Re: [PATCH v6 6/6] PCI: spacemit-k1: Add Spacemit K3 PCIe host controller support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] pci: mmio access before clocks and resets are enabled causes crash
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commit f8b3a671e2cd8186deb7de2df88df163e1636aa6
Author: Inochi Amaoto <inochiama@gmail.com>

PCI: spacemit-k1: Add Spacemit K3 PCIe host controller support

This commit adds driver support for the PCIe controller on the Spacemit
K3 SoC. It introduces a new device data structure and initialization
callbacks specific to K3 hardware.

> diff --git a/drivers/pci/controller/dwc/pcie-spacemit-k1.c b/drivers/pci/controller/dwc/pcie-spacemit-k1.c
> index ec59ccb710ec1..c3b935f424cd7 100644
> --- a/drivers/pci/controller/dwc/pcie-spacemit-k1.c
> +++ b/drivers/pci/controller/dwc/pcie-spacemit-k1.c

[ ... ]

> +static int k3_pcie_parse_port(struct k1_pcie *k1)
> +{
> +	u32 status0, status1, status2;
> +
> +	/* Clear the status registers */
> +	status0 = readl_relaxed(k1->link + K3_PHY_AHB_IRQSTATUS_INTX);
> +	status1 = readl_relaxed(k1->link + INTR_STATUS);
> +	status2 = readl_relaxed(k1->link + K3_ADDR_INTR_STATUS1);

[Severity: High]
Does this trigger a synchronous external abort or SError during probe?

Looking at k1_pcie_probe(), the driver calls data->parse_port() before
dw_pcie_host_init():

k1_pcie_probe()
  data->parse_port() -> k3_pcie_parse_port()
  ...
  dw_pcie_host_init()
    host_ops->init() -> k3_pcie_init()
      k1_pcie_enable_resources()

The clocks and resets are enabled later in k1_pcie_enable_resources().
Will these early MMIO accesses in k3_pcie_parse_port() crash the kernel
if the bootloader didn't leave the controller clocked and out of reset?

> +
> +	writel_relaxed(status0, k1->link + K3_PHY_AHB_IRQSTATUS_INTX);
> +	writel_relaxed(status1, k1->link + INTR_STATUS);
> +	writel_relaxed(status2, k1->link + K3_ADDR_INTR_STATUS1);
> +
> +	return k1_pcie_parse_port(k1);
> +}

[ ... ]

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Sashiko AI review · https://sashiko.dev/#/patchset/20260923015016.64069-1-inochiama@gmail.com?part=6