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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03C84C001B0 for ; Sun, 16 Jul 2023 20:26:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231975AbjGPU0E (ORCPT ); Sun, 16 Jul 2023 16:26:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48186 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231972AbjGPU0D (ORCPT ); Sun, 16 Jul 2023 16:26:03 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00FD9BC for ; Sun, 16 Jul 2023 13:26:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 94BDF60EB0 for ; Sun, 16 Jul 2023 20:26:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6163C433C8; Sun, 16 Jul 2023 20:26:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689539162; bh=2s7RTo3VNv6TmVXLN6GEj8GSY4RWSlqZJQSydBtaFVk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=On6TZLxpjbeRR9/9SAlkj1abcrQubWm8NWACC60uqVkVRjq0lPefdjZY99nu86FYf XC4qbUZUecMbgv39vjCHJlEHVxevw27Pp5KjTX9cOfqHzwxrZE0OCVxl+REkLLgP3u aOKfhDdz1AMG33Z4g6AuBSA7Ux8QSgUII9ArAaEw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Artur Rojek , Geert Uytterhoeven , John Paul Adrian Glaubitz , Sasha Levin Subject: [PATCH 6.4 709/800] sh: dma: Fix DMA channel offset calculation Date: Sun, 16 Jul 2023 21:49:22 +0200 Message-ID: <20230716195005.587854831@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230716194949.099592437@linuxfoundation.org> References: <20230716194949.099592437@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Artur Rojek [ Upstream commit e82e47584847129a20b8c9f4a1dcde09374fb0e0 ] Various SoCs of the SH3, SH4 and SH4A family, which use this driver, feature a differing number of DMA channels, which can be distributed between up to two DMAC modules. The existing implementation fails to correctly accommodate for all those variations, resulting in wrong channel offset calculations and leading to kernel panics. Rewrite dma_base_addr() in order to properly calculate channel offsets in a DMAC module. Fix dmaor_read_reg() and dmaor_write_reg(), so that the correct DMAC module base is selected for the DMAOR register. Fixes: 7f47c7189b3e8f19 ("sh: dma: More legacy cpu dma chainsawing.") Signed-off-by: Artur Rojek Reviewed-by: Geert Uytterhoeven Reviewed-by: John Paul Adrian Glaubitz Link: https://lore.kernel.org/r/20230527164452.64797-2-contact@artur-rojek.eu Signed-off-by: John Paul Adrian Glaubitz Signed-off-by: Sasha Levin --- arch/sh/drivers/dma/dma-sh.c | 37 +++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/arch/sh/drivers/dma/dma-sh.c b/arch/sh/drivers/dma/dma-sh.c index 96c626c2cd0a4..306fba1564e5e 100644 --- a/arch/sh/drivers/dma/dma-sh.c +++ b/arch/sh/drivers/dma/dma-sh.c @@ -18,6 +18,18 @@ #include #include +/* + * Some of the SoCs feature two DMAC modules. In such a case, the channels are + * distributed equally among them. + */ +#ifdef SH_DMAC_BASE1 +#define SH_DMAC_NR_MD_CH (CONFIG_NR_ONCHIP_DMA_CHANNELS / 2) +#else +#define SH_DMAC_NR_MD_CH CONFIG_NR_ONCHIP_DMA_CHANNELS +#endif + +#define SH_DMAC_CH_SZ 0x10 + /* * Define the default configuration for dual address memory-memory transfer. * The 0x400 value represents auto-request, external->external. @@ -29,7 +41,7 @@ static unsigned long dma_find_base(unsigned int chan) unsigned long base = SH_DMAC_BASE0; #ifdef SH_DMAC_BASE1 - if (chan >= 6) + if (chan >= SH_DMAC_NR_MD_CH) base = SH_DMAC_BASE1; #endif @@ -40,13 +52,13 @@ static unsigned long dma_base_addr(unsigned int chan) { unsigned long base = dma_find_base(chan); - /* Normalize offset calculation */ - if (chan >= 9) - chan -= 6; - if (chan >= 4) - base += 0x10; + chan = (chan % SH_DMAC_NR_MD_CH) * SH_DMAC_CH_SZ; + + /* DMAOR is placed inside the channel register space. Step over it. */ + if (chan >= DMAOR) + base += SH_DMAC_CH_SZ; - return base + (chan * 0x10); + return base + chan; } #ifdef CONFIG_SH_DMA_IRQ_MULTI @@ -250,12 +262,11 @@ static int sh_dmac_get_dma_residue(struct dma_channel *chan) #define NR_DMAOR 1 #endif -/* - * DMAOR bases are broken out amongst channel groups. DMAOR0 manages - * channels 0 - 5, DMAOR1 6 - 11 (optional). - */ -#define dmaor_read_reg(n) __raw_readw(dma_find_base((n)*6)) -#define dmaor_write_reg(n, data) __raw_writew(data, dma_find_base(n)*6) +#define dmaor_read_reg(n) __raw_readw(dma_find_base((n) * \ + SH_DMAC_NR_MD_CH) + DMAOR) +#define dmaor_write_reg(n, data) __raw_writew(data, \ + dma_find_base((n) * \ + SH_DMAC_NR_MD_CH) + DMAOR) static inline int dmaor_reset(int no) { -- 2.39.2