Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-10 Thread maitysanchayan
Hello Stefan,

On 15-07-08 22:55:23, Stefan Wahren wrote:
> Hi Sanchayan,
> 
> > maitysancha...@gmail.com hat am 8. Juli 2015 um 07:39 geschrieben:
> >
> >
> > [...]
> > > > >
> > > > > Looking at valid_fuse_addr shows me 0x3F as last valid register. So 
> > > > > the
> > > > > rest
> > > > > of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw 
> > > > > access
> > > > > could be
> > > > > uninitializied.
> > > >
> > > > Sorry I did not exactly get you here. The intention behind using the
> > > > valid_fuse_addr
> > > > is to allow reading only from valid fuse addresses and avoid reading 
> > > > from
> > > > all
> > > > other
> > > > locations as per the Fuse map address table 35-1.
> > >
> > > Yes, i got your intention. But from my unterstand the read function should
> > > fill
> > > up
> > > the complete buffer with defined values. My MXS OCOTP driver have the same
> > > problem
> > > and fill up the invalid registers with zero.
> >
> > I must admit I had not thought of that. Thats a valid point. I dont know at
> > the
> > moment however what would be the correct approach here. Perhaps filling
> > locations
> > other than the valid fuse addresses as per the fuse map table with 
> > 0xBADABADA
> > is
> > the right thing? Anyways that's what is going to be returned if we were to
> > read
> > a location which is read locked or reserved.
> 
> since we are operating in userspace the behavior shouldn't be specific to the
> device.
> It would be good when all drivers behave the same. But i think it would be 
> much
> better
> as the nvmem framework take care of it and preinit the buffer with a defined
> value.

There is a v7 now. Yet to give that a try or look at it.

> 
> >
> > However since the fuse address and base address mapping is not exactly 
> > linear,
> > this would require some additional logic than the simple thing I did. 
> 
> I defined a regmap_access_table for valid read registers in my case. But i 
> think
> in your case
> an implementation of the readable_reg callback in the regmap_config would be
> more elegant.
> 
> You can validate your implementation under /sys/kernel/debug/regmap/

Thank you for the input. I will have a look at it and give it a try.

> 
> Sorry, i'm a newbie to regmap.

Same here as well :)

Regards,
Sanchayan.
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-10 Thread maitysanchayan
Hello Stefan,

On 15-07-08 22:55:23, Stefan Wahren wrote:
 Hi Sanchayan,
 
  maitysancha...@gmail.com hat am 8. Juli 2015 um 07:39 geschrieben:
 
 
  [...]

 Looking at valid_fuse_addr shows me 0x3F as last valid register. So 
 the
 rest
 of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw 
 access
 could be
 uninitializied.
   
Sorry I did not exactly get you here. The intention behind using the
valid_fuse_addr
is to allow reading only from valid fuse addresses and avoid reading 
from
all
other
locations as per the Fuse map address table 35-1.
  
   Yes, i got your intention. But from my unterstand the read function should
   fill
   up
   the complete buffer with defined values. My MXS OCOTP driver have the same
   problem
   and fill up the invalid registers with zero.
 
  I must admit I had not thought of that. Thats a valid point. I dont know at
  the
  moment however what would be the correct approach here. Perhaps filling
  locations
  other than the valid fuse addresses as per the fuse map table with 
  0xBADABADA
  is
  the right thing? Anyways that's what is going to be returned if we were to
  read
  a location which is read locked or reserved.
 
 since we are operating in userspace the behavior shouldn't be specific to the
 device.
 It would be good when all drivers behave the same. But i think it would be 
 much
 better
 as the nvmem framework take care of it and preinit the buffer with a defined
 value.

There is a v7 now. Yet to give that a try or look at it.

 
 
  However since the fuse address and base address mapping is not exactly 
  linear,
  this would require some additional logic than the simple thing I did. 
 
 I defined a regmap_access_table for valid read registers in my case. But i 
 think
 in your case
 an implementation of the readable_reg callback in the regmap_config would be
 more elegant.
 
 You can validate your implementation under /sys/kernel/debug/regmap/

Thank you for the input. I will have a look at it and give it a try.

 
 Sorry, i'm a newbie to regmap.

Same here as well :)

Regards,
Sanchayan.
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-08 Thread Stefan Wahren
Hi Sanchayan,

> maitysancha...@gmail.com hat am 8. Juli 2015 um 07:39 geschrieben:
>
>
> [...]
> > > >
> > > > Looking at valid_fuse_addr shows me 0x3F as last valid register. So the
> > > > rest
> > > > of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw access
> > > > could be
> > > > uninitializied.
> > >
> > > Sorry I did not exactly get you here. The intention behind using the
> > > valid_fuse_addr
> > > is to allow reading only from valid fuse addresses and avoid reading from
> > > all
> > > other
> > > locations as per the Fuse map address table 35-1.
> >
> > Yes, i got your intention. But from my unterstand the read function should
> > fill
> > up
> > the complete buffer with defined values. My MXS OCOTP driver have the same
> > problem
> > and fill up the invalid registers with zero.
>
> I must admit I had not thought of that. Thats a valid point. I dont know at
> the
> moment however what would be the correct approach here. Perhaps filling
> locations
> other than the valid fuse addresses as per the fuse map table with 0xBADABADA
> is
> the right thing? Anyways that's what is going to be returned if we were to
> read
> a location which is read locked or reserved.

since we are operating in userspace the behavior shouldn't be specific to the
device.
It would be good when all drivers behave the same. But i think it would be much
better
as the nvmem framework take care of it and preinit the buffer with a defined
value.

>
> However since the fuse address and base address mapping is not exactly linear,
> this would require some additional logic than the simple thing I did. 

I defined a regmap_access_table for valid read registers in my case. But i think
in your case
an implementation of the readable_reg callback in the regmap_config would be
more elegant.

You can validate your implementation under /sys/kernel/debug/regmap/

Sorry, i'm a newbie to regmap.

Stefan

> Also OCOTP requires the fuse address to be written. May be using the nvmem
> consumer DT property
> gets something?! Not sure atm.
>
> - Sanchayan.
>
> ___
> linux-arm-kernel mailing list
> linux-arm-ker...@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-08 Thread Stefan Wahren
Hi Sanchayan,

 maitysancha...@gmail.com hat am 8. Juli 2015 um 07:39 geschrieben:


 [...]
   
Looking at valid_fuse_addr shows me 0x3F as last valid register. So the
rest
of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw access
could be
uninitializied.
  
   Sorry I did not exactly get you here. The intention behind using the
   valid_fuse_addr
   is to allow reading only from valid fuse addresses and avoid reading from
   all
   other
   locations as per the Fuse map address table 35-1.
 
