From nobody Sat Jun 13 19:12:07 2026 Received: from mout01.posteo.de (mout01.posteo.de [185.67.36.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 65F6D3D6CC5 for ; Tue, 5 May 2026 19:36:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.67.36.65 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778009790; cv=none; b=c9OCIgXArEuzc0fvdjtZwCzq9zqgkm69kqs9vG7YlThFzAQtDdn+HOKIYSm2H60ndFr0gMgSgtvAFIDUnF2n5J6XRu79qqZ/uY4UN5usvLggt53O550H4SOBaaP83ccm6/AHLUjwwqenG9BX/2SW0tTFVKQWeUnCti1dUGPHCPk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778009790; c=relaxed/simple; bh=RC874UnZ5V4aNcIf4tUhq3UKLlVDYTm7i6bLqvZPddE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=dV9sWRJ9GcBzFOVb6q3IYjG3oaHDElVEoqeR91WLOPrl0Fk4h+/cgEUsLzZBeJxYH8odh/GugI0HmStm60WfLFRB8gxFVfmGHYTpC+Nq4QMvzb8+tY4UXDdZGik74hlvXWX/W1f74WGAS4tiPN7TNFiBD7PLcRjofkEENW01K+c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.de; spf=pass smtp.mailfrom=posteo.de; dkim=pass (2048-bit key) header.d=posteo.de header.i=@posteo.de header.b=AQAL9Im1; arc=none smtp.client-ip=185.67.36.65 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=posteo.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=posteo.de header.i=@posteo.de header.b="AQAL9Im1" Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id 46BDA240027 for ; Tue, 5 May 2026 21:36:21 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=posteo.de; s=2017; t=1778009781; bh=p2WTjKxAouF+i6RrLI3rv+nCIxExeNhmo7ib34g0WOo=; h=From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:To:Cc:Autocrypt:OpenPGP:From; b=AQAL9Im1qPdj75ZtEbVPZRKGyANGQm+kTiy2C0q0minbdUIPK5iwAA2gvse0MiDQ9 hz0ulDjhtGPjpvOIH6GlNF1CLtnueJE6bOZdTGjvnpkxU9fgatDYfJIWP7nThQWXKt 9nC1lQeKKhaDdeqMu9VZ/wbcuaR5fZhLU2pnk28+q22F0Cf0SNS53RzSuMrkOFAuN7 UTGGPdXQOn9ekSwVw86yp4ZaV3kKtv6TxfizEPn5HaSOjIYXqCDc3h6DlIPIkXs0OW nhIvbCn8R5QHtz5RYmmCafHOfimVtgVFmm5+pj4rWrJqRLADoJILA1CIpvumAAaAsI RU18VbHBYFuyQ== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4g97zm2mtlz9rxM; Tue, 5 May 2026 21:36:20 +0200 (CEST) From: Markus Probst Date: Tue, 05 May 2026 19:36:20 +0000 Subject: [PATCH] ACPI: SPCR: Support UART clock frequency field Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260505-acpi_spcr-v1-1-fd4bc6f4eb53@posteo.de> X-B4-Tracking: v=1; b=H4sIAKNG+mkC/y2NQQqDMBAAvxL23JRkLRb9SpGi66bdghqTKAXx7 01rjwPDzAaRg3CEWm0QeJUo05jBnhTQsx0frKXPDGiwNJfC6Ja83KOnoEtbGXR9hYVDyL4P7OT 9a92ag+PSvZjSN/A3As9LnqRDg66NrGkaBkm1Wq9nqwMhNPv+Ae08xg6ZAAAA X-Change-ID: 20260430-acpi_spcr-61902fd923f2 To: "Rafael J. Wysocki" , Len Brown Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Markus Probst X-Developer-Signature: v=1; a=openpgp-sha256; l=1254; i=markus.probst@posteo.de; h=from:subject:message-id; bh=RC874UnZ5V4aNcIf4tUhq3UKLlVDYTm7i6bLqvZPddE=; b=owEBiQJ2/ZANAwAIATR2H/jnrUPSAcsmYgBp+ka0WlBJvrebw1KoVroofR+RdU8bZ/GtTte77 5Z0VRU8yP+JAk8EAAEIADkWIQSCdBjE9KxY53IwxHM0dh/4561D0gUCafpGtBsUgAAAAAAEAA5t YW51MiwyLjUrMS4xMiwyLDIACgkQNHYf+OetQ9Jh2Q//dhCAKoy0tiZOAasNEXXod5fxk3UpAmj LOhW+y9izN/dZgBnFhsf9Lpf30iCICOq8lfWzM6uCbY51G8lBOKfVH2fnqR2IJ4cir42sYoFSc+ ppNYAG78cd4vgwWIKm99tfAZ8hu/y78os1TpKpkRAkaMp8j/ev9cavQ2kWA7HHstJfg7XlitDA3 natbndoxk2rkx+Hyb5vdNszVWTdMlPGT5STU9bjqx6W5qzoRR8RFCpSL0ng4cHEk7QL/iTlQksF oVWamA3AOTwXlKX6NT+HWd/da+x/TohiFzAZ/Rue3qZBiUVXBeyaD7MMLFnoGFFCOzRwEDV08Uz y1z/tONblCPVvsOaQxO0OsNrcfJUkvnJzaUf33XgeTO7+9/x6ypuZvXL5npSe4GD785ESqZA9cW 8ReW0y+Jw2Cstfa98tggzszjFsMUN8TpkDIt1QJNEnnGhbmC1Y9PKp7KT5jrgR8q6JiresBw3Jf Upmomrque5x45QWBqCMpzUZD6TdCPJxCcqHbuk7/wV2Qcl+NfRXCIW1P4AukSgQzpP3bALR1Xxw FKCO5T+HgWrmfVKXH1Xb6x0qGV19r2jCZLAPSxZtKw5c4f7em0PxRd98ByBEpsNM/jOM+eJtjV3 l498RfRqAqb650D9FtlfS6NkmN0qkqsBQbT48PNUEyMq2jRBrFxU= X-Developer-Key: i=markus.probst@posteo.de; a=openpgp; fpr=827418C4F4AC58E77230C47334761FF8E7AD43D2 Autocrypt: addr=markus.probst@posteo.de; prefer-encrypt=mutual; keydata=xsFNBGiDvXgBEADAXUceKafpl46S35UmDh2wRvvx+UfZbcTjeQOlSwKP7YVJ4JOZrVs93qReNLkO WguIqPBxR9blQ4nyYrqSCV+MMw/3ifyXIm6Pw2YRUDg+WTEOjTixRCoWDgUj1nOsvJ9tVAm76Ww+ /pAnepVRafMID0rqEfD9oGv1YrfpeFJhyE2zUw3SyyNLIKWD6QeLRhKQRbSnsXhGLFBXCqt9k5JA RhgQof9zvztcCVlT5KVvuyfC4H+HzeGmu9201BVyihJwKdcKPq+n/aY5FUVxNTgtI9f8wIbmfAja oT1pjXSp+dszakA98fhONM98pOq723o/1ZGMZukyXFfsDGtA3BB79HoopHKujLGWAGskzClwTjRQ xBqxh/U/lL1pc+0xPWikTNCmtziCOvv0KA0arDOMQlyFvImzX6oGVgE4ksKQYbMZ3Ikw6L1Rv1J+ FvN0aNwOKgL2ztBRYscUGcQvA0Zo1fGCAn/BLEJvQYShWKeKqjyncVGoXFsz2AcuFKe1pwETSsN6 OZncjy32e4ktgs07cWBfx0v62b8md36jau+B6RVnnodaA8++oXl3FRwiEW8XfXWIjy4umIv93tb8 8ekYsfOfWkTSewZYXGoqe4RtK80ulMHb/dh2FZQIFyRdN4HOmB4FYO5sEYFr9YjHLmDkrUgNodJC XCeMe4BO4iaxUQARAQABzRdtYXJrdXMucHJvYnN0QHBvc3Rlby5kZcLBkQQTAQgAOxYhBIJ0GMT0 rFjncjDEczR2H/jnrUPSBQJog714AhsDBQsJCAcCAiICBhUKCQgLAgQWAgMBAh4HAheAAAoJEDR2 H/jnrUPSgdkQAISaTk2D345ehXEkn5z2yUEjaVjHIE7ziqRaOgn/QanCgeTUinIv6L6QXUFvvIfH 1OLPwQ1hfvEg9NnNLyFezWSy6jvoVBTIPqicD/r3FkithnQ1IDkdSjrarPMxJkvuh3l7XZHo49GV HQ8i5zh5w4YISrcEtE99lJisvni2Jqx7we5tey9voQFDyM8jxlSWv3pmoUTCtBkX/eKHJXosgsuS B4TGDCVPOjla/emI5c9MhMG7O4WEEmoSdPbmraPw66YZD6uLyhV4DPHbiDWRzXWnClHSyjB9rky9 lausFxogvu4l9H+KDsXIadNDWdLdu1/enS/wDd9zh5S78rY2jeXaG4mnf4seEKamZ7KQ6FIHrcyP ezdDzssPQcTQcGRMQzCn6wP3tlGk7rsfmyHMlFqdRoNNv+ZER/OkmZFPW655zRfbMi0vtrqK2Awm 9ggobb1oktfd9PPNXMUY+DNVlgR2G7jLnenSoQausLUm0pHoNE8TWFv851Y6SOYnvn488sP1Tki5 F3rKwclawQFHUXTCQw+QSh9ay8xgnNZfH+u9NY7w3gPoeKBOAFcBc2BtzcgekeWS8qgEmm2/oNFV G0ivPQbRx8FjRKbuF7g3YhgNZZ0ac8FneuUtJ2PkSIFTZhaAiC0utvxk0ndmWFiW4acEkMZGrLaM