From mboxrd@z Thu Jan 1 00:00:00 1970 From: Radu Pirea Subject: [RFC PATCH 1/2] Revert "spi: atmel: fix corrupted data issue on SAM9 family SoCs" Date: Wed, 15 Nov 2017 18:35:31 +0200 Message-ID: <1510763732-10151-2-git-send-email-radu.pirea@microchip.com> References: <1510763732-10151-1-git-send-email-radu.pirea@microchip.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Radu Pirea To: , , , Return-path: In-Reply-To: <1510763732-10151-1-git-send-email-radu.pirea-UWL1GkI3JZL3oGB3hsPCZA@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: This reverts commit 7094576ccdc3acfe1e06a1e2ab547add375baf7f. A better fix was found and DMA for SAM9 SoCs must be enabled. Signed-off-by: Radu Pirea --- drivers/spi/spi-atmel.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index f95da36..4e5e51f 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -269,7 +269,6 @@ struct atmel_spi_caps { bool is_spi2; bool has_wdrbt; bool has_dma_support; - bool has_pdc_support; }; /* @@ -1426,28 +1425,7 @@ static void atmel_get_caps(struct atmel_spi *as) as->caps.is_spi2 = version > 0x121; as->caps.has_wdrbt = version >= 0x210; -#ifdef CONFIG_SOC_SAM_V4_V5 - /* - * Atmel SoCs based on ARM9 (SAM9x) cores should not use spi_map_buf() - * since this later function tries to map buffers with dma_map_sg() - * even if they have not been allocated inside DMA-safe areas. - * On SoCs based on Cortex A5 (SAMA5Dx), it works anyway because for - * those ARM cores, the data cache follows the PIPT model. - * Also the L2 cache controller of SAMA5D2 uses the PIPT model too. - * In case of PIPT caches, there cannot be cache aliases. - * However on ARM9 cores, the data cache follows the VIVT model, hence - * the cache aliases issue can occur when buffers are allocated from - * DMA-unsafe areas, by vmalloc() for instance, where cache coherency is - * not taken into account or at least not handled completely (cache - * lines of aliases are not invalidated). - * This is not a theorical issue: it was reproduced when trying to mount - * a UBI file-system on a at91sam9g35ek board. - */ - as->caps.has_dma_support = false; -#else as->caps.has_dma_support = version >= 0x212; -#endif - as->caps.has_pdc_support = version < 0x212; } /*-------------------------------------------------------------------------*/ @@ -1588,7 +1566,7 @@ static int atmel_spi_probe(struct platform_device *pdev) } else if (ret == -EPROBE_DEFER) { return ret; } - } else if (as->caps.has_pdc_support) { + } else { as->use_pdc = true; } -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html