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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pci/hotplug/pciehp_ctrl.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/hotplug/pciehp_ctrl.c')
-rw-r--r-- | drivers/pci/hotplug/pciehp_ctrl.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c new file mode 100644 index 000000000..c71964e29 --- /dev/null +++ b/drivers/pci/hotplug/pciehp_ctrl.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * PCI Express Hot Plug Controller Driver + * + * Copyright (C) 1995,2001 Compaq Computer Corporation + * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) + * Copyright (C) 2001 IBM Corp. + * Copyright (C) 2003-2004 Intel Corporation + * + * All rights reserved. + * + * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com> + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/pci.h> +#include "../pci.h" +#include "pciehp.h" + +/* The following routines constitute the bulk of the + hotplug controller logic + */ + +static void set_slot_off(struct controller *ctrl, struct slot *pslot) +{ + /* turn off slot, turn on Amber LED, turn off Green LED if supported*/ + if (POWER_CTRL(ctrl)) { + pciehp_power_off_slot(pslot); + + /* + * After turning power off, we must wait for at least 1 second + * before taking any action that relies on power having been + * removed from the slot/adapter. + */ + msleep(1000); + } + + pciehp_green_led_off(pslot); + pciehp_set_attention_status(pslot, 1); +} + +/** + * board_added - Called after a board has been added to the system. + * @p_slot: &slot where board is added + * + * Turns power on for the board. + * Configures board. + */ +static int board_added(struct slot *p_slot) +{ + int retval = 0; + struct controller *ctrl = p_slot->ctrl; + struct pci_bus *parent = ctrl->pcie->port->subordinate; + + if (POWER_CTRL(ctrl)) { + /* Power on slot */ + retval = pciehp_power_on_slot(p_slot); + if (retval) + return retval; + } + + pciehp_green_led_blink(p_slot); + + /* Check link training status */ + retval = pciehp_check_link_status(ctrl); + if (retval) { + ctrl_err(ctrl, "Failed to check link status\n"); + goto err_exit; + } + + /* Check for a power fault */ + if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) { + ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(p_slot)); + retval = -EIO; + goto err_exit; + } + + retval = pciehp_configure_device(p_slot); + if (retval) { + if (retval != -EEXIST) { + ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n", + pci_domain_nr(parent), parent->number); + goto err_exit; + } + } + + pciehp_green_led_on(p_slot); + pciehp_set_attention_status(p_slot, 0); + return 0; + +err_exit: + set_slot_off(ctrl, p_slot); + return retval; +} + +/** + * remove_board - Turns off slot and LEDs + * @p_slot: slot where board is being removed + */ +static void remove_board(struct slot *p_slot) +{ + struct controller *ctrl = p_slot->ctrl; + + pciehp_unconfigure_device(p_slot); + + if (POWER_CTRL(ctrl)) { + pciehp_power_off_slot(p_slot); + + /* + * After turning power off, we must wait for at least 1 second + * before taking any action that relies on power having been + * removed from the slot/adapter. + */ + msleep(1000); + + /* Ignore link or presence changes caused by power off */ + atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC), + &ctrl->pending_events); + } + + /* turn off Green LED */ + pciehp_green_led_off(p_slot); +} + +static int pciehp_enable_slot(struct slot *slot); +static int pciehp_disable_slot(struct slot *slot); + +void pciehp_request(struct controller *ctrl, int action) +{ + atomic_or(action, &ctrl->pending_events); + if (!pciehp_poll_mode) + irq_wake_thread(ctrl->pcie->irq, ctrl); +} + +void pciehp_queue_pushbutton_work(struct