diff options
Diffstat (limited to 'drivers/pci/pcie/aspm.c')
| -rw-r--r-- | drivers/pci/pcie/aspm.c | 1044 |
1 files changed, 589 insertions, 455 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 9a7c9e1408a..e1e7026b838 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1,6 +1,6 @@ /* * File: drivers/pci/pcie/aspm.c - * Enabling PCIE link L0s/L1 state and Clock Power Management + * Enabling PCIe link L0s/L1 state and Clock Power Management * * Copyright (C) 2007 Intel * Copyright (C) Zhang Yanmin (yanmin.zhang@intel.com) @@ -16,6 +16,8 @@ #include <linux/pm.h> #include <linux/init.h> #include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/delay.h> #include <linux/pci-aspm.h> #include "../pci.h" @@ -24,72 +26,90 @@ #endif #define MODULE_PARAM_PREFIX "pcie_aspm." -struct endpoint_state { - unsigned int l0s_acceptable_latency; - unsigned int l1_acceptable_latency; +/* Note: those are not register definitions */ +#define ASPM_STATE_L0S_UP (1) /* Upstream direction L0s state */ +#define ASPM_STATE_L0S_DW (2) /* Downstream direction L0s state */ +#define ASPM_STATE_L1 (4) /* L1 state */ +#define ASPM_STATE_L0S (ASPM_STATE_L0S_UP | ASPM_STATE_L0S_DW) +#define ASPM_STATE_ALL (ASPM_STATE_L0S | ASPM_STATE_L1) + +struct aspm_latency { + u32 l0s; /* L0s latency (nsec) */ + u32 l1; /* L1 latency (nsec) */ }; struct pcie_link_state { - struct list_head sibiling; - struct pci_dev *pdev; + struct pci_dev *pdev; /* Upstream component of the Link */ + struct pcie_link_state *root; /* pointer to the root port link */ + struct pcie_link_state *parent; /* pointer to the parent Link state */ + struct list_head sibling; /* node in link_list */ + struct list_head children; /* list of child link states */ + struct list_head link; /* node in parent's children list */ /* ASPM state */ - unsigned int support_state; - unsigned int enabled_state; - unsigned int bios_aspm_state; - /* upstream component */ - unsigned int l0s_upper_latency; - unsigned int l1_upper_latency; - /* downstream component */ - unsigned int l0s_down_latency; - unsigned int l1_down_latency; - /* Clock PM state*/ - unsigned int clk_pm_capable; - unsigned int clk_pm_enabled; - unsigned int bios_clk_state; - + u32 aspm_support:3; /* Supported ASPM state */ + u32 aspm_enabled:3; /* Enabled ASPM state */ + u32 aspm_capable:3; /* Capable ASPM state with latency */ + u32 aspm_default:3; /* Default ASPM state by BIOS */ + u32 aspm_disable:3; /* Disabled ASPM state */ + + /* Clock PM state */ + u32 clkpm_capable:1; /* Clock PM capable? */ + u32 clkpm_enabled:1; /* Current Clock PM state */ + u32 clkpm_default:1; /* Default Clock PM state by BIOS */ + + /* Exit latencies */ + struct aspm_latency latency_up; /* Upstream direction exit latency */ + struct aspm_latency latency_dw; /* Downstream direction exit latency */ /* - * A pcie downstream port only has one slot under it, so at most there - * are 8 functions + * Endpoint acceptable latencies. A pcie downstream port only + * has one slot under it, so at most there are 8 functions. */ - struct endpoint_state endpoints[8]; + struct aspm_latency acceptable[8]; }; static int aspm_disabled, aspm_force; +static bool aspm_support_enabled = true; static DEFINE_MUTEX(aspm_lock); static LIST_HEAD(link_list); #define POLICY_DEFAULT 0 /* BIOS default setting */ #define POLICY_PERFORMANCE 1 /* high performance */ #define POLICY_POWERSAVE 2 /* high power saving */ + +#ifdef CONFIG_PCIEASPM_PERFORMANCE +static int aspm_policy = POLICY_PERFORMANCE; +#elif defined CONFIG_PCIEASPM_POWERSAVE +static int aspm_policy = POLICY_POWERSAVE; +#else static int aspm_policy; +#endif + static const char *policy_str[] = { [POLICY_DEFAULT] = "default", [POLICY_PERFORMANCE] = "performance", [POLICY_POWERSAVE] = "powersave" }; -static int policy_to_aspm_state(struct pci_dev *pdev) -{ - struct pcie_link_state *link_state = pdev->link_state; +#define LINK_RETRAIN_TIMEOUT HZ +static int policy_to_aspm_state(struct pcie_link_state *link) +{ switch (aspm_policy) { case POLICY_PERFORMANCE: /* Disable ASPM and Clock PM */ return 0; case POLICY_POWERSAVE: /* Enable ASPM L0s/L1 */ - return PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1; + return ASPM_STATE_ALL; case POLICY_DEFAULT: - return link_state->bios_aspm_state; + return link->aspm_default; } return 0; } -static int policy_to_clkpm_state(struct pci_dev *pdev) +static int policy_to_clkpm_state(struct pcie_link_state *link) { - struct pcie_link_state *link_state = pdev->link_state; - switch (aspm_policy) { case POLICY_PERFORMANCE: /* Disable ASPM and Clock PM */ @@ -98,60 +118,61 @@ static int policy_to_clkpm_state(struct pci_dev *pdev) /* Disable Clock PM */ return 1; case POLICY_DEFAULT: - return link_state->bios_clk_state; + return link->clkpm_default; } return 0; } -static void pcie_set_clock_pm(struct pci_dev *pdev, int enable) +static void pcie_set_clkpm_nocheck(struct pcie_link_state *link, int enable) { - struct pci_dev *child_dev; - int pos; - u16 reg16; - struct pcie_link_state *link_state = pdev->link_state; + struct pci_dev *child; + struct pci_bus *linkbus = link->pdev->subordinate; - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - if (!pos) - return; - pci_read_config_word(child_dev, pos + PCI_EXP_LNKCTL, ®16); + list_for_each_entry(child, &linkbus->devices, bus_list) { if (enable) - reg16 |= PCI_EXP_LNKCTL_CLKREQ_EN; + pcie_capability_set_word(child, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_CLKREQ_EN); else - reg16 &= ~PCI_EXP_LNKCTL_CLKREQ_EN; - pci_write_config_word(child_dev, pos + PCI_EXP_LNKCTL, reg16); + pcie_capability_clear_word(child, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_CLKREQ_EN); } - link_state->clk_pm_enabled = !!enable; + link->clkpm_enabled = !!enable; } -static void pcie_check_clock_pm(struct pci_dev *pdev) +static void pcie_set_clkpm(struct pcie_link_state *link, int enable) { - int pos; + /* Don't enable Clock PM if the link is not Clock PM capable */ + if (!link->clkpm_capable && enable) + enable = 0; + /* Need nothing if the specified equals to current state */ + if (link->clkpm_enabled == enable) + return; + pcie_set_clkpm_nocheck(link, enable); +} + +static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist) +{ + int capable = 1, enabled = 1; u32 reg32; u16 reg16; - int capable = 1, enabled = 1; - struct pci_dev *child_dev; - struct pcie_link_state *link_state = pdev->link_state; + struct pci_dev *child; + struct pci_bus *linkbus = link->pdev->subordinate; /* All functions should have the same cap and state, take the worst */ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - if (!pos) - return; - pci_read_config_dword(child_dev, pos + PCI_EXP_LNKCAP, ®32); + list_for_each_entry(child, &linkbus->devices, bus_list) { + pcie_capability_read_dword(child, PCI_EXP_LNKCAP, ®32); if (!(reg32 & PCI_EXP_LNKCAP_CLKPM)) { capable = 0; enabled = 0; break; } - pci_read_config_word(child_dev, pos + PCI_EXP_LNKCTL, ®16); + pcie_capability_read_word(child, PCI_EXP_LNKCTL, ®16); if (!(reg16 & PCI_EXP_LNKCTL_CLKREQ_EN)) enabled = 0; } - link_state->clk_pm_capable = capable; - link_state->clk_pm_enabled = enabled; - link_state->bios_clk_state = enabled; - pcie_set_clock_pm(pdev, policy_to_clkpm_state(pdev)); + link->clkpm_enabled = enabled; + link->clkpm_default = enabled; + link->clkpm_capable = (blacklist) ? 0 : capable; } /* @@ -159,462 +180,491 @@ static void pcie_check_clock_pm(struct pci_dev *pdev) * could use common clock. If they are, configure them to use the * common clock. That will reduce the ASPM state exit latency. */ -static void pcie_aspm_configure_common_clock(struct pci_dev *pdev) +static void pcie_aspm_configure_common_clock(struct pcie_link_state *link) { - int pos, child_pos; - u16 reg16 = 0; - struct pci_dev *child_dev; int same_clock = 1; - + u16 reg16, parent_reg, child_reg[8]; + unsigned long start_jiffies; + struct pci_dev *child, *parent = link->pdev; + struct pci_bus *linkbus = parent->subordinate; /* - * all functions of a slot should have the same Slot Clock + * All functions of a slot should have the same Slot Clock * Configuration, so just check one function - * */ - child_dev = list_entry(pdev->subordinate->devices.next, struct pci_dev, - bus_list); - BUG_ON(!child_dev->is_pcie); + */ + child = list_entry(linkbus->devices.next, struct pci_dev, bus_list); + BUG_ON(!pci_is_pcie(child)); /* Check downstream component if bit Slot Clock Configuration is 1 */ - child_pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - pci_read_config_word(child_dev, child_pos + PCI_EXP_LNKSTA, ®16); + pcie_capability_read_word(child, PCI_EXP_LNKSTA, ®16); if (!(reg16 & PCI_EXP_LNKSTA_SLC)) same_clock = 0; /* Check upstream component if bit Slot Clock Configuration is 1 */ - pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); - pci_read_config_word(pdev, pos + PCI_EXP_LNKSTA, ®16); + pcie_capability_read_word(parent, PCI_EXP_LNKSTA, ®16); if (!(reg16 & PCI_EXP_LNKSTA_SLC)) same_clock = 0; /* Configure downstream component, all functions */ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - child_pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - pci_read_config_word(child_dev, child_pos + PCI_EXP_LNKCTL, - ®16); + list_for_each_entry(child, &linkbus->devices, bus_list) { + pcie_capability_read_word(child, PCI_EXP_LNKCTL, ®16); + child_reg[PCI_FUNC(child->devfn)] = reg16; if (same_clock) reg16 |= PCI_EXP_LNKCTL_CCC; else reg16 &= ~PCI_EXP_LNKCTL_CCC; - pci_write_config_word(child_dev, child_pos + PCI_EXP_LNKCTL, - reg16); + pcie_capability_write_word(child, PCI_EXP_LNKCTL, reg16); } /* Configure upstream component */ - pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); + pcie_capability_read_word(parent, PCI_EXP_LNKCTL, ®16); + parent_reg = reg16; if (same_clock) reg16 |= PCI_EXP_LNKCTL_CCC; else reg16 &= ~PCI_EXP_LNKCTL_CCC; - pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); - /* retrain link */ + /* Retrain link */ reg16 |= PCI_EXP_LNKCTL_RL; - pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); - /* Wait for link training end */ - while (1) { - pci_read_config_word(pdev, pos + PCI_EXP_LNKSTA, ®16); + /* Wait for link training end. Break out after waiting for timeout */ + start_jiffies = jiffies; + for (;;) { + pcie_capability_read_word(parent, PCI_EXP_LNKSTA, ®16); if (!(reg16 & PCI_EXP_LNKSTA_LT)) break; - cpu_relax(); + if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) + break; + msleep(1); } + if (!