From: Bjorn Helgaas <helgaas@kernel.org>
To: Sean Christopherson <seanjc@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
David Matlack <dmatlack@google.com>,
Vipin Sharma <vipinsh@google.com>,
Aaron Lewis <aaronlewis@google.com>
Subject: Re: [PATCH v2] PCI: Support Immediate Readiness on devices without PM capabilities
Date: Tue, 22 Jul 2025 18:03:21 -0500 [thread overview]
Message-ID: <20250722230321.GA2861805@bhelgaas> (raw)
In-Reply-To: <20250722155926.352248-1-seanjc@google.com>
On Tue, Jul 22, 2025 at 08:59:26AM -0700, Sean Christopherson wrote:
> Query support for Immediate Readiness irrespective of whether or not the
> device supports PM capabilities, as nothing in the PCIe spec suggests that
> Immediate Readiness is in any way dependent on PM functionality.
>
> Fixes: d6112f8def51 ("PCI: Add support for Immediate Readiness")
> Cc: David Matlack <dmatlack@google.com>
> Cc: Vipin Sharma <vipinsh@google.com>
> Cc: Aaron Lewis <aaronlewis@google.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
Applied to pci/enumeration for v6.17, thanks!
> ---
>
> v2: Move logic to pci_init_capabilities() instead of piggybacking the
> PM initialization code. [Vipin, Bjorn]
>
> v1 [RFC]: https://lore.kernel.org/all/20250624171637.485616-1-seanjc@google.com
>
> drivers/pci/pci.c | 4 ----
> drivers/pci/probe.c | 10 ++++++++++
> 2 files changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 9e42090fb108..4a1ba5c017cd 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -3205,7 +3205,6 @@ void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
> void pci_pm_init(struct pci_dev *dev)
> {
> int pm;
> - u16 status;
> u16 pmc;
>
> device_enable_async_suspend(&dev->dev);
> @@ -3266,9 +3265,6 @@ void pci_pm_init(struct pci_dev *dev)
> pci_pme_active(dev, false);
> }
>
> - pci_read_config_word(dev, PCI_STATUS, &status);
> - if (status & PCI_STATUS_IMM_READY)
> - dev->imm_ready = 1;
> poweron:
> pci_pm_power_up_and_verify_state(dev);
> pm_runtime_forbid(&dev->dev);
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 4b8693ec9e4c..d33b8af37247 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -2595,6 +2595,15 @@ void pcie_report_downtraining(struct pci_dev *dev)
> __pcie_print_link_status(dev, false);
> }
>
> +static void pci_imm_ready_init(struct pci_dev *dev)
> +{
> + u16 status;
> +
> + pci_read_config_word(dev, PCI_STATUS, &status);
> + if (status & PCI_STATUS_IMM_READY)
> + dev->imm_ready = 1;
> +}
> +
> static void pci_init_capabilities(struct pci_dev *dev)
> {
> pci_ea_init(dev); /* Enhanced Allocation */
> @@ -2604,6 +2613,7 @@ static void pci_init_capabilities(struct pci_dev *dev)
> /* Buffers for saving PCIe and PCI-X capabilities */
> pci_allocate_cap_save_buffers(dev);
>
> + pci_imm_ready_init(dev); /* Immediate Ready */
> pci_pm_init(dev); /* Power Management */
> pci_vpd_init(dev); /* Vital Product Data */
> pci_configure_ari(dev); /* Alternative Routing-ID Forwarding */
>
> base-commit: 89be9a83ccf1f88522317ce02f854f30d6115c41
> --
> 2.50.0.727.gbf7dc18ff4-goog
>
prev parent reply other threads:[~2025-07-22 23:03 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-22 15:59 [PATCH v2] PCI: Support Immediate Readiness on devices without PM capabilities Sean Christopherson
2025-07-22 23:03 ` Bjorn Helgaas [this message]
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