  Yes, i got your intention. But from my unterstand the read function should
  fill
  up
  the complete buffer with defined values. My MXS OCOTP driver have the same
  problem
  and fill up the invalid registers with zero.

 I must admit I had not thought of that. Thats a valid point. I dont know at
 the
 moment however what would be the correct approach here. Perhaps filling
 locations
 other than the valid fuse addresses as per the fuse map table with 0xBADABADA
 is
 the right thing? Anyways that's what is going to be returned if we were to
 read
 a location which is read locked or reserved.

since we are operating in userspace the behavior shouldn't be specific to the
device.
It would be good when all drivers behave the same. But i think it would be much
better
as the nvmem framework take care of it and preinit the buffer with a defined
value.


 However since the fuse address and base address mapping is not exactly linear,
 this would require some additional logic than the simple thing I did. 

I defined a regmap_access_table for valid read registers in my case. But i think
in your case
an implementation of the readable_reg callback in the regmap_config would be
more elegant.

You can validate your implementation under /sys/kernel/debug/regmap/

Sorry, i'm a newbie to regmap.

Stefan

 Also OCOTP requires the fuse address to be written. May be using the nvmem
 consumer DT property
 gets something?! Not sure atm.

 - Sanchayan.

 ___
 linux-arm-kernel mailing list
 linux-arm-ker...@lists.infradead.org
 http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-07 Thread maitysanchayan
Hi Stefan,

On 15-07-07 14:49:06, Stefan Wahren wrote:
> Hi Sanchayan,
> 
> > maitysancha...@gmail.com hat am 7. Juli 2015 um 07:19 geschrieben:
> >
> >
> > [...]
> > > > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> > > > index 17f1a57..84c830d 100644
> > > > --- a/drivers/nvmem/Kconfig
> > > > +++ b/drivers/nvmem/Kconfig
> > > > @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
> > > > This driver can also be built as a module. If so, the module
> > > > will be called eeprom-sunxi-sid.
> > > >
> > > > +config NVMEM_VF610_OCOTP
> > > > + tristate "VF610 SoCs OCOTP support"
> > > > + depends on SOC_VF610
> > > > + help
> > > > + This is a driver for the 'OCOTP' available on various Vybrid
> > > > + devices.
> > >
> > > I don't know much about Vybrid. But this driver is specific for VF610, 
> > > isn't
> > > it?
> >
> > Sorry. I only checked on VF50 and VF61. Will check if is it available with 
> > the
> > other Vybrid devices and change if it is not so.
> 
> no problem. If you spend time in testing your driver with different devices, 
> you
> could mention
> this in your patch description. The naming VF610 suggests that the driver is
> very specific.
> That confuses me a little bit.

Sorry about that. Will add the necessary information in the next respin for 
sure.

> 
> >
> > >
> > > > +
> > > > +
> > > > +static int vf610_ocotp_write(void *context, const void *data, size_t
> > > > count)
> > > > +{
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int vf610_ocotp_read(void *context,
> > > > + const void *offset, size_t reg_size,
> > > > + void *val, size_t val_size)
> > > > +{
> > > > + void __iomem *ocotp_base = context;
> > > > + u32 *buf = val;
> > > > + u32 reg;
> > > > + int ret;
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < ARRAY_SIZE(valid_fuse_addr); i++) {
> > > > + vf610_ocotp_set_timing(ocotp_base, ocotp_timing);
> > > > + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
> > > > + if (ret)
> > > > + return ret;
> > >
> > > Is it really necessary to set the timing in the loop, instead before?
> >
> > I will test it once. From my understanding of 35.3.1.5 I thought the timing
> > needs to explicitly programmed on every read. Perhaps I took it too 
> > literally.
> 
> It was only a question. If barebox does the same, it should be okay.
>

Yes, the code logic is completely similar to barebox except for changes like
how timeout is handled here in the wait busy function.

> >
> > >
> > > > +
> > > > + reg = readl(ocotp_base + OCOTP_CTRL_REG);
> > > > + reg &= ~OCOTP_CTRL_ADDR_MASK;
> > > > + reg &= ~OCOTP_CTRL_WR_UNLOCK_MASK;
> > > > + reg |= BF(valid_fuse_addr[i], OCOTP_CTRL_ADDR);
> > > > + writel(reg, ocotp_base + OCOTP_CTRL_REG);
> > > > +
> > > > + writel(OCOTP_READ_CTRL_READ_FUSE,
> > > > + ocotp_base + OCOTP_READ_CTRL_REG);
> > > > + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + if (readl(ocotp_base) & OCOTP_CTRL_ERROR) {
> > > > + pr_err("Error reading from fuse address %d\n",
> > > > + valid_fuse_addr[i]);
> > >
> > > You could use dev_err() when storing vf610_ocotp_dev in the context.
> >
> > Ok.
> >
> > >
> > > > + writel(OCOTP_CTRL_ERROR, ocotp_base + OCOTP_CTRL_CLR);
> > >
> > > Shouldn't the function abort here?
> >
> > I am not sure about what usage I should follow here. I went for an
> > explicit error message and since 0xBADABADA is expected to be returned
> > on a read locked shadow register, the user would get the above for this
> > particular fuse address and the rest can still be valid since the TRM
> > mentions "subsequent reads to unlocked shadow locations will still work
> > successfully." So I did not abort on the error. Should I?
> 
> In case you don't want to abort, a comment about the 0xBADABADA behavior would
> be helpful.

Ok. Will add the same.

> 
> >
> > >
> > > > +
> > > > +
> > > > +static int vf610_ocotp_probe(struct platform_device *pdev)
> > > > +{
> > > > + struct vf610_ocotp_dev *ocotp_dev;
> > > > +
> > > > + ocotp_dev = devm_kzalloc(>dev,
> > > > + sizeof(struct vf610_ocotp_dev), GFP_KERNEL);
> > > > + if (!ocotp_dev)
> > > > + return -ENOMEM;
> > > > +
> > > > + ocotp_dev->dev = >dev;
> > > > +
> > > > + ocotp_dev->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > + ocotp_dev->base = devm_ioremap_resource(ocotp_dev->dev, 
> > > > ocotp_dev->res);
> > > > + if (IS_ERR(ocotp_dev->base))
> > > > + return PTR_ERR(ocotp_dev->base);
> > > > +
> > > > + ocotp_dev->clk = devm_clk_get(ocotp_dev->dev, "ocotp");
> > > > + if (IS_ERR(ocotp_dev->clk)) {
> > > > + dev_err(ocotp_dev->dev, "failed getting clock, err = %ld\n",
> > > > + PTR_ERR(ocotp_dev->clk));
> > > > + return PTR_ERR(ocotp_dev->clk);
> > > > + }
> > > > +
> > > > + ocotp_regmap_config.max_register = resource_size(ocotp_dev->res) - 1;
> > >
> > > Looking at valid_fuse_addr shows me 0x3F as last valid register. So the 
> > > rest
> > > of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case 

Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-07 Thread Stefan Wahren
Hi Sanchayan,

> maitysancha...@gmail.com hat am 7. Juli 2015 um 07:19 geschrieben:
>
>
> [...]
> > > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> > > index 17f1a57..84c830d 100644
> > > --- a/drivers/nvmem/Kconfig
> > > +++ b/drivers/nvmem/Kconfig
> > > @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
> > > This driver can also be built as a module. If so, the module
> > > will be called eeprom-sunxi-sid.
> > >
> > > +config NVMEM_VF610_OCOTP
> > > + tristate "VF610 SoCs OCOTP support"
> > > + depends on SOC_VF610
> > > + help
> > > + This is a driver for the 'OCOTP' available on various Vybrid
> > > + devices.
> >
> > I don't know much about Vybrid. But this driver is specific for VF610, isn't
> > it?
>
> Sorry. I only checked on VF50 and VF61. Will check if is it available with the
> other Vybrid devices and change if it is not so.

no problem. If you spend time in testing your driver with different devices, you
could mention
this in your patch description. The naming VF610 suggests that the driver is
very specific.
That confuses me a little bit.

>
> >
> > > +
> > > +
> > > +static int vf610_ocotp_write(void *context, const void *data, size_t
> > > count)
> > > +{
> > > + return 0;
> > > +}
> > > +
> > > +static int vf610_ocotp_read(void *context,
> > > + const void *offset, size_t reg_size,
> > > + void *val, size_t val_size)
> > > +{
> > > + void __iomem *ocotp_base = context;
> > > + u32 *buf = val;
> > > + u32 reg;
> > > + int ret;
> > > + int i;
> > > +
> > > + for (i = 0; i < ARRAY_SIZE(valid_fuse_addr); i++) {
> > > + vf610_ocotp_set_timing(ocotp_base, ocotp_timing);
> > > + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
> > > + if (ret)
> > > + return ret;
> >
> > Is it really necessary to set the timing in the loop, instead before?
>
> I will test it once. From my understanding of 35.3.1.5 I thought the timing
> needs to explicitly programmed on every read. Perhaps I took it too literally.

It was only a question. If barebox does the same, it should be okay.

>
> >
> > > +
> > > + reg = readl(ocotp_base + OCOTP_CTRL_REG);
> > > + reg &= ~OCOTP_CTRL_ADDR_MASK;
> > > + reg &= ~OCOTP_CTRL_WR_UNLOCK_MASK;
> > > + reg |= BF(valid_fuse_addr[i], OCOTP_CTRL_ADDR);
> > > + writel(reg, ocotp_base + OCOTP_CTRL_REG);
> > > +
> > > + writel(OCOTP_READ_CTRL_READ_FUSE,
> > > + ocotp_base + OCOTP_READ_CTRL_REG);
> > > + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + if (readl(ocotp_base) & OCOTP_CTRL_ERROR) {
> > > + pr_err("Error reading from fuse address %d\n",
> > > + valid_fuse_addr[i]);
> >
> > You could use dev_err() when storing vf610_ocotp_dev in the context.
>
> Ok.
>
> >
> > > + writel(OCOTP_CTRL_ERROR, ocotp_base + OCOTP_CTRL_CLR);
> >
> > Shouldn't the function abort here?
>
> I am not sure about what usage I should follow here. I went for an
> explicit error message and since 0xBADABADA is expected to be returned
> on a read locked shadow register, the user would get the above for this
> particular fuse address and the rest can still be valid since the TRM
> mentions "subsequent reads to unlocked shadow locations will still work
> successfully." So I did not abort on the error. Should I?

In case you don't want to abort, a comment about the 0xBADABADA behavior would
be helpful.

>
> >
> > > +
> > > +
> > > +static int vf610_ocotp_probe(struct platform_device *pdev)
> > > +{
> > > + struct vf610_ocotp_dev *ocotp_dev;
> > > +
> > > + ocotp_dev = devm_kzalloc(>dev,
> > > + sizeof(struct vf610_ocotp_dev), GFP_KERNEL);
> > > + if (!ocotp_dev)
> > > + return -ENOMEM;
> > > +
> > > + ocotp_dev->dev = >dev;
> > > +
> > > + ocotp_dev->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > + ocotp_dev->base = devm_ioremap_resource(ocotp_dev->dev, ocotp_dev->res);
> > > + if (IS_ERR(ocotp_dev->base))
> > > + return PTR_ERR(ocotp_dev->base);
> > > +
> > > + ocotp_dev->clk = devm_clk_get(ocotp_dev->dev, "ocotp");
> > > + if (IS_ERR(ocotp_dev->clk)) {
> > > + dev_err(ocotp_dev->dev, "failed getting clock, err = %ld\n",
> > > + PTR_ERR(ocotp_dev->clk));
> > > + return PTR_ERR(ocotp_dev->clk);
> > > + }
> > > +
> > > + ocotp_regmap_config.max_register = resource_size(ocotp_dev->res) - 1;
> >
> > Looking at valid_fuse_addr shows me 0x3F as last valid register. So the rest
> > of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw access
> > could be
> > uninitializied.
>
> Sorry I did not exactly get you here. The intention behind using the
> valid_fuse_addr
> is to allow reading only from valid fuse addresses and avoid reading from all
> other
> locations as per the Fuse map address table 35-1.

Yes, i got your intention. But from my unterstand the read function should fill
up
the complete buffer with defined values. My MXS OCOTP driver have the same
problem
and fill up the invalid registers with zero.

Regards
Stefan

>
> Thanks for the review.
>
> Regards,
> Sanchayan.
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-07 Thread Stefan Wahren
Hi Sanchayan,

 maitysancha...@gmail.com hat am 7. Juli 2015 um 07:19 geschrieben:


 [...]
   diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
   index 17f1a57..84c830d 100644
   --- a/drivers/nvmem/Kconfig
   +++ b/drivers/nvmem/Kconfig
   @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
   This driver can also be built as a module. If so, the module
   will be called eeprom-sunxi-sid.
  
   +config NVMEM_VF610_OCOTP
   + tristate VF610 SoCs OCOTP support
   + depends on SOC_VF610
   + help
   + This is a driver for the 'OCOTP' available on various Vybrid
   + devices.
 
  I don't know much about Vybrid. But this driver is specific for VF610, isn't
  it?

 Sorry. I only checked on VF50 and VF61. Will check if is it available with the
 other Vybrid devices and change if it is not so.

no problem. If you spend time in testing your driver with different devices, you
could mention
this in your patch description. The naming VF610 suggests that the driver is
very specific.
That confuses me a little bit.


