Re: [PATCH v8 4/6] PCI: tegra: Add Tegra264 support

Bjorn Helgaas <[email protected]> Wed, 22 Jul 2026 11:44:42 -0500
Newsgroups org.kernel.vger.linux-tegra,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel,org.kernel.vger.linux-pci
Message-ID <20260722164442.GA742885@bhelgaas>
On Thu, Jul 16, 2026 at 07:07:15PM +0200, Thierry Reding wrote:
> From: Thierry Reding <[email protected]>
> 
> Add a driver for the PCIe controller found on NVIDIA Tegra264 SoCs. The
> driver is very small, with its main purpose being to set up the address
> translation registers and then creating a standard PCI host using ECAM.
> ...

> + * The various memory regions used by the controller (I/O, memory, ECAM) are
> + * set up during early boot and have hardware-level protections in place. If
> + * the DT ranges don't match what's been setup, the controller won't be able
> + * to write the address endpoints properly, so make sure to validate that DT
> + * and firmware programming agree on these ranges.
> + */
> +static bool tegra264_pcie_check_ranges(struct platform_device *pdev)

Drive-by comment: I have a bit of an aversion to boolean functions
named "check" because "check" is not a predicate with a true/false or
yes/no answer.

"true" usually means success, which is the opposite of functions that
return 0 for success.

In this case, it looks like "if (tegra264_pcie_check_ranges())" means
the DT ranges match the hardware configuration.  If it were named
"tegra264_pcie_valid_ranges()" or similar, an "if" test like that
would read better.