(reg16 & PCI_EXP_LNKSTA_LT)) + return; + + /* Training failed. Restore common clock configurations */ + dev_err(&parent->dev, "ASPM: Could not configure common clock\n"); + list_for_each_entry(child, &linkbus->devices, bus_list) + pcie_capability_write_word(child, PCI_EXP_LNKCTL, + child_reg[PCI_FUNC(child->devfn)]); + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, parent_reg); } -/* - * calc_L0S_latency: Convert L0s latency encoding to ns - */ -static unsigned int calc_L0S_latency(unsigned int latency_encoding, int ac) +/* Convert L0s latency encoding to ns */ +static u32 calc_l0s_latency(u32 encoding) { - unsigned int ns = 64; + if (encoding == 0x7) + return (5 * 1000); /* > 4us */ + return (64 << encoding); +} - if (latency_encoding == 0x7) { - if (ac) - ns = -1U; - else - ns = 5*1000; /* > 4us */ - } else - ns *= (1 << latency_encoding); - return ns; +/* Convert L0s acceptable latency encoding to ns */ +static u32 calc_l0s_acceptable(u32 encoding) +{ + if (encoding == 0x7) + return -1U; + return (64 << encoding); } -/* - * calc_L1_latency: Convert L1 latency encoding to ns - */ -static unsigned int calc_L1_latency(unsigned int latency_encoding, int ac) +/* Convert L1 latency encoding to ns */ +static u32 calc_l1_latency(u32 encoding) { - unsigned int ns = 1000; + if (encoding == 0x7) + return (65 * 1000); /* > 64us */ + return (1000 << encoding); +} - if (latency_encoding == 0x7) { - if (ac) - ns = -1U; - else - ns = 65*1000; /* > 64us */ - } else - ns *= (1 << latency_encoding); - return ns; +/* Convert L1 acceptable latency encoding to ns */ +static u32 calc_l1_acceptable(u32 encoding) +{ + if (encoding == 0x7) + return -1U; + return (1000 << encoding); } -static void pcie_aspm_get_cap_device(struct pci_dev *pdev, u32 *state, - unsigned int *l0s, unsigned int *l1, unsigned int *enabled) +struct aspm_register_info { + u32 support:2; + u32 enabled:2; + u32 latency_encoding_l0s; + u32 latency_encoding_l1; +}; + +static void pcie_get_aspm_reg(struct pci_dev *pdev, + struct aspm_register_info *info) { - int pos; u16 reg16; u32 reg32; - unsigned int latency; - - pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); - pci_read_config_dword(pdev, pos + PCI_EXP_LNKCAP, ®32); - *state = (reg32 & PCI_EXP_LNKCAP_ASPMS) >> 10; - if (*state != PCIE_LINK_STATE_L0S && - *state != (PCIE_LINK_STATE_L1|PCIE_LINK_STATE_L0S)) - *state = 0; - if (*state == 0) - return; - latency = (reg32 & PCI_EXP_LNKCAP_L0SEL) >> 12; - *l0s = calc_L0S_latency(latency, 0); - if (*state & PCIE_LINK_STATE_L1) { - latency = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15; - *l1 = calc_L1_latency(latency, 0); - } - pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); - *enabled = reg16 & (PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1); + pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, ®32); + info->support = (reg32 & PCI_EXP_LNKCAP_ASPMS) >> 10; + info->latency_encoding_l0s = (reg32 & PCI_EXP_LNKCAP_L0SEL) >> 12; + info->latency_encoding_l1 = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15; + pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, ®16); + info->enabled = reg16 & PCI_EXP_LNKCTL_ASPMC; } -static void pcie_aspm_cap_init(struct pci_dev *pdev) +static void pcie_aspm_check_latency(struct pci_dev *endpoint) { - struct pci_dev *child_dev; - u32 state, tmp; - struct pcie_link_state *link_state = pdev->link_state; + u32 latency, l1_switch_latency = 0; + struct aspm_latency *acceptable; + struct pcie_link_state *link; - /* upstream component states */ - pcie_aspm_get_cap_device(pdev, &link_state->support_state, - &link_state->l0s_upper_latency, - &link_state->l1_upper_latency, - &link_state->enabled_state); - /* downstream component states, all functions have the same setting */ - child_dev = list_entry(pdev->subordinate->devices.next, struct pci_dev, - bus_list); - pcie_aspm_get_cap_device(child_dev, &state, - &link_state->l0s_down_latency, - &link_state->l1_down_latency, - &tmp); - link_state->support_state &= state; - if (!link_state->support_state) + /* Device not in D0 doesn't need latency check */ + if ((endpoint->current_state != PCI_D0) && + (endpoint->current_state != PCI_UNKNOWN)) return; - link_state->enabled_state &= link_state->support_state; - link_state->bios_aspm_state = link_state->enabled_state; - - /* ENDPOINT states*/ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - int pos; - u32 reg32; - unsigned int latency; - struct endpoint_state *ep_state = - &link_state->endpoints[PCI_FUNC(child_dev->devfn)]; - - if (child_dev->pcie_type != PCI_EXP_TYPE_ENDPOINT && - child_dev->pcie_type != PCI_EXP_TYPE_LEG_END) - continue; - pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - pci_read_config_dword(child_dev, pos + PCI_EXP_DEVCAP, ®32); - latency = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6; - latency = calc_L0S_latency(latency, 1); - ep_state->l0s_acceptable_latency = latency; - if (link_state->support_state & PCIE_LINK_STATE_L1) { - latency = (reg32 & PCI_EXP_DEVCAP_L1) >> 9; - latency = calc_L1_latency(latency, 1); - ep_state->l1_acceptable_latency = latency; - } - } -} + link = endpoint->bus->self->link_state; + acceptable = &link->acceptable[PCI_FUNC(endpoint->devfn)]; -static unsigned int __pcie_aspm_check_state_one(struct pci_dev *pdev, - unsigned int state) -{ - struct pci_dev *parent_dev, *tmp_dev; - unsigned int latency, l1_latency = 0; - struct pcie_link_state *link_state; - struct endpoint_state *ep_state; + while (link) { + /* Check upstream direction L0s latency */ + if ((link->aspm_capable & ASPM_STATE_L0S_UP) && + (link->latency_up.l0s > acceptable->l0s)) + link->aspm_capable &= ~ASPM_STATE_L0S_UP; - parent_dev = pdev->bus->self; - link_state = parent_dev->link_state; - state &= link_state->support_state; - if (state == 0) - return 0; - ep_state = &link_state->endpoints[PCI_FUNC(pdev->devfn)]; + /* Check downstream direction L0s latency */ + if ((link->aspm_capable & ASPM_STATE_L0S_DW) && + (link->latency_dw.l0s > acceptable->l0s)) + link->aspm_capable &= ~ASPM_STATE_L0S_DW; + /* + * Check L1 latency. + * Every switch on the path to root complex need 1 + * more microsecond for L1. Spec doesn't mention L0s. + */ + latency = max_t(u32, link->latency_up.l1, link->latency_dw.l1); + if ((link->aspm_capable & ASPM_STATE_L1) && + (latency + l1_switch_latency > acceptable->l1)) + link->aspm_capable &= ~ASPM_STATE_L1; + l1_switch_latency += 1000; - /* - * Check latency for endpoint device. - * TBD: The latency from the endpoint to root complex vary per - * switch's upstream link state above the device. Here we just do a - * simple check which assumes all links above the device can be in L1 - * state, that is we just consider the worst case. If switch's upstream - * link can't be put into L0S/L1, then our check is too strictly. - */ - tmp_dev = pdev; - while (state & (PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1)) { - parent_dev = tmp_dev->bus->self; - link_state = parent_dev->link_state; - if (state & PCIE_LINK_STATE_L0S) { - latency = max_t(unsigned int, - link_state->l0s_upper_latency, - link_state->l0s_down_latency); - if (latency > ep_state->l0s_acceptable_latency) - state &= ~PCIE_LINK_STATE_L0S; - } - if (state & PCIE_LINK_STATE_L1) { - latency = max_t(unsigned int, - link_state->l1_upper_latency, - link_state->l1_down_latency); - if (latency + l1_latency > - ep_state->l1_acceptable_latency) - state &= ~PCIE_LINK_STATE_L1; - } - if (!parent_dev->bus->self) /* parent_dev is a root port */ - break; - else { - /* - * parent_dev is the downstream port of a switch, make - * tmp_dev the upstream port of the switch - */ - tmp_dev = parent_dev->bus->self; - /* - * every switch on the path to root complex need 1 more - * microsecond for L1. Spec doesn't mention L0S. - */ - if (state & PCIE_LINK_STATE_L1) - l1_latency += 1000; - } + link = link->parent; } - return state; } -static unsigned int pcie_aspm_check_state(struct pci_dev *pdev, - unsigned int state) +static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) { - struct pci_dev *child_dev; + struct pci_dev *child, *parent = link->pdev; + struct pci_bus *linkbus = parent->subordinate; + struct aspm_register_info upreg, dwreg; - /* If no child, disable the link */ - if (list_empty(&pdev->subordinate->devices)) - return 0; - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - if (child_dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) { - /* - * If downstream component of a link is pci bridge, we - * disable ASPM for now for the link - * */ - state = 0; - break; - } - if ((child_dev->pcie_type != PCI_EXP_TYPE_ENDPOINT && - child_dev->pcie_type != PCI_EXP_TYPE_LEG_END)) - continue; - /* Device not in D0 doesn't need check latency */ - if (child_dev->current_state == PCI_D1 || - child_dev->current_state == PCI_D2 || - child_dev->current_state == PCI_D3hot || - child_dev->current_state == PCI_D3cold) - continue; - state = __pcie_aspm_check_state_one(child_dev, state); + if (blacklist) { + /* Set enabled/disable so that we will disable ASPM later */ + link->aspm_enabled = ASPM_STATE_ALL; + link->aspm_disable = ASPM_STATE_ALL; + return; } - return state; -} -static void __pcie_aspm_config_one_dev(struct pci_dev *pdev, unsigned int state) -{ - u16 reg16; - int pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); + /* Configure common clock before checking latencies */ + pcie_aspm_configure_common_clock(link); - pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); - reg16 &= ~0x3; - reg16 |= state; - pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); -} - -static void __pcie_aspm_config_link(struct pci_dev *pdev, unsigned int state) -{ - struct pci_dev *child_dev; - int valid = 1; - struct pcie_link_state *link_state = pdev->link_state; + /* Get upstream/downstream components' register state */ + pcie_get_aspm_reg(parent, &upreg); + child = list_entry(linkbus->devices.next, struct pci_dev, bus_list); + pcie_get_aspm_reg(child, &dwreg); /* - * if the downstream component has pci bridge function, don't do ASPM - * now + * Setup L0s state + * + * Note that we must not enable L0s in either direction on a + * given link unless components on both sides of the link each + * support L0s. */ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - if (child_dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) { - valid = 0; + if (dwreg.support & upreg.support & PCIE_LINK_STATE_L0S) + link->aspm_support |= ASPM_STATE_L0S; + if (dwreg.enabled & PCIE_LINK_STATE_L0S) + link->aspm_enabled |= ASPM_STATE_L0S_UP; + if (upreg.enabled & PCIE_LINK_STATE_L0S) + link->aspm_enabled |= ASPM_STATE_L0S_DW; + link->latency_up.l0s = calc_l0s_latency(upreg.latency_encoding_l0s); + link->latency_dw.l0s = calc_l0s_latency(dwreg.latency_encoding_l0s); + + /* Setup L1 state */ + if (upreg.support & dwreg.support & PCIE_LINK_STATE_L1) + link->aspm_support |= ASPM_STATE_L1; + if (upreg.enabled & dwreg.enabled & PCIE_LINK_STATE_L1) + link->aspm_enabled |= ASPM_STATE_L1; + link->latency_up.l1 = calc_l1_latency(upreg.latency_encoding_l1); + link->latency_dw.l1 = calc_l1_latency(dwreg.latency_encoding_l1); + + /* Save default state */ + link->aspm_default = link->aspm_enabled; + + /* Setup initial capable state. Will be updated later */ + link->aspm_capable = link->aspm_support; + /* + * If the downstream component has pci bridge function, don't + * do ASPM for