diff options
Diffstat (limited to 'drivers/pci/pcie/aspm.c')
| -rw-r--r-- | drivers/pci/pcie/aspm.c | 787 |
1 files changed, 371 insertions, 416 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index b0367f168af4..3d27c97e0486 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -26,40 +26,36 @@ #endif #define MODULE_PARAM_PREFIX "pcie_aspm." -struct endpoint_state { - unsigned int l0s_acceptable_latency; - unsigned int l1_acceptable_latency; +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; - bool downstream_has_switch; - - struct pcie_link_state *parent; - struct list_head children; - struct list_head link; + 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:2; /* Supported ASPM state */ + u32 aspm_enabled:2; /* Enabled ASPM state */ + u32 aspm_default:2; /* Default ASPM state by BIOS */ + + /* 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 */ + /* Latencies */ + struct aspm_latency latency; /* 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; @@ -78,27 +74,23 @@ static const char *policy_str[] = { #define LINK_RETRAIN_TIMEOUT HZ -static int policy_to_aspm_state(struct pci_dev *pdev) +static int policy_to_aspm_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 */ return 0; case POLICY_POWERSAVE: /* Enable ASPM L0s/L1 */ - return PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1; + return PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1; 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 */ @@ -107,73 +99,78 @@ 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); + list_for_each_entry(child, &linkbus->devices, bus_list) { + pos = pci_find_capability(child, PCI_CAP_ID_EXP); if (!pos) return; - pci_read_config_word(child_dev, pos + PCI_EXP_LNKCTL, ®16); + pci_read_config_word(child, pos + PCI_EXP_LNKCTL, ®16); if (enable) reg16 |= PCI_EXP_LNKCTL_CLKREQ_EN; else reg16 &= ~PCI_EXP_LNKCTL_CLKREQ_EN; - pci_write_config_word(child_dev, pos + PCI_EXP_LNKCTL, reg16); + pci_write_config_word(child, pos + PCI_EXP_LNKCTL, reg16); } - link_state->clk_pm_enabled = !!enable; + link->clkpm_enabled = !!enable; } -static void pcie_check_clock_pm(struct pci_dev *pdev, int blacklist) +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) + return; + /* 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 pos, 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); + list_for_each_entry(child, &linkbus->devices, bus_list) { + pos = pci_find_capability(child, PCI_CAP_ID_EXP); if (!pos) return; - pci_read_config_dword(child_dev, pos + PCI_EXP_LNKCAP, ®32); + pci_read_config_dword(child, pos + 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); + pci_read_config_word(child, pos + PCI_EXP_LNKCTL, ®16); if (!(reg16 & PCI_EXP_LNKCTL_CLKREQ_EN)) enabled = 0; } - link_state->clk_pm_enabled = enabled; - link_state->bios_clk_state = enabled; - if (!blacklist) { - link_state->clk_pm_capable = capable; - pcie_set_clock_pm(pdev, policy_to_clkpm_state(pdev)); - } else { - link_state->clk_pm_capable = 0; - pcie_set_clock_pm(pdev, 0); - } + link->clkpm_enabled = enabled; + link->clkpm_default = enabled; + link->clkpm_capable = (blacklist) ? 0 : capable; } -static bool pcie_aspm_downstream_has_switch(struct pci_dev *pdev) +static bool pcie_aspm_downstream_has_switch(struct pcie_link_state *link) { - struct pci_dev *child_dev; + struct pci_dev *child; + struct pci_bus *linkbus = link->pdev->subordinate; - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - if (child_dev->pcie_type == PCI_EXP_TYPE_UPSTREAM) + list_for_each_entry(child, &linkbus->devices, bus_list) { + if (child->pcie_type == PCI_EXP_TYPE_UPSTREAM) return true; } return false; @@ -184,289 +181,263 @@ static bool pcie_aspm_downstream_has_switch(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, i = 0; - u16 reg16 = 0; - struct pci_dev *child_dev; - int same_clock = 1; + int ppos, cpos, same_clock = 1; + u16 reg16, parent_reg, child_reg[8]; unsigned long