 
   +
   +
   +static int vf610_ocotp_write(void *context, const void *data, size_t
   count)
   +{
   + return 0;
   +}
   +
   +static int vf610_ocotp_read(void *context,
   + const void *offset, size_t reg_size,
   + void *val, size_t val_size)
   +{
   + void __iomem *ocotp_base = context;
   + u32 *buf = val;
   + u32 reg;
   + int ret;
   + int i;
   +
   + for (i = 0; i  ARRAY_SIZE(valid_fuse_addr); i++) {
   + vf610_ocotp_set_timing(ocotp_base, ocotp_timing);
   + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
   + if (ret)
   + return ret;
 
  Is it really necessary to set the timing in the loop, instead before?

 I will test it once. From my understanding of 35.3.1.5 I thought the timing
 needs to explicitly programmed on every read. Perhaps I took it too literally.

It was only a question. If barebox does the same, it should be okay.


 
   +
   + reg = readl(ocotp_base + OCOTP_CTRL_REG);
   + reg = ~OCOTP_CTRL_ADDR_MASK;
   + reg = ~OCOTP_CTRL_WR_UNLOCK_MASK;
   + reg |= BF(valid_fuse_addr[i], OCOTP_CTRL_ADDR);
   + writel(reg, ocotp_base + OCOTP_CTRL_REG);
   +
   + writel(OCOTP_READ_CTRL_READ_FUSE,
   + ocotp_base + OCOTP_READ_CTRL_REG);
   + ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
   + if (ret)
   + return ret;
   +
   + if (readl(ocotp_base)  OCOTP_CTRL_ERROR) {
   + pr_err(Error reading from fuse address %d\n,
   + valid_fuse_addr[i]);
 
  You could use dev_err() when storing vf610_ocotp_dev in the context.

 Ok.

 
   + writel(OCOTP_CTRL_ERROR, ocotp_base + OCOTP_CTRL_CLR);
 
  Shouldn't the function abort here?

 I am not sure about what usage I should follow here. I went for an
 explicit error message and since 0xBADABADA is expected to be returned
 on a read locked shadow register, the user would get the above for this
 particular fuse address and the rest can still be valid since the TRM
 mentions subsequent reads to unlocked shadow locations will still work
 successfully. So I did not abort on the error. Should I?

In case you don't want to abort, a comment about the 0xBADABADA behavior would
be helpful.


 
   +
   +
   +static int vf610_ocotp_probe(struct platform_device *pdev)
   +{
   + struct vf610_ocotp_dev *ocotp_dev;
   +
   + ocotp_dev = devm_kzalloc(pdev-dev,
   + sizeof(struct vf610_ocotp_dev), GFP_KERNEL);
   + if (!ocotp_dev)
   + return -ENOMEM;
   +
   + ocotp_dev-dev = pdev-dev;
   +
   + ocotp_dev-res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
   + ocotp_dev-base = devm_ioremap_resource(ocotp_dev-dev, ocotp_dev-res);
   + if (IS_ERR(ocotp_dev-base))
   + return PTR_ERR(ocotp_dev-base);
   +
   + ocotp_dev-clk = devm_clk_get(ocotp_dev-dev, ocotp);
   + if (IS_ERR(ocotp_dev-clk)) {
   + dev_err(ocotp_dev-dev, failed getting clock, err = %ld\n,
   + PTR_ERR(ocotp_dev-clk));
   + return PTR_ERR(ocotp_dev-clk);
   + }
   +
   + ocotp_regmap_config.max_register = resource_size(ocotp_dev-res) - 1;
 
  Looking at valid_fuse_addr shows me 0x3F as last valid register. So the rest
  of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw access
  could be
  uninitializied.

 Sorry I did not exactly get you here. The intention behind using the
 valid_fuse_addr
 is to allow reading only from valid fuse addresses and avoid reading from all
 other
 locations as per the Fuse map address table 35-1.

Yes, i got your intention. But from my unterstand the read function should fill
up
the complete buffer with defined values. My MXS OCOTP driver have the same
problem
and fill up the invalid registers with zero.

Regards
Stefan


 Thanks for the review.

 Regards,
 Sanchayan.
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Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-07 Thread maitysanchayan
Hi Stefan,

On 15-07-07 14:49:06, Stefan Wahren wrote:
 Hi Sanchayan,
 
  maitysancha...@gmail.com hat am 7. Juli 2015 um 07:19 geschrieben:
 
 
  [...]
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 17f1a57..84c830d 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
This driver can also be built as a module. If so, the module
will be called eeprom-sunxi-sid.
   
+config NVMEM_VF610_OCOTP
+ tristate VF610 SoCs OCOTP support
+ depends on SOC_VF610
+ help
+ This is a driver for the 'OCOTP' available on various Vybrid
+ devices.
  
   I don't know much about Vybrid. But this driver is specific for VF610, 
   isn't
   it?
 
  Sorry. I only checked on VF50 and VF61. Will check if is it available with 
  the
  other Vybrid devices and change if it is not so.
 
 no problem. If you spend time in testing your driver with different devices, 
 you
 could mention
 this in your patch description. The naming VF610 suggests that the driver is
 very specific.
 That confuses me a little bit.

Sorry about that. Will add the necessary information in the next respin for 
sure.

 
 
  
+
+
+static int vf610_ocotp_write(void *context, const void *data, size_t
count)
+{
+ return 0;
+}
+
+static int vf610_ocotp_read(void *context,
+ const void *offset, size_t reg_size,
+ void *val, size_t val_size)
+{
+ void __iomem *ocotp_base = context;
+ u32 *buf = val;
+ u32 reg;
+ int ret;
+ int i;
+
+ for (i = 0; i  ARRAY_SIZE(valid_fuse_addr); i++) {
+ vf610_ocotp_set_timing(ocotp_base, ocotp_timing);
+ ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
+ if (ret)
+ return ret;
  
   Is it really necessary to set the timing in the loop, instead before?
 
  I will test it once. From my understanding of 35.3.1.5 I thought the timing
  needs to explicitly programmed on every read. Perhaps I took it too 
  literally.
 
 It was only a question. If barebox does the same, it should be okay.


Yes, the code logic is completely similar to barebox except for changes like
how timeout is handled here in the wait busy function.

