->last_emi_toggle) < 1)
+ return -EINVAL;
+
+ /* see what our current state is */
+ retval = get_lock_status(hotplug_slot, &value);
+ if (retval || (value == status))
+ goto set_lock_exit;
+
+ slot->hpc_ops->toggle_emi(slot);
+set_lock_exit:
+ mutex_unlock(&slot->ctrl->crit_sect);
+ return 0;
+}
+
+/*
+ * sysfs interface which allows the user to toggle the Electro Mechanical
+ * Interlock. Valid values are either 0 or 1. 0 == unlock, 1 == lock
+ */
+static ssize_t lock_write_file(struct hotplug_slot *slot, const char *buf,
+ size_t count)
+{
+ unsigned long llock;
+ u8 lock;
+ int retval = 0;
+
+ llock = simple_strtoul(buf, NULL, 10);
+ lock = (u8)(llock & 0xff);
+
+ switch (lock) {
+ case 0:
+ case 1:
+ retval = set_lock_status(slot, lock);
+ break;
+ default:
+ err ("%d is an invalid lock value\n", lock);
+ retval = -EINVAL;
+ }
+ if (retval)
+ return retval;
+ return count;
+}
+
+static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
+ .attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
+ .show = lock_read_file,
+ .store = lock_write_file
+};
+
/**
* release_slot - free up the memory used by a slot
* @hotplug_slot: slot to free
@@ -159,6 +249,16 @@
err ("pci_hp_register failed with error %d\n", retval);
goto error_info;
}
+ /* create additional sysfs entries */
+ if (EMI(ctrl->ctrlcap)) {
+ retval = sysfs_create_file(&hotplug_slot->kobj,
+ &hotplug_slot_attr_lock.attr);
+ if (retval) {
+ pci_hp_deregister(hotplug_slot);
+ err("cannot create additional sysfs entries\n");
+ goto error_info;
+ }
+ }
list_add(&slot->slot_list, &ctrl->slot_list);
}
@@ -183,6 +283,9 @@
list_for_each_safe(tmp, next, &ctrl->slot_list) {
slot = list_entry(tmp, struct slot, slot_list);
list_del(&slot->slot_list);
+ if (EMI(ctrl->ctrlcap))
+ sysfs_remove_file(&slot->hotplug_slot->kobj,
+ &hotplug_slot_attr_lock.attr);
pci_hp_deregister(slot->hotplug_slot);
}
}
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index eb1862b..fbc64aa 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -35,6 +35,7 @@
#include <linux/timer.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
+#include <linux/time.h>
#include "../pci.h"
#include "pciehp.h"
@@ -192,6 +193,7 @@
#define ATTN_LED_CTRL 0x00C0
#define PWR_LED_CTRL 0x0300
#define PWR_CTRL 0x0400
+#define EMI_CTRL 0x0800
/* Attention indicator and Power indicator states */
#define LED_ON 0x01
@@ -202,6 +204,10 @@
#define POWER_ON 0
#define POWER_OFF 0x0400
+/* EMI Status defines */
+#define EMI_DISENGAGED 0
+#define EMI_ENGAGED 1
+
/* Field definitions in Slot Status Register */
#define ATTN_BUTTN_PRESSED 0x0001
#define PWR_FAULT_DETECTED 0x0002
@@ -210,6 +216,8 @@
#define CMD_COMPLETED 0x0010
#define MRL_STATE 0x0020
#define PRSN_STATE 0x0040
+#define EMI_STATE 0x0080
+#define EMI_STATUS_BIT 7
static spinlock_t hpc_event_lock;
@@ -474,6 +482,51 @@
return pwr_fault;
}
+static int hpc_get_emi_status(struct slot *slot, u8 *status)
+{
+ struct controller *ctrl = slot->ctrl;
+ u16 slot_status;
+ int retval = 0;
+
+ DBG_ENTER_ROUTINE
+
+ retval = pciehp_readw(ctrl, SLOTSTATUS, &slot_status);
+ if (retval) {
+ err("%s : Cannot check EMI status\n", __FUNCTION__);
+ return retval;
+ }
+ *status = (slot_status & EMI_STATE) >> EMI_STATUS_BIT;
+
+ DBG_LEAVE_ROUTINE
+ return retval;
+}
+
+static int hpc_toggle_emi(struct slot *slot)
+{
+ struct controller *ctrl = slot->ctrl;
+ u16 slot_cmd = 0;
+ u16 slot_ctrl;
+ int rc = 0;
+
+ DBG_ENTER_ROUTINE
+
+ rc = pciehp_readw(ctrl, SLOTCTRL, &slot_ctrl);
+ if (rc) {
+ err("%s : hp_register_read_word SLOT_CTRL failed\n",
+ __FUNCTION__);
+ return rc;
+ }
+
+ slot_cmd = (slot_ctrl | EMI_CTRL);
+ if (!pciehp_poll_mode)
+ slot_cmd = slot_cmd | HP_INTR_ENABLE;
+
+ pcie_write_cmd(slot, slot_cmd);
+ slot->last_emi_toggle = get_seconds();
+ DBG_LEAVE_ROUTINE
+ return rc;
+}
+
static int hpc_set_attention_status(struct slot *slot, u8 value)
{
struct controller *ctrl = slot->ctrl;
@@ -1009,6 +1062,8 @@
.get_attention_status = hpc_get_attention_status,
.get_latch_status = hpc_get_latch_status,
.get_adapter_status = hpc_get_adapter_status,
+ .get_emi_status = hpc_get_emi_status,
+ .toggle_emi = hpc_toggle_emi,
.get_max_bus_speed = hpc_get_max_lnk_speed,
.get_cur_bus_speed = hpc_get_cur_lnk_speed,