From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 58FB5FF885A for ; Mon, 4 May 2026 17:28:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/+IJ2bHq3KHL+ncW96AkfLa+YxfD/L2ZH5eAWikm96M=; b=vxIJzCTyy0AJr5BMbfS7sakXL3 IYz/12mM7hq1e/TQ/gEUQXJTJv2WejOqqGs5ubNLCSMjGyxwIKEOJM6BHB9EUZoMkDuTrRoWyrtLR KW6Zri49wkweEcgNKKj3xapmNoDE1cX0ZrpICr67EMxUp4Yn78+Z2cLDvkrB/6JJHT96s8n3Wo4pO 0QmNzgo0Y1xPmGh8aikbLMAcbmS0xnx4ryAK6rrGSoBlKs7CLLEhh+onsgxRzKVisWQd9b9MJYPJh uRo81E66mYpq6vB6RIGMjLEu04qbT3vlPkRzzj5xumRGOKXasyVZW4HFQ7FtZ5IstFkdw1GjHDrIZ Ap6RpKYg==; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CM-TRANSID: _____wD3nnnY1vhpZalxDQ--.25765S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxJw1Dtw17Zw1xJFW3Cr4DArb_yoWrCryrpa 9rJa48tF18tFW5ur1jq3Z5Zw1Yg3ZxCrWUKws3Ww17uFsIy3s5KFyFkrySyF97tFZ7uw17 X3W3tF48GF4fAFUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zR58nrUUUUU= X-Originating-IP: [240e:b8f:927e:5900:8c4c:fe90:544d:6d62] X-CM-SenderInfo: rpryjkyvrrlimvzbiqqrwthudrp/xtbC6xqEKGn41toR3gAA3P X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260504_102752_297055_7AFAF64E X-CRM114-Status: GOOD ( 16.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 5/5/26 00:58, Florian Fainelli wrote: > On 5/2/26 04:40, Bjorn Helgaas wrote: >> On Fri, May 01, 2026 at 01:24:38PM -0700, Florian Fainelli wrote: >>> After commit 03f920936977 ("PCI: controller: Validate max-link-speed"), >>> pcie->gen stopped being assigned and as a result the established PCIe >>> link would stop supporting Gen3 speeds on 2712 since pcie->gen is used >>> to populate LnkCntl2 and LnkCap in brcm_pcie_set_gen(). >>> >>> Link: https://github.com/raspberrypi/linux/issues/7343 >>> Reported-by: Dom Cobley >>> Reported-by: Phil Elwell >>> Fixes: 03f920936977 ("PCI: controller: Validate max-link-speed") >>> Signed-off-by: Florian Fainelli >>> --- >>>   drivers/pci/controller/pcie-brcmstb.c | 3 +-- >>>   1 file changed, 1 insertion(+), 2 deletions(-) >>> >>> diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/ >>> controller/pcie-brcmstb.c >>> index 714bcab97b60..6138fc4bc064 100644 >>> --- a/drivers/pci/controller/pcie-brcmstb.c >>> +++ b/drivers/pci/controller/pcie-brcmstb.c >>> @@ -2072,8 +2072,7 @@ static int brcm_pcie_probe(struct >>> platform_device *pdev) >>>           return PTR_ERR(pcie->clk); >>>       ret = of_pci_get_max_link_speed(np); >>> -    if (pcie_get_link_speed(ret) == PCI_SPEED_UNKNOWN) >>> -        pcie->gen = 0; >>> +    pcie->gen = pcie_get_link_speed(ret); >> >> Take a look at https://sashiko.dev/#/patchset/20260501202438.376033-1- >> florian.fainelli%40broadcom.com >> >> The notes at https://github.com/raspberrypi/linux/issues/7343 assumed >> PCI_SPEED_UNKNOWN was 0, but in fact it is 0xff, which means you might >> want the more defensive patch instead. >> >> I'll be happy to replace what's on pci/for-linus if so. > > I am starting to think a revert is the simplest path forward, it's not > clear what pcie_get_link_speed() brings to the table honestly. Hi Florian, The pcie_get_link_speed function is designed to prevent other Root Port drivers from accessing the array pcie_link_speed out of bounds. commit 03f920936977 ("PCI: controller: Validate max-link-speed") diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 062f55690012..714bcab97b60 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -1442,7 +1442,7 @@ static int brcm_pcie_start_link(struct brcm_pcie *pcie) cls = FIELD_GET(PCI_EXP_LNKSTA_CLS, lnksta); nlw = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta); dev_info(dev, "link up, %s x%u %s\n", - pci_speed_string(pcie_link_speed[cls]), nlw, + pci_speed_string(pcie_get_link_speed(cls)), nlw, ssc_good ? "(SSC)" : "(!SSC)"); return 0; @@ -2072,7 +2072,8 @@ static int brcm_pcie_probe(struct platform_device *pdev) return PTR_ERR(pcie->clk); ret = of_pci_get_max_link_speed(np); - pcie->gen = (ret < 0) ? 0 : ret; + if (pcie_get_link_speed(ret) == PCI_SPEED_UNKNOWN) + pcie->gen = 0; Sorry, it's my fault. Should it be changed to the following? Florian, what do you think? diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 714bcab97b60..9a09a48acfb5 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -2074,6 +2074,8 @@ static int brcm_pcie_probe(struct platform_device *pdev) ret = of_pci_get_max_link_speed(np); if (pcie_get_link_speed(ret) == PCI_SPEED_UNKNOWN) pcie->gen = 0; + else + pcie->gen = ret; pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc"); or diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 714bcab97b60..1187e19fbe89 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -2072,8 +2072,7 @@ static int brcm_pcie_probe(struct platform_device *pdev) return PTR_ERR(pcie->clk); ret = of_pci_get_max_link_speed(np); - if (pcie_get_link_speed(ret) == PCI_SPEED_UNKNOWN) - pcie->gen = 0; + pcie->gen = (ret < 0) ? 0 : ret; Best regards, Hans