 
  
+
+ reg = readl(ocotp_base + OCOTP_CTRL_REG);
+ reg = ~OCOTP_CTRL_ADDR_MASK;
+ reg = ~OCOTP_CTRL_WR_UNLOCK_MASK;
+ reg |= BF(valid_fuse_addr[i], OCOTP_CTRL_ADDR);
+ writel(reg, ocotp_base + OCOTP_CTRL_REG);
+
+ writel(OCOTP_READ_CTRL_READ_FUSE,
+ ocotp_base + OCOTP_READ_CTRL_REG);
+ ret = vf610_ocotp_wait_busy(ocotp_base + OCOTP_CTRL_REG);
+ if (ret)
+ return ret;
+
+ if (readl(ocotp_base)  OCOTP_CTRL_ERROR) {
+ pr_err(Error reading from fuse address %d\n,
+ valid_fuse_addr[i]);
  
   You could use dev_err() when storing vf610_ocotp_dev in the context.
 
  Ok.
 
  
+ writel(OCOTP_CTRL_ERROR, ocotp_base + OCOTP_CTRL_CLR);
  
   Shouldn't the function abort here?
 
  I am not sure about what usage I should follow here. I went for an
  explicit error message and since 0xBADABADA is expected to be returned
  on a read locked shadow register, the user would get the above for this
  particular fuse address and the rest can still be valid since the TRM
  mentions subsequent reads to unlocked shadow locations will still work
  successfully. So I did not abort on the error. Should I?
 
 In case you don't want to abort, a comment about the 0xBADABADA behavior would
 be helpful.

Ok. Will add the same.

 
 
  
+
+
+static int vf610_ocotp_probe(struct platform_device *pdev)
+{
+ struct vf610_ocotp_dev *ocotp_dev;
+
+ ocotp_dev = devm_kzalloc(pdev-dev,
+ sizeof(struct vf610_ocotp_dev), GFP_KERNEL);
+ if (!ocotp_dev)
+ return -ENOMEM;
+
+ ocotp_dev-dev = pdev-dev;
+
+ ocotp_dev-res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ocotp_dev-base = devm_ioremap_resource(ocotp_dev-dev, 
ocotp_dev-res);
+ if (IS_ERR(ocotp_dev-base))
+ return PTR_ERR(ocotp_dev-base);
+
+ ocotp_dev-clk = devm_clk_get(ocotp_dev-dev, ocotp);
+ if (IS_ERR(ocotp_dev-clk)) {
+ dev_err(ocotp_dev-dev, failed getting clock, err = %ld\n,
+ PTR_ERR(ocotp_dev-clk));
+ return PTR_ERR(ocotp_dev-clk);
+ }
+
+ ocotp_regmap_config.max_register = resource_size(ocotp_dev-res) - 1;
  
   Looking at valid_fuse_addr shows me 0x3F as last valid register. So the 
   rest
   of the buffer ( 0xD00 - sizeof(valid_fuse_addr) ) in case of raw access
   could be
   uninitializied.
 
  Sorry I did not exactly get you here. The intention behind using the
  valid_fuse_addr
  is to allow reading only from valid fuse addresses and avoid reading from 
  all
  other
  locations as per the Fuse map address table 35-1.
 
 Yes, i got your intention. But from my unterstand the read function should 
 fill
 up
 the complete buffer with defined values. My MXS OCOTP driver have the same
 problem
 and fill 

Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-06 Thread maitysanchayan
Hello Stefan,

On 15-07-06 12:16:34, Stefan Wahren wrote:
> Hi Sanchayan,
> 
> > Sanchayan Maity  hat am 29. Juni 2015 um 13:22
> > geschrieben:
> >
> >
> > The patch adds support for the On Chip One Time Programmable Peripheral
> > (OCOTP) on the Vybrid platform.
> 
> please provide a changelog in your cover letter and a new version after 
> changes.
> 
> I think it's important to note that the driver only support read-only access.

Ok. Will mention this explicitly in the next version.

> 
> >
> > Signed-off-by: Sanchayan Maity 
> > ---
> > drivers/nvmem/Kconfig | 10 ++
> > drivers/nvmem/Makefile | 2 +
> > drivers/nvmem/vf610-ocotp.c | 250 
> > 
> > 3 files changed, 262 insertions(+)
> > create mode 100644 drivers/nvmem/vf610-ocotp.c
> >
> > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> > index 17f1a57..84c830d 100644
> > --- a/drivers/nvmem/Kconfig
> > +++ b/drivers/nvmem/Kconfig
> > @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
> > This driver can also be built as a module. If so, the module
> > will be called eeprom-sunxi-sid.
> >
> > +config NVMEM_VF610_OCOTP
> > + tristate "VF610 SoCs OCOTP support"
> > + depends on SOC_VF610
> > + help
> > + This is a driver for the 'OCOTP' available on various Vybrid
> > + devices.
> 
> I don't know much about Vybrid. But this driver is specific for VF610, isn't 
> it?

Sorry. I only checked on VF50 and VF61. Will check if is it available with the
other Vybrid devices and change if it is not so.

> 
> > +
> > + This driver can also be built as a module. If so, the module
> > + will be called nvmem-vf610-ocotp.
> > +
> > endif
> > diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> > index cc46791..a9ed113 100644
> > --- a/drivers/nvmem/Makefile
> > +++ b/drivers/nvmem/Makefile
> > @@ -11,3 +11,5 @@ obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
> > nvmem_qfprom-y := qfprom.o
> > obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem-sunxi-sid.o
> > nvmem-sunxi-sid-y := sunxi-sid.o
> > +obj-$(CONFIG_NVMEM_VF610_OCOTP) += nvmem-vf610-ocotp.o
> > +nvmem-vf610-ocotp-y := vf610-ocotp.o
> > diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
> > new file mode 100644
> > index 000..b7a782c
> > --- /dev/null
> > +++ b/drivers/nvmem/vf610-ocotp.c
> > @@ -0,0 +1,250 @@
> > +/*
> > + * Copyright (C) 2015 Sanchayan Maity 
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 and
> > + * only version 2 as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +
> > +/* OCOTP Register Offsets */
> > +#define OCOTP_CTRL_REG 0x00
> > +#define OCOTP_CTRL_SET 0x04
> > +#define OCOTP_CTRL_CLR 0x08
> > +#define OCOTP_TIMING 0x10
> > +#define OCOTP_DATA 0x20
> > +#define OCOTP_READ_CTRL_REG 0x30
> > +#define OCOTP_READ_FUSE_DATA 0x40
> > +
> > +/* OCOTP Register bits and masks */
> > +#define OCOTP_CTRL_WR_UNLOCK 16
> > +#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
> > +#define OCOTP_CTRL_WR_UNLOCK_MASK 0x
> > +#define OCOTP_CTRL_ADDR 0
> > +#define OCOTP_CTRL_ADDR_MASK 0x7F
> > +#define OCOTP_CTRL_RELOAD_SHADOWS (0x1 << 10)
> > +#define OCOTP_CTRL_ERROR (0x1 << 9)
> > +#define OCOTP_CTRL_BUSY (0x1 << 8)
> 
> You can use the BIT() macro here.