now. + */ + list_for_each_entry(child, &linkbus->devices, bus_list) { + if (pci_pcie_type(child) == PCI_EXP_TYPE_PCI_BRIDGE) { + link->aspm_disable = ASPM_STATE_ALL; break; } } - if (!valid) - return; - /* - * spec 2.0 suggests all functions should be configured the same - * setting for ASPM. Enabling ASPM L1 should be done in upstream - * component first and then downstream, and vice versa for disabling - * ASPM L1. Spec doesn't mention L0S. - */ - if (state & PCIE_LINK_STATE_L1) - __pcie_aspm_config_one_dev(pdev, state); + /* Get and check endpoint acceptable latencies */ + list_for_each_entry(child, &linkbus->devices, bus_list) { + u32 reg32, encoding; + struct aspm_latency *acceptable = + &link->acceptable[PCI_FUNC(child->devfn)]; - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) - __pcie_aspm_config_one_dev(child_dev, state); + if (pci_pcie_type(child) != PCI_EXP_TYPE_ENDPOINT && + pci_pcie_type(child) != PCI_EXP_TYPE_LEG_END) + continue; - if (!(state & PCIE_LINK_STATE_L1)) - __pcie_aspm_config_one_dev(pdev, state); + pcie_capability_read_dword(child, PCI_EXP_DEVCAP, ®32); + /* Calculate endpoint L0s acceptable latency */ + encoding = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6; + acceptable->l0s = calc_l0s_acceptable(encoding); + /* Calculate endpoint L1 acceptable latency */ + encoding = (reg32 & PCI_EXP_DEVCAP_L1) >> 9; + acceptable->l1 = calc_l1_acceptable(encoding); - link_state->enabled_state = state; + pcie_aspm_check_latency(child); + } } -static void __pcie_aspm_configure_link_state(struct pci_dev *pdev, - unsigned int state) +static void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val) { - struct pcie_link_state *link_state = pdev->link_state; + pcie_capability_clear_and_set_word(pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC, val); +} - if (link_state->support_state == 0) - return; - state &= PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1; +static void pcie_config_aspm_link(struct pcie_link_state *link, u32 state) +{ + u32 upstream = 0, dwstream = 0; + struct pci_dev *child, *parent = link->pdev; + struct pci_bus *linkbus = parent->subordinate; - /* state 0 means disabling aspm */ - state = pcie_aspm_check_state(pdev, state); - if (link_state->enabled_state == state) + /* Nothing to do if the link is already in the requested state */ + state &= (link->aspm_capable & ~link->aspm_disable); + if (link->aspm_enabled == state) return; - __pcie_aspm_config_link(pdev, state); + /* Convert ASPM state to upstream/downstream ASPM register state */ + if (state & ASPM_STATE_L0S_UP) + dwstream |= PCI_EXP_LNKCTL_ASPM_L0S; + if (state & ASPM_STATE_L0S_DW) + upstream |= PCI_EXP_LNKCTL_ASPM_L0S; + if (state & ASPM_STATE_L1) { + upstream |= PCI_EXP_LNKCTL_ASPM_L1; + dwstream |= PCI_EXP_LNKCTL_ASPM_L1; + } + /* + * Spec 2.0 suggests all functions should be configured the + * same setting for ASPM. Enabling ASPM L1 should be done in + * upstream component first and then downstream, and vice + * versa for disabling ASPM L1. Spec doesn't mention L0S. + */ + if (state & ASPM_STATE_L1) + pcie_config_aspm_dev(parent, upstream); + list_for_each_entry(child, &linkbus->devices, bus_list) + pcie_config_aspm_dev(child, dwstream); + if (!(state & ASPM_STATE_L1)) + pcie_config_aspm_dev(parent, upstream); + + link->aspm_enabled = state; } -/* - * pcie_aspm_configure_link_state: enable/disable PCI express link state - * @pdev: the root port or switch downstream port - */ -static void pcie_aspm_configure_link_state(struct pci_dev *pdev, - unsigned int state) +static void pcie_config_aspm_path(struct pcie_link_state *link) { - down_read(&pci_bus_sem); - mutex_lock(&aspm_lock); - __pcie_aspm_configure_link_state(pdev, state); - mutex_unlock(&aspm_lock); - up_read(&pci_bus_sem); + while (link) { + pcie_config_aspm_link(link, policy_to_aspm_state(link)); + link = link->parent; + } } -static void free_link_state(struct pci_dev *pdev) +static void free_link_state(struct pcie_link_state *link) { - kfree(pdev->link_state); - pdev->link_state = NULL; + link->pdev->link_state = NULL; + kfree(link); } static int pcie_aspm_sanity_check(struct pci_dev *pdev) { - struct pci_dev *child_dev; - int child_pos; + struct pci_dev *child; u32 reg32; /* - * Some functions in a slot might not all be PCIE functions, very - * strange. Disable ASPM for the whole slot + * Some functions in a slot might not all be PCIe functions, + * very strange. Disable ASPM for the whole slot */ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - child_pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP); - if (!child_pos) + list_for_each_entry(child, &pdev->subordinate->devices, bus_list) { + if (!pci_is_pcie(child)) return -EINVAL; /* + * If ASPM is disabled then we're not going to change + * the BIOS state. It's safe to continue even if it's a + * pre-1.1 device + */ + + if (aspm_disabled) + continue; + + /* * Disable ASPM for pre-1.1 PCIe device, we follow MS to use * RBER bit to determine if a function is 1.1 version device */ - pci_read_config_dword(child_dev, child_pos + PCI_EXP_DEVCAP, - ®32); - if (!(reg32 & PCI_EXP_DEVCAP_RBER && !aspm_force)) { - printk("Pre-1.1 PCIe device detected, " - "disable ASPM for %s. It can be enabled forcedly" - " with 'pcie_aspm=force'\n", pci_name(pdev)); + pcie_capability_read_dword(child, PCI_EXP_DEVCAP, ®32); + if (!