work_struct *work) +{ + struct slot *p_slot = container_of(work, struct slot, work.work); + struct controller *ctrl = p_slot->ctrl; + + mutex_lock(&p_slot->lock); + switch (p_slot->state) { + case BLINKINGOFF_STATE: + pciehp_request(ctrl, DISABLE_SLOT); + break; + case BLINKINGON_STATE: + pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC); + break; + default: + break; + } + mutex_unlock(&p_slot->lock); +} + +void pciehp_handle_button_press(struct slot *p_slot) +{ + struct controller *ctrl = p_slot->ctrl; + + mutex_lock(&p_slot->lock); + switch (p_slot->state) { + case OFF_STATE: + case ON_STATE: + if (p_slot->state == ON_STATE) { + p_slot->state = BLINKINGOFF_STATE; + ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n", + slot_name(p_slot)); + } else { + p_slot->state = BLINKINGON_STATE; + ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n", + slot_name(p_slot)); + } + /* blink green LED and turn off amber */ + pciehp_green_led_blink(p_slot); + pciehp_set_attention_status(p_slot, 0); + schedule_delayed_work(&p_slot->work, 5 * HZ); + break; + case BLINKINGOFF_STATE: + case BLINKINGON_STATE: + /* + * Cancel if we are still blinking; this means that we + * press the attention again before the 5 sec. limit + * expires to cancel hot-add or hot-remove + */ + ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(p_slot)); + cancel_delayed_work(&p_slot->work); + if (p_slot->state == BLINKINGOFF_STATE) { + p_slot->state = ON_STATE; + pciehp_green_led_on(p_slot); + } else { + p_slot->state = OFF_STATE; + pciehp_green_led_off(p_slot); + } + pciehp_set_attention_status(p_slot, 0); + ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n", + slot_name(p_slot)); + break; + default: + ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n", + slot_name(p_slot), p_slot->state); + break; + } + mutex_unlock(&p_slot->lock); +} + +void pciehp_handle_disable_request(struct slot *slot) +{ + struct controller *ctrl = slot->ctrl; + + mutex_lock(&slot->lock); + switch (slot->state) { + case BLINKINGON_STATE: + case BLINKINGOFF_STATE: + cancel_delayed_work(&slot->work); + break; + } + slot->state = POWEROFF_STATE; + mutex_unlock(&slot->lock); + + ctrl->request_result = pciehp_disable_slot(slot); +} + +void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events) +{ + struct controller *ctrl = slot->ctrl; + bool link_active; + u8 present; + + /* + * If the slot is on and presence or link has changed, turn it off. + * Even if it's occupied again, we cannot assume the card is the same. + */ + mutex_lock(&slot->lock); + switch (slot->state) { + case BLINKINGOFF_STATE: + cancel_delayed_work(&slot->work); + /* fall through */ + case ON_STATE: + slot->state = POWEROFF_STATE; + mutex_unlock(&slot->lock); + if (events & PCI_EXP_SLTSTA_DLLSC) + ctrl_info(ctrl, "Slot(%s): Link Down\n", + slot_name(slot)); + if (events & PCI_EXP_SLTSTA_PDC) + ctrl_info(ctrl, "Slot(%s): Card not present\n", + slot_name(slot)); + pciehp_disable_slot(slot); + break; + default: + mutex_unlock(&slot->lock); + break; + } + + /* Turn the slot on if it's occupied or link is up */ + mutex_lock(&slot->lock); + pciehp_get_adapter_status(slot, &present); + link_active = pciehp_check_link_active(ctrl); + if (!present && !link_active) { + mutex_unlock(&slot->lock); + return; + } + + switch (slot->state) { + case BLINKINGON_STATE: + cancel_delayed_work(&slot->work); + /* fall through */ + case OFF_STATE: + slot->state = POWERON_STATE; + mutex_unlock(&slot->lock); + if (present) + ctrl_info(ctrl, "Slot(%s): Card present\n", + slot_name(slot)); + if (link_active) + ctrl_info(ctrl, "Slot(%s): Link Up\n", + slot_name(slot)); + ctrl->request_result = pciehp_enable_slot(slot); + break; + default: + mutex_unlock(&slot->lock); + break; + } +} + +static int __pciehp_enable_slot(struct slot *p_slot) +{ + u8 getstatus = 0; + struct controller *ctrl = p_slot->ctrl; + + pciehp_get_adapter_status(p_slot, &getstatus); + if (!getstatus) { + ctrl_info(ctrl, "Slot(%s): No adapter\n", slot_name(p_slot)); + return -ENODEV; + } + if (MRL_SENS(p_slot->ctrl)) { + pciehp_get_latch_status(p_slot, &getstatus); + if (getstatus) { + ctrl_info(ctrl, "Slot(%s): Latch open\n", + slot_name(p_slot)); + return -ENODEV; + } + } + + if (POWER_CTRL(p_slot->ctrl)) { + pciehp_get_power_status(p_slot, &getstatus); + if (getstatus) { + ctrl_info(ctrl, "Slot(%s): Already enabled\n", + slot_name(p_slot)); + return 0; + } + } + + return board_added(p_slot); +} + +static int pciehp_enable_slot(struct slot *slot) +{ + struct controller *ctrl = slot->ctrl; + int ret; + + pm_runtime_get_sync(&ctrl->pcie->port->dev); + ret = __pciehp_enable_slot(slot); + if (ret && ATTN_BUTTN(ctrl)) + pciehp_green_led_off(slot); /* may be blinking */ + pm_runtime_put(&ctrl->pcie->port->dev); + + mutex_lock(&slot->lock); + slot->state = ret ? OFF_STATE : ON_STATE; + mutex_unlock(&slot->lock); + + return ret; +} + +static int __pciehp_disable_slot(struct slot *p_slot) +{ + u8 getstatus = 0; + struct controller *ctrl = p_slot->ctrl; + + if (POWER_CTRL(p_slot->ctrl)) { + pciehp_get_power_status(p_slot, &getstatus); + if (!getstatus) { + ctrl_info(ctrl, "Slot(%s): Already disabled\n", + slot_name(p_slot)); + return -EINVAL; + } + } + + remove_board(p_slot); + return 0; +} + +static int pciehp_disable_slot(struct slot *slot) +{ + struct controller *ctrl = slot->ctrl; + int ret; + + pm_runtime_get_sync(&ctrl->pcie->port->dev); + ret = __pciehp_disable_slot(slot); + pm_runtime_put(&ctrl->pcie->port->dev); + + mutex_lock(&slot->lock); + slot->state = OFF_STATE; + mutex_unlock(&slot->lock); + + return ret; +} + +int pciehp_sysfs_enable_slot(struct slot *p_slot) +{ + struct controller *ctrl = p_slot->ctrl; + + mutex_lock(&p_slot->lock); + switch (p_slot->state) { + case BLINKINGON_STATE: + case OFF_STATE: + mutex_unlock(&p_slot->lock); + /* + * The IRQ thread becomes a no-op if the user pulls out the + * card before the thread wakes up, so initialize to -ENODEV. + */ + ctrl->request_result = -ENODEV; + pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC); + wait_event(ctrl->requester, + !atomic_read(&ctrl->pending_events) && + !ctrl->ist_running); + return ctrl->request_result; + case POWERON_STATE: + ctrl_info(ctrl, "Slot(%s): Already in powering on state\n", + slot_name(p_slot)); + break; + case BLINKINGOFF_STATE: + case ON_STATE: + case POWEROFF_STATE: + ctrl_info(ctrl, "Slot(%s): Already enabled\n", + slot_name(p_slot)); + break; + default: + ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n", + slot_name(p_slot), p_slot->state); + break; + } + mutex_unlock(&p_slot->lock); + + return -ENODEV; +} + +int pciehp_sysfs_disable_slot(struct slot *p_slot) +{ + struct controller *ctrl = p_slot->ctrl; + + mutex_lock(&p_slot->lock); + switch (p_slot->state) { + case BLINKINGOFF_STATE: + case ON_STATE: + mutex_unlock(&p_slot->lock); + pciehp_request(ctrl, DISABLE_SLOT); + wait_event(ctrl->requester, + !atomic_read(&ctrl->pending_events) && + !ctrl->ist_running); + return ctrl->request_result; + case POWEROFF_STATE: + ctrl_info(ctrl, "Slot(%s): Already in powering off state\n", + slot_name(p_slot)); + break; + case BLINKINGON_STATE: + case OFF_STATE: + case POWERON_STATE: + ctrl_info(ctrl, "Slot(%s): Already disabled\n", + slot_name(p_slot)); + break; + default: + ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n", + slot_name(p_slot), p_slot->state); + break; + } + mutex_unlock(&p_slot->lock); + + return -ENODEV; +} |