From 7720fd9c679ec839448480ad5cc548570a97bbf7 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Sat, 5 Oct 2019 14:03:57 +0200 Subject: [PATCH] PCI/ASPM: Allow re-enabling Clock PM [ Upstream commit 35efea32b26f9aacc99bf07e0d2cdfba2028b099 ] Previously Clock PM could not be re-enabled after being disabled by pci_disable_link_state() because clkpm_capable was reset. Change this by adding a clkpm_disable field similar to aspm_disable. Link: https://lore.kernel.org/r/4e8a66db-7d53-4a66-c26c-f0037ffaa705@gmail.com Signed-off-by: Heiner Kallweit Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin --- drivers/pci/pcie/aspm.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 32c3433..5a1bbf2c 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -64,6 +64,7 @@ struct pcie_link_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 */ + u32 clkpm_disable:1; /* Clock PM disabled */ /* Exit latencies */ struct aspm_latency latency_up; /* Upstream direction exit latency */ @@ -161,8 +162,11 @@ static void pcie_set_clkpm_nocheck(struct pcie_link_state *link, int enable) static void pcie_set_clkpm(struct pcie_link_state *link, int enable) { - /* Don't enable Clock PM if the link is not Clock PM capable */ - if (!link->clkpm_capable) + /* + * Don't enable Clock PM if the link is not Clock PM capable + * or Clock PM is disabled + */ + if (!link->clkpm_capable || link->clkpm_disable) enable = 0; /* Need nothing if the specified equals to current state */ if (link->clkpm_enabled == enable) @@ -192,7 +196,8 @@ static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist) } link->clkpm_enabled = enabled; link->clkpm_default = enabled; - link->clkpm_capable = (blacklist) ? 0 : capable; + link->clkpm_capable = capable; + link->clkpm_disable = blacklist ? 1 : 0; } static bool pcie_retrain_link(struct pcie_link_state *link) @@ -1097,10 +1102,9 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem) 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); - } + if (state & PCIE_LINK_STATE_CLKPM) + link->clkpm_disable = 1; + pcie_set_clkpm(link, policy_to_clkpm_state(link)); mutex_unlock(&aspm_lock); if (sem) up_read(&pci_bus_sem); -- 2.7.4