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 EF4B417DA3A; Wed, 3 Jul 2024 11:12:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720005144; cv=none; b=aWi/RtoxXAZsq3kocFPvxzi8Zq84eQT9v+gLXX1EcU2g/OA0pPSSvwz3J4QB7JVOERGfYVj2VH3B4X/B+atiSYmPgv+36vu5CjBXA6PLhoiMTv7Fp+ieKzjsp5jqM1sgVHTc2CgvPXfZ281abvzTL7AuO34YRM9bLV6scF9FP7s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720005144; c=relaxed/simple; bh=4eNpIL0iCS6CjnaVPXMpuWY0eUHwHm0VtIZ00tgsRNU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=T0Te1i1DB51cZs49FqdgeKVQP1/LCENGjQeV9qTOzB7arNdh2e4/bGHjsPMl/eCRkTXMSZvuGWINP3Mktt82zoqlLi6VZCTQmTq5EM4ApWDpaluRJr2PczWL5ReI1I+n1nkughnazhrLLrq2bNWy11A5MFsDEJdWrU9XMeDFiRE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UrfSHPSX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="UrfSHPSX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77CF7C2BD10; Wed, 3 Jul 2024 11:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1720005143; bh=4eNpIL0iCS6CjnaVPXMpuWY0eUHwHm0VtIZ00tgsRNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UrfSHPSXVJniTm+TSmAJDVBirhXjxyvjn+nE788qg8wRf8lvJNjcPEQY8iSNG0/Un /nNlpDDbVAAws/u3IktS5wdMGKAjM7I1chX5GpIP8NJQYx5KfR7lQxhw7003oqNrDy oCwQHbKFP2kWn19Iigz8LRwHAFJhhCxPZdD9Epo4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Udit Kumar Subject: [PATCH 5.10 258/290] serial: 8250_omap: Implementation of Errata i2310 Date: Wed, 3 Jul 2024 12:40:39 +0200 Message-ID: <20240703102913.891232751@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240703102904.170852981@linuxfoundation.org> References: <20240703102904.170852981@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Udit Kumar commit 9d141c1e615795eeb93cd35501ad144ee997a826 upstream. As per Errata i2310[0], Erroneous timeout can be triggered, if this Erroneous interrupt is not cleared then it may leads to storm of interrupts, therefore apply Errata i2310 solution. [0] https://www.ti.com/lit/pdf/sprz536 page 23 Fixes: b67e830d38fa ("serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs") Cc: stable@vger.kernel.org Signed-off-by: Udit Kumar Link: https://lore.kernel.org/r/20240619105903.165434-1-u-kumar1@ti.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_omap.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -164,6 +164,10 @@ static void uart_write(struct omap8250_p writel(val, priv->membase + (reg << OMAP_UART_REGSHIFT)); } +/* Timeout low and High */ +#define UART_OMAP_TO_L 0x26 +#define UART_OMAP_TO_H 0x27 + /* * Called on runtime PM resume path from omap8250_restore_regs(), and * omap8250_set_mctrl(). @@ -647,13 +651,24 @@ static irqreturn_t omap8250_irq(int irq, /* * On K3 SoCs, it is observed that RX TIMEOUT is signalled after - * FIFO has been drained, in which case a dummy read of RX FIFO - * is required to clear RX TIMEOUT condition. + * FIFO has been drained or erroneously. + * So apply solution of Errata i2310 as mentioned in + * https://www.ti.com/lit/pdf/sprz536 */ if (priv->habit & UART_RX_TIMEOUT_QUIRK && - (iir & UART_IIR_RX_TIMEOUT) == UART_IIR_RX_TIMEOUT && - serial_port_in(port, UART_OMAP_RX_LVL) == 0) { - serial_port_in(port, UART_RX); + (iir & UART_IIR_RX_TIMEOUT) == UART_IIR_RX_TIMEOUT) { + unsigned char efr2, timeout_h, timeout_l; + + efr2 = serial_in(up, UART_OMAP_EFR2); + timeout_h = serial_in(up, UART_OMAP_TO_H); + timeout_l = serial_in(up, UART_OMAP_TO_L); + serial_out(up, UART_OMAP_TO_H, 0xFF); + serial_out(up, UART_OMAP_TO_L, 0xFF); + serial_out(up, UART_OMAP_EFR2, UART_OMAP_EFR2_TIMEOUT_BEHAVE); + serial_in(up, UART_IIR); + serial_out(up, UART_OMAP_EFR2, efr2); + serial_out(up, UART_OMAP_TO_H, timeout_h); + serial_out(up, UART_OMAP_TO_L, timeout_l); } /* Stop processing interrupts on input overrun */