All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bjorn Helgaas <helgaas@kernel.org>
To: Vidya Sagar <vidyas@nvidia.com>
Cc: "Kenneth R . Crudup" <kenny@panix.com>,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	Bjorn Helgaas <bhelgaas@google.com>
Subject: [PATCH] Revert "PCI/ASPM: Save/restore L1SS Capability for suspend/resume"
Date: Wed, 27 Jan 2021 10:04:49 -0600	[thread overview]
Message-ID: <20210127160449.2990506-1-helgaas@kernel.org> (raw)

From: Bjorn Helgaas <bhelgaas@google.com>

This reverts commit 4257f7e008ea394fcecc050f1569c3503b8bcc15.

Kenneth reported that after 4257f7e008ea, he sees a torrent of disk I/O
errors on his NVMe device, and possibly other devices, until a reboot.

Link: https://lore.kernel.org/linux-pci/20201228040513.GA611645@bjorn-Precision-5520/
Reported-by: Kenneth R. Crudup <kenny@panix.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
This is tentative, pending a better fix for the issue.

 drivers/pci/pci.c       |  7 -------
 drivers/pci/pci.h       |  4 ----
 drivers/pci/pcie/aspm.c | 44 -----------------------------------------
 3 files changed, 55 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index b9fecc25d213..790393d1e318 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1558,7 +1558,6 @@ int pci_save_state(struct pci_dev *dev)
 		return i;
 
 	pci_save_ltr_state(dev);
-	pci_save_aspm_l1ss_state(dev);
 	pci_save_dpc_state(dev);
 	pci_save_aer_state(dev);
 	pci_save_ptm_state(dev);
@@ -1665,7 +1664,6 @@ void pci_restore_state(struct pci_dev *dev)
 	 * LTR itself (in the PCIe capability).
 	 */
 	pci_restore_ltr_state(dev);
-	pci_restore_aspm_l1ss_state(dev);
 
 	pci_restore_pcie_state(dev);
 	pci_restore_pasid_state(dev);
@@ -3353,11 +3351,6 @@ void pci_allocate_cap_save_buffers(struct pci_dev *dev)
 	if (error)
 		pci_err(dev, "unable to allocate suspend buffer for LTR\n");
 
-	error = pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_L1SS,
-					    2 * sizeof(u32));
-	if (error)
-		pci_err(dev, "unable to allocate suspend buffer for ASPM-L1SS\n");
-
 	pci_allocate_vc_save_buffers(dev);
 }
 
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 5c59365092fa..a7bdf0b1d45d 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -582,15 +582,11 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev);
 void pcie_aspm_exit_link_state(struct pci_dev *pdev);
 void pcie_aspm_pm_state_change(struct pci_dev *pdev);
 void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
-void pci_save_aspm_l1ss_state(struct pci_dev *dev);
-void pci_restore_aspm_l1ss_state(struct pci_dev *dev);
 #else
 static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
 static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { }
 static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
 static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
-static inline void pci_save_aspm_l1ss_state(struct pci_dev *dev) { }
-static inline void pci_restore_aspm_l1ss_state(struct pci_dev *dev) { }
 #endif
 
 #ifdef CONFIG_PCIE_ECRC
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index a08e7d6dc248..ac0557a305af 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -734,50 +734,6 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
 				PCI_L1SS_CTL1_L1SS_MASK, val);
 }
 
-void pci_save_aspm_l1ss_state(struct pci_dev *dev)
-{
-	int aspm_l1ss;
-	struct pci_cap_saved_state *save_state;
-	u32 *cap;
-
-	if (!pci_is_pcie(dev))
-		return;
-
-	aspm_l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
-	if (!aspm_l1ss)
-		return;
-
-	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_L1SS);
-	if (!save_state)
-		return;
-
-	cap = (u32 *)&save_state->cap.data[0];
-	pci_read_config_dword(dev, aspm_l1ss + PCI_L1SS_CTL1, cap++);
-	pci_read_config_dword(dev, aspm_l1ss + PCI_L1SS_CTL2, cap++);
-}
-
-void pci_restore_aspm_l1ss_state(struct pci_dev *dev)
-{
-	int aspm_l1ss;
-	struct pci_cap_saved_state *save_state;
-	u32 *cap;
-
-	if (!pci_is_pcie(dev))
-		return;
-
-	aspm_l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
-	if (!aspm_l1ss)
-		return;
-
-	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_L1SS);
-	if (!save_state)
-		return;
-
-	cap = (u32 *)&save_state->cap.data[0];
-	pci_write_config_dword(dev, aspm_l1ss + PCI_L1SS_CTL1, *cap++);
-	pci_write_config_dword(dev, aspm_l1ss + PCI_L1SS_CTL2, *cap++);
-}
-
 static void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val)
 {
 	pcie_capability_clear_and_set_word(pdev, PCI_EXP_LNKCTL,
-- 
2.25.1


                 reply	other threads:[~2021-01-27 16:08 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210127160449.2990506-1-helgaas@kernel.org \
    --to=helgaas@kernel.org \
    --cc=bhelgaas@google.com \
    --cc=kenny@panix.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=vidyas@nvidia.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.