Ok.

> 
> > +
> > +#define OCOTP_TIMING_STROBE_READ 16
> > +#define OCOTP_TIMING_STROBE_READ_MASK 0x003F
> > +#define OCOTP_TIMING_RELAX 12
> > +#define OCOTP_TIMING_RELAX_MASK 0xF000
> > +#define OCOTP_TIMING_STROBE_PROG 0
> > +#define OCOTP_TIMING_STROBE_PROG_MASK 0x0FFF
> > +
> > +#define OCOTP_READ_CTRL_READ_FUSE 0x1
> > +
> > +#define VF610_OCOTP_TIMEOUT 10
> > +
> > +#define BF(value, field) (((value) << field) & field##_MASK)
> > +
> > +#define DEF_RELAX 20
> > +
> > +struct vf610_ocotp_dev {
> > + void __iomem *base;
> > + struct clk *clk;
> > + struct device *dev;
> > + struct resource *res;
> > + struct regmap *regmap;
> > + struct nvmem_device *nvmem;
> > +};
> 
> Some member of this struct seems unnecessary to me. Please
> remove the unused one.
> 
> > +
> > +static int ocotp_timing;
> 
> How about storing the timings in struct above?

Ok.

> 
> > +
> > +static u8 valid_fuse_addr[] = {
> > + 0x00, 0x01, 0x02, 0x04, 0x0F, 0x20, 0x21, 0x22, 0x23, 0x24,
> > + 0x25, 0x26, 0x27, 0x28, 0x2F, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
> > + 0x3D, 0x3E, 0x3F
> > +};
> 
> const?

Right.

> 
> > +
> > +static int vf610_ocotp_wait_busy(void __iomem *base)
> > +{
> > + int timeout = VF610_OCOTP_TIMEOUT;
> > +
> > + while ((readl(base) & 

Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-06 Thread Stefan Wahren
Hi Sanchayan,

> Sanchayan Maity  hat am 29. Juni 2015 um 13:22
> geschrieben:
>
>
> The patch adds support for the On Chip One Time Programmable Peripheral
> (OCOTP) on the Vybrid platform.

please provide a changelog in your cover letter and a new version after changes.

I think it's important to note that the driver only support read-only access.

>
> Signed-off-by: Sanchayan Maity 
> ---
> drivers/nvmem/Kconfig | 10 ++
> drivers/nvmem/Makefile | 2 +
> drivers/nvmem/vf610-ocotp.c | 250 
> 3 files changed, 262 insertions(+)
> create mode 100644 drivers/nvmem/vf610-ocotp.c
>
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 17f1a57..84c830d 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
> This driver can also be built as a module. If so, the module
> will be called eeprom-sunxi-sid.
>
> +config NVMEM_VF610_OCOTP
> + tristate "VF610 SoCs OCOTP support"
> + depends on SOC_VF610
> + help
> + This is a driver for the 'OCOTP' available on various Vybrid
> + devices.

I don't know much about Vybrid. But this driver is specific for VF610, isn't it?

> +
> + This driver can also be built as a module. If so, the module
> + will be called nvmem-vf610-ocotp.
> +
> endif
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index cc46791..a9ed113 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -11,3 +11,5 @@ obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
> nvmem_qfprom-y := qfprom.o
> obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem-sunxi-sid.o
> nvmem-sunxi-sid-y := sunxi-sid.o
> +obj-$(CONFIG_NVMEM_VF610_OCOTP) += nvmem-vf610-ocotp.o
> +nvmem-vf610-ocotp-y := vf610-ocotp.o
> diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
> new file mode 100644
> index 000..b7a782c
> --- /dev/null
> +++ b/drivers/nvmem/vf610-ocotp.c
> @@ -0,0 +1,250 @@
> +/*
> + * Copyright (C) 2015 Sanchayan Maity 
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +/* OCOTP Register Offsets */
> +#define OCOTP_CTRL_REG 0x00
> +#define OCOTP_CTRL_SET 0x04
> +#define OCOTP_CTRL_CLR 0x08
> +#define OCOTP_TIMING 0x10
> +#define OCOTP_DATA 0x20
> +#define OCOTP_READ_CTRL_REG 0x30
> +#define OCOTP_READ_FUSE_DATA 0x40
> +
> +/* OCOTP Register bits and masks */
> +#define OCOTP_CTRL_WR_UNLOCK 16
> +#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
> +#define OCOTP_CTRL_WR_UNLOCK_MASK 0x
> +#define OCOTP_CTRL_ADDR 0
> +#define OCOTP_CTRL_ADDR_MASK 0x7F
> +#define OCOTP_CTRL_RELOAD_SHADOWS (0x1 << 10)
> +#define OCOTP_CTRL_ERROR (0x1 << 9)
> +#define OCOTP_CTRL_BUSY (0x1 << 8)

You can use the BIT() macro here.

> +
> +#define OCOTP_TIMING_STROBE_READ 16
> +#define OCOTP_TIMING_STROBE_READ_MASK 0x003F
> +#define OCOTP_TIMING_RELAX 12
> +#define OCOTP_TIMING_RELAX_MASK 0xF000
> +#define OCOTP_TIMING_STROBE_PROG 0
> +#define OCOTP_TIMING_STROBE_PROG_MASK 0x0FFF
> +
> +#define OCOTP_READ_CTRL_READ_FUSE 0x1
> +
> +#define VF610_OCOTP_TIMEOUT 10
> +
> +#define BF(value, field) (((value) << field) & field##_MASK)
> +
> +#define DEF_RELAX 20
> +
> +struct vf610_ocotp_dev {
> + void __iomem *base;
> + struct clk *clk;
> + struct device *dev;
> + struct resource *res;
> + struct regmap *regmap;
> + struct nvmem_device *nvmem;
> +};

Some member of this struct seems unnecessary to me. Please
remove the unused one.

> +
> +static int ocotp_timing;

How about storing the timings in struct above?

> +
> +static u8 valid_fuse_addr[] = {
> + 0x00, 0x01, 0x02, 0x04, 0x0F, 0x20, 0x21, 0x22, 0x23, 0x24,
> + 0x25, 0x26, 0x27, 0x28, 0x2F, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
> + 0x3D, 0x3E, 0x3F
> +};

const?