(reg32 & PCI_EXP_DEVCAP_RBER) && !aspm_force) { + dev_info(&child->dev, "disabling ASPM on pre-1.1 PCIe device. You can enable it with 'pcie_aspm=force'\n"); return -EINVAL; } } return 0; } +static struct pcie_link_state *alloc_pcie_link_state(struct pci_dev *pdev) +{ + struct pcie_link_state *link; + + link = kzalloc(sizeof(*link), GFP_KERNEL); + if (!link) + return NULL; + INIT_LIST_HEAD(&link->sibling); + INIT_LIST_HEAD(&link->children); + INIT_LIST_HEAD(&link->link); + link->pdev = pdev; + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM) { + struct pcie_link_state *parent; + parent = pdev->bus->parent->self->link_state; + if (!parent) { + kfree(link); + return NULL; + } + link->parent = parent; + list_add(&link->link, &parent->children); + } + /* Setup a pointer to the root port link */ + if (!link->parent) + link->root = link; + else + link->root = link->parent->root; + + list_add(&link->sibling, &link_list); + pdev->link_state = link; + return link; +} + /* * pcie_aspm_init_link_state: Initiate PCI express link state. - * It is called after the pcie and its children devices are scaned. + * It is called after the pcie and its children devices are scanned. * @pdev: the root port or switch downstream port */ void pcie_aspm_init_link_state(struct pci_dev *pdev) { - unsigned int state; - struct pcie_link_state *link_state; - int error = 0; + struct pcie_link_state *link; + int blacklist = !!pcie_aspm_sanity_check(pdev); - if (aspm_disabled || !pdev->is_pcie || pdev->link_state) + if (!aspm_support_enabled) return; - if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + + if (!pci_is_pcie(pdev) || pdev->link_state) + return; + if (pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT && + pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM) return; + + /* VIA has a strange chipset, root port is under a bridge */ + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT && + pdev->bus->self) + return; + down_read(&pci_bus_sem); if (list_empty(&pdev->subordinate->devices)) goto out; - if (pcie_aspm_sanity_check(pdev)) - goto out; - mutex_lock(&aspm_lock); + link = alloc_pcie_link_state(pdev); + if (!link) + goto unlock; + /* + * Setup initial ASPM state. Note that we need to configure + * upstream links also because capable state of them can be + * update through pcie_aspm_cap_init(). + */ + pcie_aspm_cap_init(link, blacklist); - link_state = kzalloc(sizeof(*link_state), GFP_KERNEL); - if (!link_state) - goto unlock_out; - pdev->link_state = link_state; - - pcie_aspm_configure_common_clock(pdev); - - pcie_aspm_cap_init(pdev); - - /* config link state to avoid BIOS error */ - state = pcie_aspm_check_state(pdev, policy_to_aspm_state(pdev)); - __pcie_aspm_config_link(pdev, state); - - pcie_check_clock_pm(pdev); + /* Setup initial Clock PM state */ + pcie_clkpm_cap_init(link, blacklist); - link_state->pdev = pdev; - list_add(&link_state->sibiling, &link_list); + /* + * At this stage drivers haven't had an opportunity to change the + * link policy setting. Enabling ASPM on broken hardware can cripple + * it even before the driver has had a chance to disable ASPM, so + * default to a safe level right now. If we're enabling ASPM beyond + * the BIOS's expectation, we'll do so once pci_enable_device() is + * called. + */ + if (aspm_policy != POLICY_POWERSAVE) { + pcie_config_aspm_path(link); + pcie_set_clkpm(link, policy_to_clkpm_state(link)); + } -unlock_out: - if (error) - free_link_state(pdev); +unlock: mutex_unlock(&aspm_lock); out: up_read(&pci_bus_sem); } +/* Recheck latencies and update aspm_capable for links under the root */ +static void pcie_update_aspm_capable(struct pcie_link_state *root) +{ + struct pcie_link_state *link; + BUG_ON(root->parent); + list_for_each_entry(link, &link_list, sibling) { + if (link->root != root) + continue; + link->aspm_capable = link->aspm_support; + } + list_for_each_entry(link, &link_list, sibling) { + struct pci_dev *child; + struct pci_bus *linkbus = link->pdev->subordinate; + if (link->root != root) + continue; + list_for_each_entry(child, &linkbus->devices, bus_list) { + if ((pci_pcie_type(child) != PCI_EXP_TYPE_ENDPOINT) && + (pci_pcie_type(child) != PCI_EXP_TYPE_LEG_END)) + continue; + pcie_aspm_check_latency(child); + } + } +} + /* @pdev: the endpoint device */ void pcie_aspm_exit_link_state(struct pci_dev *pdev) { struct pci_dev *parent = pdev->bus->self; - struct pcie_link_state *link_state = parent->link_state; + struct pcie_link_state *link, *root, *parent_link; - if (aspm_disabled || !pdev->is_pcie || !parent || !link_state) - return; - if (parent->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - parent->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + if (!parent || !parent->link_state) return; + down_read(&pci_bus_sem); mutex_lock(&aspm_lock); - /* * All PCIe functions are in one slot, remove one function will remove - * the the whole slot, so just wait + * the whole slot, so just wait until we are the last function left. */ - if (!list_empty(&parent->subordinate->devices)) + if (!list_is_last(&pdev->bus_list, &parent->subordinate->devices)) goto out; + link = parent->link_state; + root = link->root; + parent_link = link->parent; + /* All functions are removed, so just disable ASPM for the link */ - __pcie_aspm_config_one_dev(parent, 0); - list_del(&link_state->sibiling); + pcie_config_aspm_link(link, 0); + list_del(&link->sibling); + list_del(&link->link); /* Clock PM is for endpoint device */ + free_link_state(link); - free_link_state(parent); + /* Recheck latencies and configure