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Mon, 17 Nov 2025 13:47:28 -0800 (PST) Date: Mon, 17 Nov 2025 18:47:22 -0300 From: Geraldo Nascimento To: Shawn Lin , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Bjorn Helgaas , Heiko Stuebner , Krzysztof Kozlowski , Conor Dooley , Johan Jonker , Geraldo Nascimento , Dragan Simic Cc: linux-rockchip@lists.infradead.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH v2 2/4] PCI: rockchip-host: comment danger of 5.0 GT/s speed Message-ID: <2f2825741e189f5d915560eede6ff7bf827546f4.1763415706.git.geraldogabriel@gmail.com> References: Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: According to Rockchip sources, there is grave danger in enabling 5.0 GT/s speed for this core. Add a comment documenting that danger and discouraging end-users from forcing higher speed. Link: https://lore.kernel.org/all/ffd05070-9879-4468-94e3-b88968b4c21b@rock-chips.com/ Cc: stable@vger.kernel.org Reported-by: Dragan Simic Reported-by: Shawn Lin Reviewed-by: Dragan Simic Signed-off-by: Geraldo Nascimento --- drivers/pci/controller/pcie-rockchip-host.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/controller/pcie-rockchip-host.c b/drivers/pci/controller/pcie-rockchip-host.c index ee1822ca01db..0af550277ee5 100644 --- a/drivers/pci/controller/pcie-rockchip-host.c +++ b/drivers/pci/controller/pcie-rockchip-host.c @@ -332,6 +332,9 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip) /* * Enable retrain for gen2. This should be configured only after * gen1 finished. + * + * Dangerous and may lead to catastrophic failure eventually! + * */ status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2); status &= ~PCI_EXP_LNKCTL2_TLS; -- 2.49.0