> +
> +static int vf610_ocotp_wait_busy(void __iomem *base)
> +{
> + int timeout = VF610_OCOTP_TIMEOUT;
> +
> + while ((readl(base) & OCOTP_CTRL_BUSY) && --timeout)
> + udelay(10);
> +
> + if (!timeout) {
> + writel(OCOTP_CTRL_ERROR, base + OCOTP_CTRL_CLR);
> + return -ETIMEDOUT;
> + }
> +
> + udelay(10);
> +
> + return 0;
> +}
> +
> +static int vf610_ocotp_calculate_timing(struct vf610_ocotp_dev *ocotp_dev)
> +{
> + u32 clk_rate;
> + u32 relax, strobe_read, strobe_prog;
> + u32 timing;
> +
> + clk_rate = clk_get_rate(ocotp_dev->clk);

If clk_get_rate() fails, then we should abort with a warning.

> +
> + relax = clk_rate / (10 / DEF_RELAX) - 1;
> + strobe_prog = clk_rate / (10 / 1) + 2 * (DEF_RELAX 

Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-06 Thread Stefan Wahren
Hi Sanchayan,

 Sanchayan Maity maitysancha...@gmail.com hat am 29. Juni 2015 um 13:22
 geschrieben:


 The patch adds support for the On Chip One Time Programmable Peripheral
 (OCOTP) on the Vybrid platform.

please provide a changelog in your cover letter and a new version after changes.

I think it's important to note that the driver only support read-only access.


 Signed-off-by: Sanchayan Maity maitysancha...@gmail.com
 ---
 drivers/nvmem/Kconfig | 10 ++
 drivers/nvmem/Makefile | 2 +
 drivers/nvmem/vf610-ocotp.c | 250 
 3 files changed, 262 insertions(+)
 create mode 100644 drivers/nvmem/vf610-ocotp.c

 diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
 index 17f1a57..84c830d 100644
 --- a/drivers/nvmem/Kconfig
 +++ b/drivers/nvmem/Kconfig
 @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
 This driver can also be built as a module. If so, the module
 will be called eeprom-sunxi-sid.

 +config NVMEM_VF610_OCOTP
 + tristate VF610 SoCs OCOTP support
 + depends on SOC_VF610
 + help
 + This is a driver for the 'OCOTP' available on various Vybrid
 + devices.

I don't know much about Vybrid. But this driver is specific for VF610, isn't it?

 +
 + This driver can also be built as a module. If so, the module
 + will be called nvmem-vf610-ocotp.
 +
 endif
 diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
 index cc46791..a9ed113 100644
 --- a/drivers/nvmem/Makefile
 +++ b/drivers/nvmem/Makefile
 @@ -11,3 +11,5 @@ obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
 nvmem_qfprom-y := qfprom.o
 obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem-sunxi-sid.o
 nvmem-sunxi-sid-y := sunxi-sid.o
 +obj-$(CONFIG_NVMEM_VF610_OCOTP) += nvmem-vf610-ocotp.o
 +nvmem-vf610-ocotp-y := vf610-ocotp.o
 diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
 new file mode 100644
 index 000..b7a782c
 --- /dev/null
 +++ b/drivers/nvmem/vf610-ocotp.c
 @@ -0,0 +1,250 @@
 +/*
 + * Copyright (C) 2015 Sanchayan Maity sanchayan.ma...@toradex.com
 + *
 + * This program is free software; you can redistribute it and/or modify
 + * it under the terms of the GNU General Public License version 2 and
 + * only version 2 as published by the Free Software Foundation.
 + *
 + * This program is distributed in the hope that it will be useful,
 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 + * GNU General Public License for more details.
 + */
 +
 +#include linux/clk.h
 +#include linux/delay.h
 +#include linux/device.h
 +#include linux/nvmem-provider.h
 +#include linux/io.h
 +#include linux/module.h
 +#include linux/of.h
 +#include linux/platform_device.h
 +#include linux/regmap.h
 +#include linux/slab.h
 +
 +/* OCOTP Register Offsets */
 +#define OCOTP_CTRL_REG 0x00
 +#define OCOTP_CTRL_SET 0x04
 +#define OCOTP_CTRL_CLR 0x08
 +#define OCOTP_TIMING 0x10
 +#define OCOTP_DATA 0x20
 +#define OCOTP_READ_CTRL_REG 0x30
 +#define OCOTP_READ_FUSE_DATA 0x40
 +
 +/* OCOTP Register bits and masks */
 +#define OCOTP_CTRL_WR_UNLOCK 16
 +#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
 +#define OCOTP_CTRL_WR_UNLOCK_MASK 0x
 +#define OCOTP_CTRL_ADDR 0
 +#define OCOTP_CTRL_ADDR_MASK 0x7F
 +#define OCOTP_CTRL_RELOAD_SHADOWS (0x1  10)
 +#define OCOTP_CTRL_ERROR (0x1  9)
 +#define OCOTP_CTRL_BUSY (0x1  8)

You can use the BIT() macro here.

 +
 +#define OCOTP_TIMING_STROBE_READ 16
 +#define OCOTP_TIMING_STROBE_READ_MASK 0x003F
 +#define OCOTP_TIMING_RELAX 12
 +#define OCOTP_TIMING_RELAX_MASK 0xF000
 +#define OCOTP_TIMING_STROBE_PROG 0
 +#define OCOTP_TIMING_STROBE_PROG_MASK 0x0FFF
 +
 +#define OCOTP_READ_CTRL_READ_FUSE 0x1
 +
 +#define VF610_OCOTP_TIMEOUT 10
 +
 +#define BF(value, field) (((value)  field)  field##_MASK)
 +
 +#define DEF_RELAX 20
 +
 +struct vf610_ocotp_dev {
 + void __iomem *base;
 + struct clk *clk;
 + struct device *dev;
 + struct resource *res;
 + struct regmap *regmap;
 + struct nvmem_device *nvmem;
 +};

Some member of this struct seems unnecessary to me. Please
remove the unused one.

 +
 +static int ocotp_timing;

How about storing the timings in struct above?

 +
 +static u8 valid_fuse_addr[] = {
 + 0x00, 0x01, 0x02, 0x04, 0x0F, 0x20, 0x21, 0x22, 0x23, 0x24,
 + 0x25, 0x26, 0x27, 0x28, 0x2F, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
 + 0x3D, 0x3E, 0x3F
 +};

const?

 +
 +static int vf610_ocotp_wait_busy(void __iomem *base)
 +{
 + int timeout = VF610_OCOTP_TIMEOUT;
 +
 + while ((readl(base)  OCOTP_CTRL_BUSY)  --timeout)
 + udelay(10);
 +
 + if (!timeout) {
 + writel(OCOTP_CTRL_ERROR, base + OCOTP_CTRL_CLR);
 + return -ETIMEDOUT;
 + }
 +
 + udelay(10);
 +
 + return 0;
 +}
 +
 +static int vf610_ocotp_calculate_timing(struct vf610_ocotp_dev *ocotp_dev)
 +{
 + u32 clk_rate;
 + u32 relax, strobe_read, strobe_prog;
 + u32 timing;
 +
 + clk_rate = clk_get_rate(ocotp_dev-clk);

If clk_get_rate() fails, then we should abort with a warning.

