2014-09-03 11:09 GMT+02:00 Ulf Hansson <ulf.hansson@xxxxxxxxxx>: > On 3 September 2014 11:02, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote: >> On 09/03/2014 11:30 AM, Ulf Hansson wrote: >>> On 2 September 2014 17:49, Jean-Michel Hautbois >>> <jean-michel.hautbois@xxxxxxxxxxx> wrote: >>>> This property is useful when we don't want to access boot partitions on eMMC >>>> >>>> Signed-off-by: Jean-Michel Hautbois <jean-michel.hautbois@xxxxxxxxxxx> >>>> --- >>>> Documentation/devicetree/bindings/mmc/mmc.txt | 1 + >>>> drivers/mmc/host/sdhci-esdhc-imx.c | 8 ++++++++ >>>> include/linux/platform_data/mmc-esdhc-imx.h | 1 + >>>> 3 files changed, 10 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt >>>> index 431716e..59cc854 100644 >>>> --- a/Documentation/devicetree/bindings/mmc/mmc.txt >>>> +++ b/Documentation/devicetree/bindings/mmc/mmc.txt >>>> @@ -40,6 +40,7 @@ Optional properties: >>>> - mmc-hs200-1_2v: eMMC HS200 mode(1.2V I/O) is supported >>>> - mmc-hs400-1_8v: eMMC HS400 mode(1.8V I/O) is supported >>>> - mmc-hs400-1_2v: eMMC HS400 mode(1.2V I/O) is supported >>>> +- no-boot-part : when preset, tells to access boot partitions >>>> >>>> *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line >>>> polarity properties, we have to fix the meaning of the "normal" and "inverted" >>>> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c >>>> index ccec0e3..439e663 100644 >>>> --- a/drivers/mmc/host/sdhci-esdhc-imx.c >>>> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c >>>> @@ -942,6 +942,11 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev, >>>> if (of_property_read_u32(np, "fsl,delay-line", &boarddata->delay_line)) >>>> boarddata->delay_line = 0; >>>> >>>> + if (of_find_property(np, "no-boot-part", NULL)) >>>> + boarddata->access_boot_part = false; >>>> + else >>>> + boarddata->access_boot_part = true; >>>> + >>>> return 0; >>>> } >>>> #else >>>> @@ -1119,6 +1124,9 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) >>>> host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V; >>>> } >>>> >>>> + if (!boarddata->access_boot_part) >>>> + host->mmc->caps2 |= MMC_CAP2_BOOTPART_NOACC; >>>> + >>> >>> Hmm, I don't think MMC_CAP2_BOOTPART_NOACC should have a DT binding. >>> Does it describe the hardware in some form? >>> >>> Actually I would like to question why MMC_CAP2_BOOTPART_NOACC exists >>> at all. If there are cards that don't supports the BOOT area, >>> shouldn't we have a card quirk for it instead of a host cap? Maybe >>> Adrian Hunter, how originally wrote the patch for adding >>> MMC_CAP2_BOOTPART_NOACC, could help me understand the reasons behind >>> it!? >> >> It was added because platform firmware was able to prevent access to the >> boot partitions (for security I think), so attempts to access them would >> fail messily. It was not related to any specific card. > > Adrian, appreciate your clarification. After all it seems like adding > a DT binding for it should be appropriate. > > Kind regards > Uffe Thanks Adrian :). Well, there is boot partitions and rpmb partition, and maybe should we have a binding to prevent access to both of them ? Something else came to my mind, when you want to boot on eMMC, do you need to write u-boot in boot partitions or is it written at the logical adress 0 which is what fdisk uses as start ? Because, if this is not usuable but just scanned I can't see why we bother doing it... ? Thanks, JM -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
