Re: [PATCH] mmc: omap_hsmmc: Add support for Erratum 2.1.1.128 in device tree boot
From: Balaji T K <hidden>
Date: 2014-02-04 12:44:08
Also in:
linux-arm-kernel, linux-mmc, linux-omap
On Tuesday 21 January 2014 04:59 AM, Nishanth Menon wrote:
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When device is booted using devicetree, platforms impacted by Erratum 2.1.1.128 is not detected easily in the mmc driver. This erratum indicates that the module cannot do multi-block transfers. Handle this by providing a boolean flag to indicate to driver that it is working on a hardware with mentioned limitation. Signed-off-by: Nishanth Menon <nm@ti.com> --- This explains the logs I see: OMAP3430 LDP (ES2.2): uImage only boot: http://slexy.org/raw/s2YrbMAi7c uImage+dtb concatenated boot: http://slexy.org/raw/s20qVg17T0 With the following flag set, device is now able to consistently boot with device tree supported uImage+dtb concat boot. .../devicetree/bindings/mmc/ti-omap-hsmmc.txt | 2 ++ drivers/mmc/host/omap_hsmmc.c | 3 +++ 2 files changed, 5 insertions(+)diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt index 8c8908a..ab36f8b 100644 --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt@@ -26,6 +26,8 @@ specifier is required. dma-names: List of DMA request names. These strings correspond 1:1 with the DMA specifiers listed in dmas. The string naming is to be "rx" and "tx" for RX and TX DMA requests, respectively. +ti,erratum-2.1.1.128: boolean, for OMAP3430/OMAP35xx platforms with broken +multiblock reads
Rather than ti,errata.. specific property, something like caps no/disable multiblock read is more readable in my opinion, Otherwise Acked-by: Balaji T K <redacted>
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Examples:diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 014bfe5..f2d5940 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c@@ -1730,6 +1730,9 @@ static struct omap_mmc_platform_data *of_get_hsmmc_pdata(struct device *dev) if (of_find_property(np, "ti,dual-volt", NULL)) pdata->controller_flags |= OMAP_HSMMC_SUPPORTS_DUAL_VOLT; + if (of_find_property(np, "ti,erratum-2.1.1.128", NULL)) + pdata->controller_flags |= OMAP_HSMMC_BROKEN_MULTIBLOCK_READ; + /* This driver only supports 1 slot */ pdata->nr_slots = 1; pdata->slots[0].switch_pin = cd_gpio;