upstream links */ + if (parent_link) { + pcie_update_aspm_capable(root); + pcie_config_aspm_path(parent_link); + } out: mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); @@ -623,59 +673,140 @@ out: /* @pdev: the root port or switch downstream port */ void pcie_aspm_pm_state_change(struct pci_dev *pdev) { - struct pcie_link_state *link_state = pdev->link_state; + struct pcie_link_state *link = pdev->link_state; - if (aspm_disabled || !pdev->is_pcie || !pdev->link_state) + if (aspm_disabled || !pci_is_pcie(pdev) || !link) return; - if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + if ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) && + (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM)) return; /* - * devices changed PM state, we should recheck if latency meets all - * functions' requirement + * Devices changed PM state, we should recheck if latency + * meets all functions' requirement */ - pcie_aspm_configure_link_state(pdev, link_state->enabled_state); + down_read(&pci_bus_sem); + mutex_lock(&aspm_lock); + pcie_update_aspm_capable(link->root); + pcie_config_aspm_path(link); + mutex_unlock(&aspm_lock); + up_read(&pci_bus_sem); } -/* - * pci_disable_link_state - disable pci device's link state, so the link will - * never enter specific states - */ -void pci_disable_link_state(struct pci_dev *pdev, int state) +void pcie_aspm_powersave_config_link(struct pci_dev *pdev) +{ + struct pcie_link_state *link = pdev->link_state; + + if (aspm_disabled || !pci_is_pcie(pdev) || !link) + return; + + if (aspm_policy != POLICY_POWERSAVE) + return; + + if ((pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT) && + (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM)) + return; + + down_read(&pci_bus_sem); + mutex_lock(&aspm_lock); + pcie_config_aspm_path(link); + pcie_set_clkpm(link, policy_to_clkpm_state(link)); + mutex_unlock(&aspm_lock); + up_read(&pci_bus_sem); +} + +static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem, + bool force) { struct pci_dev *parent = pdev->bus->self; - struct pcie_link_state *link_state; + struct pcie_link_state *link; - if (aspm_disabled || !pdev->is_pcie) + if (!pci_is_pcie(pdev)) return; - if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT || - pdev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM) + + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT || + pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM) parent = pdev; if (!parent || !parent->link_state) return; - down_read(&pci_bus_sem); + /* + * A driver requested that ASPM be disabled on this device, but + * if we don't have permission to manage ASPM (e.g., on ACPI + * systems we have to observe the FADT ACPI_FADT_NO_ASPM bit and + * the _OSC method), we can't honor that request. Windows has + * a similar mechanism using "PciASPMOptOut", which is also + * ignored in this situation. + */ + if (aspm_disabled && !force) { + dev_warn(&pdev->dev, "can't disable ASPM; OS doesn't have ASPM control\n"); + return; + } + + if (sem) + down_read(&pci_bus_sem); mutex_lock(&aspm_lock); - link_state = parent->link_state; - link_state->support_state &= - ~(state & (PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1)); - if (state & PCIE_LINK_STATE_CLKPM) - link_state->clk_pm_capable = 0; - - __pcie_aspm_configure_link_state(parent, link_state->enabled_state); - if (!link_state->clk_pm_capable && link_state->clk_pm_enabled) - pcie_set_clock_pm(parent, 0); + link = parent->link_state; + if (state & PCIE_LINK_STATE_L0S) + link->aspm_disable |= ASPM_STATE_L0S; + if (state & PCIE_LINK_STATE_L1) + link->aspm_disable |= ASPM_STATE_L1; + pcie_config_aspm_link(link, policy_to_aspm_state(link)); + + if (state & PCIE_LINK_STATE_CLKPM) { + link->clkpm_capable = 0; + pcie_set_clkpm(link, 0); + } mutex_unlock(&aspm_lock); - up_read(&pci_bus_sem); + if (sem) + up_read(&pci_bus_sem); +} + +void pci_disable_link_state_locked(struct pci_dev *pdev, int state) +{ + __pci_disable_link_state(pdev, state, false, false); +} +EXPORT_SYMBOL(pci_disable_link_state_locked); + +/** + * pci_disable_link_state - Disable device's link state, so the link will + * never enter specific states. Note that if the BIOS didn't grant ASPM + * control to the OS, this does nothing because we can't touch the LNKCTL + * register. + * + * @pdev: PCI device + * @state: ASPM link state to disable + */ +void pci_disable_link_state(struct pci_dev *pdev, int state) +{ + __pci_disable_link_state(pdev, state, true, false); } EXPORT_SYMBOL(pci_disable_link_state); +void pcie_clear_aspm(struct pci_bus *bus) +{ + struct pci_dev *child; + + if (aspm_force) + return; + + /* + * Clear any ASPM setup that the firmware has carried out on this bus + */ + list_for_each_entry(child, &bus->devices, bus_list) { + __pci_disable_link_state(child, PCIE_LINK_STATE_L0S | + PCIE_LINK_STATE_L1 | + PCIE_LINK_STATE_CLKPM, + false, true); + } +} + static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp) { int i; - struct pci_dev *pdev; - struct pcie_link_state *link_state; + struct pcie_link_state *link; + if (aspm_disabled) + return -EPERM; for (i = 0; i < ARRAY_SIZE(policy_str); i++) if (!strncmp(val, policy_str[i], strlen(policy_str[i]))) break; @@ -687,14 +818,9 @@ static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp) down_read(&pci_bus_sem); mutex_lock(&aspm_lock); aspm_policy = i; - list_for_each_entry(link_state, &link_list, sibiling) { - pdev = link_state->pdev; - __pcie_aspm_configure_link_state(pdev, - policy_to_aspm_state(pdev)); - if (link_state->clk_pm_capable && - link_state->clk_pm_enabled != policy_to_clkpm_state(pdev)) - pcie_set_clock_pm(pdev, policy_to_clkpm_state(pdev)); - + list_for_each_entry(link, &link_list, sibling) { + pcie_config_aspm_link(link, policy_to_aspm_state(link)); + pcie_set_clkpm(link, policy_to_clkpm_state(link)); } mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); @@ -723,7 +849,7 @@ static ssize_t link_state_show(struct device *dev, struct pci_dev *pci_device = to_pci_dev(dev); struct pcie_link_state *link_state = pci_device->link_state; - return sprintf(buf, "%d\n", link_state->enabled_state); + return sprintf(buf, "%d\n", link_state->aspm_enabled); } static ssize_t link_state_store(struct device *dev, @@ -731,19 +857,31 @@ static ssize_t link_state_store(struct device *dev, const char *buf, size_t n) { - struct pci_dev *pci_device = to_pci_dev(dev); - int state; + struct pci_dev *pdev = to_pci_dev(dev); + struct pcie_link_state *link, *root = pdev->link_state->root; + u32 val = buf[0] - '0', state = 0; - if (n < 1) + if (aspm_disabled) + return -EPERM; + if (n < 1 || val > 3) return -EINVAL; - state = buf[0]-'0'; - if (state >= 0 && state <= 3) { - /* setup link aspm state */ - pcie_aspm_configure_link_state(pci_device, state); - return n; - } - return -EINVAL; + /* Convert requested state to ASPM state */ + if (val & PCIE_LINK_STATE_L0S) + state |= ASPM_STATE_L0S; + if (val & PCIE_LINK_STATE_L1) + state |= ASPM_STATE_L1; + + down_read(&pci_bus_sem); + mutex_lock(&aspm_lock); + list_for_each_entry(link, &link_list, sibling) { + if (link->root != root) + continue; + pcie_config_aspm_link(link, state); + } + mutex_unlock(&aspm_lock); + up_read(&pci_bus_sem); + return n; } static ssize_t clk_ctl_show(struct device *dev, @@ -753,7 +891,7 @@ static ssize_t clk_ctl_show(struct device *dev, struct pci_dev *pci_device = to_pci_dev(dev); struct pcie_link_state *link_state = pci_device->link_state; - return sprintf(buf, "%d\n", link_state->clk_pm_enabled); + return sprintf(buf, "%d\n", link_state->clkpm_enabled); } static ssize_t clk_ctl_store(struct device *dev, @@ -761,7 +899,7 @@ static ssize_t clk_ctl_store(struct device *dev, const char *buf, size_t n) { - struct pci_dev *pci_device = to_pci_dev(dev); + struct pci_dev *pdev = to_pci_dev(dev); int state; if (n < 1) @@ -770,7 +908,7 @@ static ssize_t clk_ctl_store(struct device *dev, down_read(&pci_bus_sem); mutex_lock(&aspm_lock); - pcie_set_clock_pm(pci_device, !!state); + pcie_set_clkpm_nocheck(pdev->link_state, !!state); mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); @@ -785,14 +923,15 @@ void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) { struct pcie_link_state *link_state = pdev->link_state; - if (!pdev->is_pcie || (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) + if (!pci_is_pcie(pdev) || + (pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT && + pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) return; - if (link_state->support_state) + if (link_state->aspm_support) sysfs_add_file_to_group(&pdev->dev.kobj, &dev_attr_link_state.attr, power_group); - if (link_state->clk_pm_capable) + if (link_state->clkpm_capable) sysfs_add_file_to_group(&pdev->dev.kobj, &dev_attr_clk_ctl.attr, power_group); } @@ -801,14 +940,15 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) { struct pcie_link_state *link_state = pdev->link_state; - if (!pdev->is_pcie || (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) + if (!pci_is_pcie(pdev) || + (pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT && + pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM) || !link_state) return; - if (link_state->support_state) + if (link_state->aspm_support) sysfs_remove_file_from_group(&pdev->dev.kobj, &dev_attr_link_state.attr, power_group); - if (link_state->clk_pm_capable) + if (link_state->clkpm_capable) sysfs_remove_file_from_group(&pdev->dev.kobj, &dev_attr_clk_ctl.attr, power_group); } @@ -817,11 +957,13 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) static int __init pcie_aspm_disable(char *str) { if (!strcmp(str, "off")) { + aspm_policy = POLICY_DEFAULT; aspm_disabled = 1; + aspm_support_enabled = false; printk(KERN_INFO "PCIe ASPM is disabled\n"); } else if (!strcmp(str, "force")) { aspm_force = 1; - printk(KERN_INFO "PCIe ASPM is forcedly enabled\n"); + printk(KERN_INFO "PCIe ASPM is forcibly enabled\n"); } return 1; } @@ -830,28 +972,20 @@ __setup("pcie_aspm=", pcie_aspm_disable); void pcie_no_aspm(void) { - if (!aspm_force) + /* + * Disabling ASPM is intended to prevent the kernel from modifying + * existing hardware state, not to clear existing state. To that end: + * (a) set policy to POLICY_DEFAULT in order to avoid changing state + * (b) prevent userspace from changing policy + */ + if (!aspm_force) { + aspm_policy = POLICY_DEFAULT; aspm_disabled = 1; + } } -#ifdef CONFIG_ACPI -#include <acpi/acpi_bus.h> -#include <linux/pci-acpi.h> -static void pcie_aspm_platform_init(void) +bool pcie_aspm_support_enabled(void) { - pcie_osc_support_set(OSC_ACTIVE_STATE_PWR_SUPPORT| - OSC_CLOCK_PWR_CAPABILITY_SUPPORT); + return aspm_support_enabled; } -#else -static inline void pcie_aspm_platform_init(void) { } -#endif - -static int __init pcie_aspm_init(void) -{ - if (aspm_disabled) - return 0; - pcie_aspm_platform_init(); - return 0; -} - -fs_initcall(pcie_aspm_init); +EXPORT_SYMBOL(pcie_aspm_support_enabled); |