L2zWNjrqwsD2zsFNBGiDvXgBEADCXQy1n7wjRxG12DOVADawjghKcG+5LtEf31WftHKLFbp/HArj BhkT6mj+CCI1ClqY+FYU5CK/s0ScMfLxRGLZ0Ktzawb78vOgBVFT3yB1yWBTewsAXdqNqRooaUNo 8cG/NNJLjhccH/7PO/FWX5qftOVUJ/AIsAhKQJ18Tc8Ik73v427EDxuKb9mTAnYQFA3Ev3hAiVbO 6Rv39amVOfJ8sqwiSUGidj2Fctg2aB5JbeMln0KCUbTD1LhEFepeKypfofAXQbGwaCjAhmkWy/q3 IT1mUrPxOngbxdRoOx1tGUC0HCMUW1sFaJgQPMmDcR0JGPOpgsKnitsSnN7ShcCr1buel7vLnUMD +TAZ5opdoF6HjAvAnBQaijtK6minkrM0seNXnCg0KkV8xhMNa6zCs1rq4GgjNLJue2EmuyHooHA4 7JMoLVHcxVeuNTp6K2+XRx0Pk4e2Lj8IVy9yEYyrywEOC5XRW37KJjsiOAsumi1rkvM7QREWgUDe Xs0+RpxI3QrrANh71fLMRo7LKRF3Gvw13NVCCC9ea20P4PwhgWKStkwO2NO+YJsAoS1QycMi/vKu 0EHhknYXamaSV50oZzHKmX56vEeJHTcngrM8R1SwJCYopCx9gkz90bTVYlitJa5hloWTYeMD7FNj Y6jfVSzgM/K4gMgUNDW/PPGeMwARAQABwsF2BBgBCAAgFiEEgnQYxPSsWOdyMMRzNHYf+OetQ9IF AmiDvXgCGwwACgkQNHYf+OetQ9LHDBAAhk+ab8+WrbS/b1/gYW3q1KDiXU719nCtfkUVXKidW5Ec Idlr5HGt8ilLoxSWT2Zi368iHCXS0WenGgPwlv8ifvB7TOZiiTDZROZkXjEBmU4nYjJ7GymawpWv oQwjMsPuq6ysbzWtOZ7eILx7cI0FjQeJ/Q2baRJub0uAZNwBOxCkAS6lpk5Fntd2u8CWmDQo4SYp xeuQ+pwkp0yEP30RhN2BO2DXiBEGSZSYh+ioGbCHQPIV3iVj0h6lcCPOqopZqyeCfigeacBI0nvN jHWz/spzF3+4OS+3RJvoHtAQmProxyGib8iVsTxgZO3UUi4TSODeEt0i0kHSPY4sCciOyXfAyYoD DFqhRjOEwBBxhr+scU4C1T2AflozvDwq3VSONjrKJUkhd8+WsdXxMdPFgBQuiKKwUy11mz6KQfcR wmDehF3UaUoxa+YIhWPbKmycxuX/D8SvnqavzAeAL1OcRbEI/HsoroVlEFbBRNBZLJUlnTPs8ZcU 4+8rq5YX1GUrJL3jf6SAfSgO7UdkEET3PdcKFYtS+ruV1Cp5V0q4kCfI5jk25iiz8grM2wOzVSsc l1mEkhiEPH87HP0whhb544iioSnumd3HJKL7dzhRegsMizatupp8D65A2JziW0WKopa1iw9fti3A aBeNN4ijKZchBXHPgVx+YtWRHfcm4l8= OpenPGP: url=https://posteo.de/keys/markus.probst@posteo.de.asc; preference=encrypt The Microsoft Serial Port Console Redirection (SPCR) specification revision 1.08 comprises additional field: UART Clock Frequency [1]. It contains a non-zero value indicating the UART clock frequency in Hz. Link: https://learn.microsoft.com/en-us/windows-hardware/drivers/serports/s= erial-port-console-redirection-table [1] Signed-off-by: Markus Probst --- drivers/acpi/spcr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c index 73cb933fdc89..d80ad87efae0 100644 --- a/drivers/acpi/spcr.c +++ b/drivers/acpi/spcr.c @@ -220,6 +220,9 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool e= nable_console) if (!baud_rate) { snprintf(opts, sizeof(opts), "%s,%s,0x%llx", uart, iotype, table->serial_port.address); + } else if (table->header.revision >=3D 3 && table->uart_clk_freq) { + snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d,%u", uart, iotype, + table->serial_port.address, baud_rate, table->uart_clk_freq); } else { snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d", uart, iotype, table->serial_port.address, baud_rate); --- base-commit: 9e0898f1c0f134c6bad146ca8578f73c3e40ac0a change-id: 20260430-acpi_spcr-61902fd923f2