start_jiffies; - u16 child_regs[8], parent_reg; + 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(!child->is_pcie); /* 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); + cpos = pci_find_capability(child, PCI_CAP_ID_EXP); + pci_read_config_word(child, cpos + 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); + ppos = pci_find_capability(parent, PCI_CAP_ID_EXP); + pci_read_config_word(parent, ppos + 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); - child_regs[i] = reg16; + list_for_each_entry(child, &linkbus->devices, bus_list) { + cpos = pci_find_capability(child, PCI_CAP_ID_EXP); + pci_read_config_word(child, cpos + 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); - i++; + pci_write_config_word(child, cpos + PCI_EXP_LNKCTL, reg16); } /* Configure upstream component */ - pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); + pci_read_config_word(parent, ppos + 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); + pci_write_config_word(parent, ppos + PCI_EXP_LNKCTL, reg16); - /* retrain link */ + /* Retrain link */ reg16 |= PCI_EXP_LNKCTL_RL; - pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); + pci_write_config_word(parent, ppos + PCI_EXP_LNKCTL, reg16); - /* Wait for link training end */ - /* break out after waiting for timeout */ + /* Wait for link training end. Break out after waiting for timeout */ start_jiffies = jiffies; for (;;) { - pci_read_config_word(pdev, pos + PCI_EXP_LNKSTA, ®16); + pci_read_config_word(parent, ppos + PCI_EXP_LNKSTA, ®16); if (!(reg16 & PCI_EXP_LNKSTA_LT)) break; if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) break; msleep(1); } - /* training failed -> recover */ - if (reg16 & PCI_EXP_LNKSTA_LT) { - dev_printk (KERN_ERR, &pdev->dev, "ASPM: Could not configure" - " common clock\n"); - i = 0; - list_for_each_entry(child_dev, &pdev->subordinate->devices, - bus_list) { - child_pos = pci_find_capability(child_dev, - PCI_CAP_ID_EXP); - pci_write_config_word(child_dev, - child_pos + PCI_EXP_LNKCTL, - child_regs[i]); - i++; - } - pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, parent_reg); + if (!(reg16 & PCI_EXP_LNKSTA_LT)) + return; + + /* Training failed. Restore common clock configurations */ + dev_printk(KERN_ERR, &parent->dev, + "ASPM: Could not configure common clock\n"); + list_for_each_entry(child, &linkbus->devices, bus_list) { + cpos = pci_find_capability(child, PCI_CAP_ID_EXP); + pci_write_config_word(child, cpos + PCI_EXP_LNKCTL, + child_reg[PCI_FUNC(child->devfn)]); } + pci_write_config_word(parent, ppos + 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) + u32 *l0s, u32 *l1, u32 *enabled) { int pos; u16 reg16; - u32 reg32; - unsigned int latency; + u32 reg32, encoding; + *l0s = *l1 = *enabled = 0; 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 != (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); + encoding = (reg32 & PCI_EXP_LNKCAP_L0SEL) >> 12; + *l0s = calc_l0s_latency(encoding); if (*state & PCIE_LINK_STATE_L1) { - latency = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15; - *l1 = calc_L1_latency(latency, 0); + encoding = (reg32 & PCI_EXP_LNKCAP_L1EL) >> 15; + *l1 = calc_l1_latency(encoding); } pci_read_config_word(pdev, pos + PCI_EXP_LNKCTL, ®16); - *enabled = reg16 & (PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1); + *enabled = reg16 & (PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1); } -static void pcie_aspm_cap_init(struct pci_dev *pdev) +static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) { - struct pci_dev *child_dev; - u32 state, tmp; - struct pcie_link_state *link_state = pdev->link_state; + u32 support, l0s, l1, enabled; + struct pci_dev *child, *parent = link->pdev; + struct pci_bus *linkbus = parent->subordinate; + + if (blacklist) { + /* Set support state to 0, so we will disable ASPM later */ + link->aspm_support = 0; + link->aspm_default = 0; + link->aspm_enabled = PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1; + return; + } + + /* Configure common clock before checking latencies */ + pcie_aspm_configure_common_clock(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); + pcie_aspm_get_cap_device(parent, &support, &l0s, &l1, &enabled); + link->aspm_support = support; + link->latency.l0s = l0s; + link->latency.l1 = l1; + link->aspm_enabled = enabled; + /* 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) + child = list_entry(linkbus->devices.next, struct pci_dev, bus_list); + pcie_aspm_get_cap_device(child, &support, &l0s, &l1, &enabled); + link->aspm_support &= support; + link->latency.l0s = max_t(u32, link->latency.l0s, l0s); + link->latency.l1 = max_t(u32, link->latency.l1, l1); + + if (!link->aspm_support) return; - link_state->enabled_state &= link_state->support_state; - link_state->bios_aspm_state = link_state->enabled_state; + + link->aspm_enabled &= link->aspm_support; + link->aspm_default = link->aspm_enabled; /* ENDPOINT states*/ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { + list_for_each_entry(child, &linkbus->devices, bus_list) { int pos; - u32 reg32; - unsigned int latency; - struct endpoint_state *ep_state = - &link_state->endpoints[PCI_FUNC(child_dev->devfn)]; + u32 reg32, encoding; + struct aspm_latency *acceptable = + &link->acceptable[PCI_FUNC(child->devfn)]; - if (child_dev->pcie_type != PCI_EXP_TYPE_ENDPOINT && - child_dev->pcie_type != PCI_EXP_TYPE_LEG_END) + if (child->pcie_type != PCI_EXP_TYPE_ENDPOINT && + child->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; + pos = pci_find_capability(child, PCI_CAP_ID_EXP); + pci_read_config_dword(child, pos + PCI_EXP_DEVCAP, ®32); + encoding = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6; + acceptable->l0s = calc_l0s_acceptable(encoding); + if (link->aspm_support & PCIE_LINK_STATE_L1) { + encoding = (reg32 & PCI_EXP_DEVCAP_L1) >> 9; + acceptable->l1 = calc_l1_acceptable(encoding); } } } -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; - - 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 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; - } +/** + * __pcie_aspm_check_state_one - check latency for endpoint device. + * @endpoint: pointer to the struct pci_dev of 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. + */ +static u32 __pcie_aspm_check_state_one(struct pci_dev *endpoint, u32 state) +{ + u32 l1_switch_latency = 0; + struct aspm_latency *acceptable; + struct pcie_link_state *link; + + link = endpoint->bus->self->link_state; + state &= link->aspm_support; + acceptable = &link->acceptable[PCI_FUNC(endpoint->devfn)]; + + while (link && state) { + if ((state & PCIE_LINK_STATE_L0S) && + (link->latency.l0s > acceptable->l0s)) + state &= ~PCIE_LINK_STATE_L0S; + if ((state & PCIE_LINK_STATE_L1) && + (link->latency.l1 + l1_switch_latency > acceptable->l1)) + state &= ~PCIE_LINK_STATE_L1; + link = link->parent; + /* + * Every switch on the path to root complex need 1 + * more microsecond for L1. Spec doesn't mention L0s. + */ + l1_switch_latency += 1000; } return state; } -static unsigned int pcie_aspm_check_state(struct pci_dev *pdev, - unsigned int state) +static u32 pcie_aspm_check_state(struct pcie_link_state *link, u32 state) { - struct pci_dev *child_dev; + pci_power_t power_state; + struct pci_dev *child; + struct pci_bus *linkbus = link->pdev->subordinate; /* If no child, ignore the link */ - if (list_empty(&pdev->subordinate->devices)) + if (list_empty(&linkbus->devices)) return state; - 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)) + + list_for_each_entry(child, &linkbus->devices, bus_list) { + /* + * If downstream component of a link is pci bridge, we + * disable ASPM for now for the link + */ + if (child->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) + return 0; + + if ((child->pcie_type != PCI_EXP_TYPE_ENDPOINT && + child->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) + power_state = child->current_state; + if (power_state == PCI_D1 || power_state == PCI_D2 || + power_state == PCI_D3hot || power_state == PCI_D3cold) continue; - state = __pcie_aspm_check_state_one(child_dev, state); + state = __pcie_aspm_check_state_one(child, state); } return state; } @@ -482,90 +453,71 @@ static void __pcie_aspm_config_one_dev(struct pci_dev *pdev, unsigned int state) pci_write_config_word(pdev, pos + PCI_EXP_LNKCTL, reg16); } -static void __pcie_aspm_config_link(struct pci_dev *pdev, unsigned int state) +static void __pcie_aspm_config_link(struct pcie_link_state *link, u32 state) { - struct pci_dev *child_dev; - int valid = 1; - struct pcie_link_state *link_state = pdev->link_state; + struct pci_dev *child, *parent = link->pdev; + struct pci_bus *linkbus = parent->subordinate; /* If no child, disable the link */ - if (list_empty(&pdev->subordinate->devices)) + if (list_empty(&linkbus->devices)) state = 0; /* - * if the downstream component has pci bridge function, don't do ASPM - * now + * If the downstream component has pci bridge function, don't + * do ASPM now. */ - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) { - if (child_dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) { - valid = 0; - break; - } + list_for_each_entry(child, &linkbus->devices, bus_list) { + if (child->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) + return; } - 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. + * 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); + __pcie_aspm_config_one_dev(parent, state); - list_for_each_entry(child_dev, &pdev->subordinate->devices, bus_list) - __pcie_aspm_config_one_dev(child_dev, state); + list_for_each_entry(child, &linkbus->devices, bus_list) + __pcie_aspm_config_one_dev(child, state); if (!(state & PCIE_LINK_STATE_L1)) - __pcie_aspm_config_one_dev(pdev, state); + __pcie_aspm_config_one_dev(parent, state); - link_state->enabled_state = state; + link->aspm_enabled = state; } -static struct pcie_link_state *get_root_port_link(struct pcie_link_state *link) +/* Check the whole hierarchy, and configure each link in the hierarchy */ +static void __pcie_aspm_configure_link_state(struct pcie_link_state *link, + u32 state) { - struct pcie_link_state *root_port_link = link; - while (root_port_link->parent) - root_port_link = root_port_link->parent; - return root_port_link; -} + struct pcie_link_state *leaf, *root = link->root; -/* check the whole hierarchy, and configure each link in the hierarchy */ -static void __pcie_aspm_configure_link_state(struct pci_dev *pdev, - unsigned int state) -{ - struct pcie_link_state *link_state = pdev->link_state; - struct pcie_link_state *root_port_link = get_root_port_link(link_state); - struct pcie_link_state *leaf; + state &= (PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1); - state &= PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1; - - /* check all links who have specific root port link */ - list_for_each_entry(leaf, &link_list, sibiling) { - if (!list_empty(&leaf->children) || - get_root_port_link(leaf) != root_port_link) + /* Check all links who have specific root port link */ + list_for_each_entry(leaf, &link_list, sibling) { + if (!list_empty(&leaf->children) || (leaf->root != root)) continue; - state = pcie_aspm_check_state(leaf->pdev, state); + state = pcie_aspm_check_state(leaf, state); } - /* check root port link too in case it hasn't children */ - state = pcie_aspm_check_state(root_port_link->pdev, state); - - if (link_state->enabled_state == state) + /* Check root port link too in case it hasn't children */ + state = pcie_aspm_check_state(root, state); + if (link->aspm_enabled == state) return; - /* - * we must change the hierarchy. See comments in + * We must change the hierarchy. See comments in * __pcie_aspm_config_link for the order **/ if (state & PCIE_LINK_STATE_L1) { - list_for_each_entry(leaf, &link_list, sibiling) { - if (get_root_port_link(leaf) == root_port_link) - __pcie_aspm_config_link(leaf->pdev, state); + list_for_each_entry(leaf, &link_list, sibling) { + if (leaf->root == root) + __pcie_aspm_config_link(leaf, state); } } else { - list_for_each_entry_reverse(leaf, &link_list, sibiling) { - if (get_root_port_link(leaf) == root_port_link) - __pcie_aspm_config_link(leaf->pdev, state); + list_for_each_entry_reverse(leaf, &link_list, sibling) { + if (leaf->root == root) + __pcie_aspm_config_link(leaf, state); } } } @@ -574,45 +526,42 @@ static void __pcie_aspm_configure_link_state(struct pci_dev *pdev, * 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_aspm_configure_link_state(struct pcie_link_state *link, + u32 state) { down_read(&pci_bus_sem); mutex_lock(&aspm_lock); - __pcie_aspm_configure_link_state(pdev, state); + __pcie_aspm_configure_link_state(link, state); mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); } -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; + int pos; 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) { + pos = pci_find_capability(child, PCI_CAP_ID_EXP); + if (!pos) return -EINVAL; - /* * 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); + pci_read_config_dword(child, pos + PCI_EXP_DEVCAP, ®32); if (!(reg32 & PCI_EXP_DEVCAP_RBER) && !aspm_force) { - dev_printk(KERN_INFO, &child_dev->dev, "disabling ASPM" + dev_printk(KERN_INFO, &child->dev, "disabling ASPM" " on pre-1.1 PCIe device. You can enable it" " with 'pcie_aspm=force'\n"); return -EINVAL; @@ -621,6 +570,47 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev) return 0; } +static struct pcie_link_state *pcie_aspm_setup_link_state(struct pci_dev *pdev) +{ + struct pcie_link_state *link; + int blacklist = !!pcie_aspm_sanity_check(pdev); + + 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 (pdev->pcie_type == 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; + + /* Check ASPM capability */ + pcie_aspm_cap_init(link, blacklist); + + /* Check Clock PM capability */ + pcie_clkpm_cap_init(link, blacklist); + + return link; +} + /* * pcie_aspm_init_link_state: Initiate PCI express link state. * It is called after the pcie and its children devices are scaned. @@ -628,75 +618,47 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev) */ void pcie_aspm_init_link_state(struct pci_dev *pdev) { - unsigned int state; - struct pcie_link_state *link_state; - int error = 0; - int blacklist; + u32 state; + struct pcie_link_state *link; if (aspm_disabled || !pdev->is_pcie || pdev->link_state) return; if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && - pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + return; + + /* VIA has a strange chipset, root port is under a bridge */ + if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT && + pdev->bus->self) return; + down_read(&pci_bus_sem); if (list_empty(&pdev->subordinate->devices)) goto out; - blacklist = !!pcie_aspm_sanity_check(pdev); - mutex_lock(&aspm_lock); - - link_state = kzalloc(sizeof(*link_state), GFP_KERNEL); - if (!link_state) - goto unlock_out; - - link_state->downstream_has_switch = pcie_aspm_downstream_has_switch(pdev); - INIT_LIST_HEAD(&link_state->children); - INIT_LIST_HEAD(&link_state->link); - if (pdev->bus->self) {/* this is a switch */ - struct pcie_link_state *parent_link_state; - - parent_link_state = pdev->bus->parent->self->link_state; - if (!parent_link_state) { - kfree(link_state); - goto unlock_out; - } - list_add(&link_state->link, &parent_link_state->children); - link_state->parent = parent_link_state; - } - - pdev->link_state = link_state; - - if (!blacklist) { - pcie_aspm_configure_common_clock(pdev); - pcie_aspm_cap_init(pdev); + link = pcie_aspm_setup_link_state(pdev); + if (!link) + goto unlock; + /* + * Setup initial ASPM state + * + * If link has switch, delay the link config. The leaf link + * initialization will config the whole hierarchy. But we must + * make sure BIOS doesn't set unsupported link state. + */ + if (pcie_aspm_downstream_has_switch(link)) { + state = pcie_aspm_check_state(link, link->aspm_default); + __pcie_aspm_config_link(link, state); } else { - link_state->enabled_state = PCIE_LINK_STATE_L0S|PCIE_LINK_STATE_L1; - link_state->bios_aspm_state = 0; - /* Set support state to 0, so we will disable ASPM later */ - link_state->support_state = 0; + state = policy_to_aspm_state(link); + __pcie_aspm_configure_link_state(link, state); } - link_state->pdev = pdev; - list_add(&link_state->sibiling, &link_list); - - if (link_state->downstream_has_switch) { - /* - * If link has switch, delay the link config. The leaf link - * initialization will config the whole hierarchy. but we must - * make sure BIOS doesn't set unsupported link state - **/ - state = pcie_aspm_check_state(pdev, link_state->bios_aspm_state); - __pcie_aspm_config_link(pdev, state); - } else - __pcie_aspm_configure_link_state(pdev, - policy_to_aspm_state(pdev)); - - pcie_check_clock_pm(pdev, blacklist); - -unlock_out: - if (error) - free_link_state(pdev); + /* Setup initial Clock PM state */ + state = (link->clkpm_capable) ? policy_to_clkpm_state(link) : 0; + pcie_set_clkpm(link, state); +unlock: mutex_unlock(&aspm_lock); out: up_read(&pci_bus_sem); @@ -725,11 +687,11 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev) /* All functions are removed, so just disable ASPM for the link */ __pcie_aspm_config_one_dev(parent, 0); - list_del(&link_state->sibiling); + list_del(&link_state->sibling); list_del(&link_state->link); /* Clock PM is for endpoint device */ - free_link_state(parent); + free_link_state(link_state); out: mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); @@ -749,7 +711,7 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev) * devices changed PM state, we should recheck if latency meets all * functions' requirement */ - pcie_aspm_configure_link_state(pdev, link_state->enabled_state); + pcie_aspm_configure_link_state(link_state, link_state->aspm_enabled); } /* @@ -772,14 +734,12 @@ void pci_disable_link_state(struct pci_dev *pdev, int state) 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_state->aspm_support &= ~state; + __pcie_aspm_configure_link_state(link_state, link_state->aspm_enabled); + if (state & PCIE_LINK_STATE_CLKPM) { + link_state->clkpm_capable = 0; + pcie_set_clkpm(link_state, 0); + } mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); } @@ -788,7 +748,6 @@ EXPORT_SYMBOL(pci_disable_link_state); 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; for (i = 0; i < ARRAY_SIZE(policy_str); i++) @@ -802,14 +761,10 @@ 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_state, &link_list, sibling) { + __pcie_aspm_configure_link_state(link_state, + policy_to_aspm_state(link_state)); + pcie_set_clkpm(link_state, policy_to_clkpm_state(link_state)); } mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); @@ -838,7 +793,7 @@ 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, @@ -846,7 +801,7 @@ static ssize_t link_state_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) @@ -854,7 +809,7 @@ static ssize_t link_state_store(struct device *dev, state = buf[0]-'0'; if (state >= 0 && state <= 3) { /* setup link aspm state */ - pcie_aspm_configure_link_state(pci_device, state); + pcie_aspm_configure_link_state(pdev->link_state, state); return n; } @@ -868,7 +823,7 @@ 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, @@ -876,7 +831,7 @@ 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) @@ -885,7 +840,7 @@ 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); @@ -904,10 +859,10 @@ void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev) pdev->pcie_type != 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); } @@ -920,10 +875,10 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev) pdev->pcie_type != 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); } |