 +
 + relax = clk_rate / (10 / DEF_RELAX) - 1;
 + strobe_prog 

Re: [RFC PATCH v6 3/3] drivers: nvmem: Add Vybrid OCOTP support

2015-07-06 Thread maitysanchayan
Hello Stefan,

On 15-07-06 12:16:34, Stefan Wahren wrote:
 Hi Sanchayan,
 
  Sanchayan Maity maitysancha...@gmail.com hat am 29. Juni 2015 um 13:22
  geschrieben:
 
 
  The patch adds support for the On Chip One Time Programmable Peripheral
  (OCOTP) on the Vybrid platform.
 
 please provide a changelog in your cover letter and a new version after 
 changes.
 
 I think it's important to note that the driver only support read-only access.

Ok. Will mention this explicitly in the next version.

 
 
  Signed-off-by: Sanchayan Maity maitysancha...@gmail.com
  ---
  drivers/nvmem/Kconfig | 10 ++
  drivers/nvmem/Makefile | 2 +
  drivers/nvmem/vf610-ocotp.c | 250 
  
  3 files changed, 262 insertions(+)
  create mode 100644 drivers/nvmem/vf610-ocotp.c
 
  diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
  index 17f1a57..84c830d 100644
  --- a/drivers/nvmem/Kconfig
  +++ b/drivers/nvmem/Kconfig
  @@ -33,4 +33,14 @@ config NVMEM_SUNXI_SID
  This driver can also be built as a module. If so, the module
  will be called eeprom-sunxi-sid.
 
  +config NVMEM_VF610_OCOTP
  + tristate VF610 SoCs OCOTP support
  + depends on SOC_VF610
  + help
  + This is a driver for the 'OCOTP' available on various Vybrid
  + devices.
 
 I don't know much about Vybrid. But this driver is specific for VF610, isn't 
 it?

Sorry. I only checked on VF50 and VF61. Will check if is it available with the
other Vybrid devices and change if it is not so.

 
  +
  + This driver can also be built as a module. If so, the module
  + will be called nvmem-vf610-ocotp.
  +
  endif
  diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
  index cc46791..a9ed113 100644
  --- a/drivers/nvmem/Makefile
  +++ b/drivers/nvmem/Makefile
  @@ -11,3 +11,5 @@ obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
  nvmem_qfprom-y := qfprom.o
  obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem-sunxi-sid.o
  nvmem-sunxi-sid-y := sunxi-sid.o
  +obj-$(CONFIG_NVMEM_VF610_OCOTP) += nvmem-vf610-ocotp.o
  +nvmem-vf610-ocotp-y := vf610-ocotp.o
  diff --git a/drivers/nvmem/vf610-ocotp.c b/drivers/nvmem/vf610-ocotp.c
  new file mode 100644
  index 000..b7a782c
  --- /dev/null
  +++ b/drivers/nvmem/vf610-ocotp.c
  @@ -0,0 +1,250 @@
  +/*
  + * Copyright (C) 2015 Sanchayan Maity sanchayan.ma...@toradex.com
  + *
  + * This program is free software; you can redistribute it and/or modify
  + * it under the terms of the GNU General Public License version 2 and
  + * only version 2 as published by the Free Software Foundation.
  + *
  + * This program is distributed in the hope that it will be useful,
  + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  + * GNU General Public License for more details.
  + */
  +
  +#include linux/clk.h
  +#include linux/delay.h
  +#include linux/device.h
  +#include linux/nvmem-provider.h
  +#include linux/io.h
  +#include linux/module.h
  +#include linux/of.h
  +#include linux/platform_device.h
  +#include linux/regmap.h
  +#include linux/slab.h
  +
  +/* OCOTP Register Offsets */
  +#define OCOTP_CTRL_REG 0x00
  +#define OCOTP_CTRL_SET 0x04
  +#define OCOTP_CTRL_CLR 0x08
  +#define OCOTP_TIMING 0x10
  +#define OCOTP_DATA 0x20
  +#define OCOTP_READ_CTRL_REG 0x30
  +#define OCOTP_READ_FUSE_DATA 0x40
  +
  +/* OCOTP Register bits and masks */
  +#define OCOTP_CTRL_WR_UNLOCK 16
  +#define OCOTP_CTRL_WR_UNLOCK_KEY 0x3E77
  +#define OCOTP_CTRL_WR_UNLOCK_MASK 0x
  +#define OCOTP_CTRL_ADDR 0
  +#define OCOTP_CTRL_ADDR_MASK 0x7F
  +#define OCOTP_CTRL_RELOAD_SHADOWS (0x1  10)
  +#define OCOTP_CTRL_ERROR (0x1  9)
  +#define OCOTP_CTRL_BUSY (0x1  8)
 
 You can use the BIT() macro here.

Ok.

 
  +
  +#define OCOTP_TIMING_STROBE_READ 16
  +#define OCOTP_TIMING_STROBE_READ_MASK 0x003F
  +#define OCOTP_TIMING_RELAX 12
  +#define OCOTP_TIMING_RELAX_MASK 0xF000
  +#define OCOTP_TIMING_STROBE_PROG 0
  +#define OCOTP_TIMING_STROBE_PROG_MASK 0x0FFF
  +
  +#define OCOTP_READ_CTRL_READ_FUSE 0x1
  +
  +#define VF610_OCOTP_TIMEOUT 10
  +
  +#define BF(value, field) (((value)  field)  field##_MASK)
  +
  +#define DEF_RELAX 20
  +
  +struct vf610_ocotp_dev {
  + void __iomem *base;
  + struct clk *clk;
  + struct device *dev;
  + struct resource *res;
  + struct regmap *regmap;
  + struct nvmem_device *nvmem;
  +};
 
 Some member of this struct seems unnecessary to me. Please
 remove the unused one.
 
  +
  +static int ocotp_timing;
 
 How about storing the timings in struct above?

Ok.

 
  +
  +static u8 valid_fuse_addr[] = {
  + 0x00, 0x01, 0x02, 0x04, 0x0F, 0x20, 0x21, 0x22, 0x23, 0x24,
  + 0x25, 0x26, 0x27, 0x28, 0x2F, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
  + 0x3D, 0x3E, 0x3F
  +};
 
 const?

Right.

 
  +
  +static int vf610_ocotp_wait_busy(void __iomem *base)
  +{
  + int timeout = VF610_OCOTP_TIMEOUT;
  +
  + while ((readl(base)  OCOTP_CTRL_BUSY)  --timeout)
  + udelay(10);
  +
  + if (!timeout) {
  +