[PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Jean-Michel Hautbois]

This property is useful when we don't want to access boot partitions on eMMC

Signed-off-by: Jean-Michel Hautbois <jean-michel.hautbois@vodalys.com>
---
 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;
+
	err = sdhci_add_host(host);
	if (err)
		goto disable_clk;
diff --git a/include/linux/platform_data/mmc-esdhc-imx.h b/include/linux/platform_data/mmc-esdhc-imx.h
index 75f70f6..a34ee9e 100644
--- a/include/linux/platform_data/mmc-esdhc-imx.h
+++ b/include/linux/platform_data/mmc-esdhc-imx.h
@@ -46,5 +46,6 @@ struct esdhc_platform_data {
	unsigned int f_max;
	bool support_vsel;
	unsigned int delay_line;
+	bool access_boot_part;
 };
 #endif /* __ASM_ARCH_IMX_ESDHC_H */

2.0.4

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Dong Aisheng]

On Tue, Sep 02, 2014 at 05:49:37PM +0200, Jean-Michel Hautbois wrote:
> This property is useful when we don't want to access boot partitions on eMMC
> 

Any special reason why not access boot partitions on eMMC?
Not allow user to access it?

> Signed-off-by: Jean-Michel Hautbois <jean-michel.hautbois@vodalys.com>
> ---
>  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

The file you changed is common mmc binding doc.
You may also want to add the support in mmc_of_parse.

And since sdhci-esdhc-imx is not using mmc_of_parse currently, maybe it's time
to convert to it.

Regards
Dong Aisheng

> 
>  *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;
> +
> 	err = sdhci_add_host(host);
> 	if (err)
> 		goto disable_clk;
> diff --git a/include/linux/platform_data/mmc-esdhc-imx.h b/include/linux/platform_data/mmc-esdhc-imx.h
> index 75f70f6..a34ee9e 100644
> --- a/include/linux/platform_data/mmc-esdhc-imx.h
> +++ b/include/linux/platform_data/mmc-esdhc-imx.h
> @@ -46,5 +46,6 @@ struct esdhc_platform_data {
> 	unsigned int f_max;
> 	bool support_vsel;
> 	unsigned int delay_line;
> +	bool access_boot_part;
>  };
>  #endif /* __ASM_ARCH_IMX_ESDHC_H */
> 
> 2.0.4
> 

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Ulf Hansson]

On 2 September 2014 17:49, Jean-Michel Hautbois
<jean-michel.hautbois@vodalys.com> 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@vodalys.com>
> ---
>  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!?

Kind regards
Uffe

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Adrian Hunter]

On 09/03/2014 11:30 AM, Ulf Hansson wrote:
> On 2 September 2014 17:49, Jean-Michel Hautbois
> <jean-michel.hautbois@vodalys.com> 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@vodalys.com>
>> ---
>>  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.

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Ulf Hansson]

On 3 September 2014 11:02, Adrian Hunter <adrian.hunter@intel.com> wrote:
> On 09/03/2014 11:30 AM, Ulf Hansson wrote:
>> On 2 September 2014 17:49, Jean-Michel Hautbois
>> <jean-michel.hautbois@vodalys.com> 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@vodalys.com>
>>> ---
>>>  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

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Jean-Michel Hautbois]

2014-09-03 11:09 GMT+02:00 Ulf Hansson <ulf.hansson@linaro.org>:
> On 3 September 2014 11:02, Adrian Hunter <adrian.hunter@intel.com> wrote:
>> On 09/03/2014 11:30 AM, Ulf Hansson wrote:
>>> On 2 September 2014 17:49, Jean-Michel Hautbois
>>> <jean-michel.hautbois@vodalys.com> 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@vodalys.com>
>>>> ---
>>>>  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

Re: [PATCH] mmc: sdhci-esdhc-imx: Enable boot partition access from DT

[Hsin-Hsiang Tseng]

Hi, Jean-Michel
Some platforms which using Samsung exynos SoC, we write u-boot related
bin files in boot partitions(in my case boot partition 1) to boot on
eMMC.
Some platforms which using Qualcomm SoC, written at logical address
0(User Data Area) and they use a-boot not u-boot.
BTW, rpmb partition is not wide use now. As i know, some Intel
platforms have use rpmb partition.

Thanks,
Hsinhsiang

2014-09-03 21:08 GMT+08:00 Jean-Michel Hautbois
<jean-michel.hautbois@vodalys.com>:
> 2014-09-03 11:09 GMT+02:00 Ulf Hansson <ulf.hansson@linaro.org>:
>> On 3 September 2014 11:02, Adrian Hunter <adrian.hunter@intel.com> wrote:
>>> On 09/03/2014 11:30 AM, Ulf Hansson wrote:
>>>> On 2 September 2014 17:49, Jean-Michel Hautbois
>>>> <jean-michel.hautbois@vodalys.com> 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@vodalys.com>
>>>>> ---
>>>>>  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
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