From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 66F1279C0 for ; Wed, 30 Nov 2022 18:50:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7D08C433C1; Wed, 30 Nov 2022 18:50:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669834237; bh=yFqVmtyF1pBSKDJccdOVN1CzDLQTWzm5XEMtqdUhcdA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E7wVUO9E/gJFUH6NWc/ScuNu+bVytawdech2vfd4YU7lMrF3IR9L12L8OzhZYPL6b zcEoNMEnahEs5eUfo4WZmAldTxWXH/+oSw0+NdMqJpJLxC7ebtA1AHiokMmeyf86MH OljdWA+Q3fn5gL8M+3i8wWvk10u+P+2VMt+Rnefw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Linus Walleij , Arnd Bergmann Subject: [PATCH 6.0 180/289] bus: ixp4xx: Dont touch bit 7 on IXP42x Date: Wed, 30 Nov 2022 19:22:45 +0100 Message-Id: <20221130180548.209254973@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221130180544.105550592@linuxfoundation.org> References: <20221130180544.105550592@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Linus Walleij commit ff5a19909b49fe5c0b01ae197f84b741e0f698dc upstream. We face some regressions on a few IXP42x systems when accessing flash, the following unrelated error prints appear from the PCI driver: ixp4xx-pci c0000000.pci: PCI: abort_handler addr = 0xff9ffb5f, isr = 0x0, status = 0x22a0 ixp4xx-pci c0000000.pci: imprecise abort (...) It turns out that while bit 7 is masked "reserved" it is not unused, so masking it off as zero is dangerous, and breaks flash access on some systems such as the NSLU2. Be more careful and avoid masking off any of the reserved bits 7, 8, 9 or 30. Only keep masking EXP_WORD (bit 2) on IXP43x which is necessary in some setups. Fixes: 1c953bda90ca ("bus: ixp4xx: Add a driver for IXP4xx expansion bus") Signed-off-by: Linus Walleij Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20221122134411.2030372-1-linus.walleij@linaro.org Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/bus/intel-ixp4xx-eb.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) --- a/drivers/bus/intel-ixp4xx-eb.c +++ b/drivers/bus/intel-ixp4xx-eb.c @@ -49,7 +49,7 @@ #define IXP4XX_EXP_SIZE_SHIFT 10 #define IXP4XX_EXP_CNFG_0 BIT(9) /* Always zero */ #define IXP43X_EXP_SYNC_INTEL BIT(8) /* Only on IXP43x */ -#define IXP43X_EXP_EXP_CHIP BIT(7) /* Only on IXP43x */ +#define IXP43X_EXP_EXP_CHIP BIT(7) /* Only on IXP43x, dangerous to touch on IXP42x */ #define IXP4XX_EXP_BYTE_RD16 BIT(6) #define IXP4XX_EXP_HRDY_POL BIT(5) /* Only on IXP42x */ #define IXP4XX_EXP_MUX_EN BIT(4) @@ -57,8 +57,6 @@ #define IXP4XX_EXP_WORD BIT(2) /* Always zero */ #define IXP4XX_EXP_WR_EN BIT(1) #define IXP4XX_EXP_BYTE_EN BIT(0) -#define IXP42X_RESERVED (BIT(30)|IXP4XX_EXP_CNFG_0|BIT(8)|BIT(7)|IXP4XX_EXP_WORD) -#define IXP43X_RESERVED (BIT(30)|IXP4XX_EXP_CNFG_0|BIT(5)|IXP4XX_EXP_WORD) #define IXP4XX_EXP_CNFG0 0x20 #define IXP4XX_EXP_CNFG0_MEM_MAP BIT(31) @@ -252,10 +250,9 @@ static void ixp4xx_exp_setup_chipselect( cs_cfg |= val << IXP4XX_EXP_CYC_TYPE_SHIFT; } - if (eb->is_42x) - cs_cfg &= ~IXP42X_RESERVED; if (eb->is_43x) { - cs_cfg &= ~IXP43X_RESERVED; + /* Should always be zero */ + cs_cfg &= ~IXP4XX_EXP_WORD; /* * This bit for Intel strata flash is currently unused, but let's * report it if we find one.