From nobody Thu Oct 2 06:19:46 2025 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79F624A3E for ; Fri, 19 Sep 2025 18:16:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758305797; cv=none; b=VeHtXo3huw0P+Zgi8BmG87Zd1tQ274FGKeZ5fkGI+gKO+XDpfejsmL5EkX/aRzBiHze2MLvooecX3cpxLOxVLLxfZKkdcKtzZ61D/r90Gi8QFheS5ibTABWO7Q2jkf276TBQjjZ+VAQh9qJFF19/CjO+p4GOcMQTMOeSuffcptc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758305797; c=relaxed/simple; bh=svB4c4RUB6k6TMO/taqKy8jJHs6qQsb6dPdPQdI21nk=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=f2skxN56nCVIRQAb6osiyASrq27LwDxSicK/L9Jsg/mUYwZTL1DTgpOtB/QzXcCnbGOhJ01A2t6SitUSEJIU0EnF6/DpwkTlarD6+jMoPmw4lRM8Jm6gvbyaYYvXjslYNtGNpsXSIbxxvP4xC4IX5DC65uxGCzANoDtmz20sOhc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--czapiga.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=YWINuwhM; arc=none smtp.client-ip=209.85.208.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--czapiga.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YWINuwhM" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-62efab531d8so3393851a12.3 for ; Fri, 19 Sep 2025 11:16:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1758305794; x=1758910594; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=5mgMxXZc6JsWSisIXu5YKjlUPOflnR0WNH38+RWcea4=; b=YWINuwhMarzGUvPo57orz93mG954ydMfwx8z+QtZyGmIHnQ3pnjut6lUj/zxPBOuAA QHUQPqnZCiPYEutD9rOksIT5iPsjAYK1kdKOg09DDILVG3tjeAYzq5vqCNpxzleDRObV k93wcGuAKvVvlLVbKhguaeKCnoel2Ef9o/573SmC6vEB+Gtgpf0IOTADt/b7vlSgZzvj PX6EQ3o8OCMrvnPud8QGGXSmOfa/KGOPGoIuudBWhwR7tGZilJHpBwej7xkQQR1sgJHQ veBle8b9A81Qwn+gFR72//4HqBIL0iTHz29oou8gDQpW/FFc/x+67ScMahZQ6LYxwtfg SPKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758305794; x=1758910594; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=5mgMxXZc6JsWSisIXu5YKjlUPOflnR0WNH38+RWcea4=; b=Bz5naI8UwiQIgLrIkW1AHTIJYWv3HE2D2xyYzgBQru2evRYAkGZp/tYILITJoNTo9s fH4LqNWPyV1leWMm4aLf5lCNV/ANzYFsl6pZWyHxKDJz4oLwtO9watFpV0zRsTRGhEw5 e+JPlskK+aThOF2gf+/K7siq+w09hhQYkPofskqflY/+OWMf/cSjaSFrEx8Rl86xxadV Qx1PY2v2s84dULTklBM5aAUp6Ni0U0s318GZ4qgh1+bAc88ixWvUC5lOag/cuFfWnGy9 bEqX9BZpROliqh5riGU8Hb4rNtXjDlq2OZX5EtZ8AfJpfQ4CAH1sJFlDlOkotwCaoveq 9bDg== X-Forwarded-Encrypted: i=1; AJvYcCWk94tQ8HDiEo5CDtKvkzKjHiDFMGEEQuaxW60aQf6dm15p1lpDhABMnd1i7za+ZL1hgVJJAQaga0GP7Lw=@vger.kernel.org X-Gm-Message-State: AOJu0YyFhnxm9kZYTKYO1tMIb53OKNOr5WLtMi24rlwIatKIo1b4ndXg UVcI8Jl9KKK5yE2jlo6RACK8E7vsL4f+2+8Dht34Ac3re5K8YrhYmp5cKPdllTEJFLCVwyFIm2D HeeiXhUwxhQ== X-Google-Smtp-Source: AGHT+IFBF9Kq0n5zsV/eYossWIuj1G3yQkDPq2/13B/MTXPtyGtmb7OfIX4VaMq0zKbRqqvGUOTUkbhU52En X-Received: from edbfi21.prod.google.com ([2002:a05:6402:5515:b0:62f:8b99:d116]) (user=czapiga job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:4586:b0:626:1fce:d2f2 with SMTP id 4fb4d7f45d1cf-62fc0917f14mr3475109a12.16.1758305793785; Fri, 19 Sep 2025 11:16:33 -0700 (PDT) Date: Fri, 19 Sep 2025 18:15:47 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.51.0.534.gc79095c0ca-goog Message-ID: <20250919181547.2172319-1-czapiga@google.com> Subject: [PATCH v2] mtd: spi-nor: core: Check read CR support From: Jakub Czapiga To: Tudor Ambarus Cc: Pratyush Yadav , Michael Walle , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Konrad Adamczyk , Adeel Arshad , Mika Westerberg , Kornel Duleba , Jakub Czapiga Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Some SPI controllers like Intel's one on the PCI bus do not support opcode 35h. This opcode is used to read the Configuration Register on SPI-NOR chips that have 16-bit Status Register configured regardless of the controller support for it. Adding a check call in the setup step allows disabling use of the 35h opcode and falling back to the manual Status Registers management. Before: openat(AT_FDCWD, "/dev/mtd0", O_RDWR) =3D 4 ioctl(4, MIXER_WRITE(6) or MEMUNLOCK, {start=3D0, length=3D0x2000000}) =3D = -1 EOPNOTSUPP After: openat(AT_FDCWD, "/dev/mtd0", O_RDWR) =3D 4 ioctl(4, MIXER_WRITE(6) or MEMUNLOCK, {start=3D0, length=3D0x2000000}) =3D 0 ioctl(4, MIXER_WRITE(5) or MEMLOCK, {start=3D0x1800000, length=3D0x800000})= =3D 0 Suggested-by: Adeel Arshad Signed-off-by: Jakub Czapiga --- Changes since v1: - Use spi_nor_spimem_setup_op instead of spi_nor_read_cr to test opcode - Check only for spi-mem devices - Move check from spi_nor_setup to spi_nor_spimem_adjust_hwcaps drivers/mtd/spi-nor/core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index ac4b960101cc..0c43fcca3d0a 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -2318,6 +2318,16 @@ spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u3= 2 *hwcaps) ¶ms->page_programs[ppidx])) *hwcaps &=3D ~BIT(cap); } + + /* Some SPI controllers might not support CR read opcode. */ + if (!(nor->flags & SNOR_F_NO_READ_CR)) { + struct spi_mem_op op =3D SPI_NOR_RDCR_OP(nor->bouncebuf); + + spi_nor_spimem_setup_op(nor, &op, nor->reg_proto); + + if (spi_nor_spimem_check_op(nor, &op)) + nor->flags |=3D SNOR_F_NO_READ_CR; + } } =20 /** --=20 2.51.0.534.gc79095c0ca-goog