2016-04-08 21:21:56

by Fei Yang

[permalink] [raw]
Subject: [PATCH] IOSF: Add interface for the cases requiring fid

From: Fei Yang <[email protected]>

Some implementations may require an additional step for setting the FID
bits to ensure correct transactions over the IOSF side band interface.
Add the FID support accordingly for such implementations

Change-Id: Ic0227f9e74133a3203aa08e8471939f905d19622
Signed-off-by: Fei Yang <[email protected]>
---
arch/x86/include/asm/iosf_mbi.h | 27 ++++++++++++++
arch/x86/platform/intel/iosf_mbi.c | 73 ++++++++++++++++++++++++++++++++++++++
2 files changed, 100 insertions(+)

diff --git a/arch/x86/include/asm/iosf_mbi.h b/arch/x86/include/asm/iosf_mbi.h
index b41ee16..71511ba 100644
--- a/arch/x86/include/asm/iosf_mbi.h
+++ b/arch/x86/include/asm/iosf_mbi.h
@@ -8,6 +8,7 @@
#define MBI_MCR_OFFSET 0xD0
#define MBI_MDR_OFFSET 0xD4
#define MBI_MCRX_OFFSET 0xD8
+#define MBI_MCRP_OFFSET 0xDC

#define MBI_RD_MASK 0xFEFFFFFF
#define MBI_WR_MASK 0X01000000
@@ -88,6 +89,32 @@ int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr);
*/
int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask);

+/**
+ * iosf_mbi_read_with_fid() - MailBox Interface read command requiring fid
+ * @fid: fid bits
+ * @port: port indicating subunit being accessed
+ * @opcode: port specific read or write opcode
+ * @offset: register address offset
+ * @mdr: register data to be read
+ *
+ * Locking is handled by spinlock - cannot sleep.
+ * Return: Nonzero on error
+ */
+int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset, u32 *mdr);
+
+/**
+ * iosf_mbi_write_with_fid() - MailBox unmasked write command requiring fid
+ * @fid: fid bits
+ * @port: port indicating subunit being accessed
+ * @opcode: port specific read or write opcode
+ * @offset: register address offset
+ * @mdr: register data to be written
+ *
+ * Locking is handled by spinlock - cannot sleep.
+ * Return: Nonzero on error
+ */
+int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset, u32 mdr);
+
#else /* CONFIG_IOSF_MBI is not enabled */
static inline
bool iosf_mbi_available(void)
diff --git a/arch/x86/platform/intel/iosf_mbi.c b/arch/x86/platform/intel/iosf_mbi.c
index edf2c54..af182c1 100644
--- a/arch/x86/platform/intel/iosf_mbi.c
+++ b/arch/x86/platform/intel/iosf_mbi.c
@@ -98,6 +98,24 @@ fail_write:
return result;
}

+static int iosf_mbi_pci_write_fid(u32 fid)
+{
+ int result;
+
+ if (!mbi_pdev)
+ return -ENODEV;
+
+ result = pci_write_config_dword(mbi_pdev, MBI_MCRP_OFFSET, fid);
+ if (result < 0)
+ goto fail_fid_write;
+
+ return 0;
+
+fail_fid_write:
+ dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n", result);
+ return result;
+}
+
int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr)
{
u32 mcr, mcrx;
@@ -183,6 +201,61 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask)
}
EXPORT_SYMBOL(iosf_mbi_modify);

+/*
+ * Some IP blocks require fid to access their registers.
+ * fid value is programmed through MCRP register, see above function
+ * iosf_mbi_pci_write_fid() for details.
+ */
+int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset, u32 *mdr)
+{
+ u32 mcr, mcrx;
+ unsigned long flags;
+ int ret;
+
+ /*Access to the GFX unit is handled by GPU code */
+ if (port == BT_MBI_UNIT_GFX) {
+ WARN_ON(1);
+ return -EPERM;
+ }
+
+ mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
+ mcrx = offset & MBI_MASK_HI;
+
+ spin_lock_irqsave(&iosf_mbi_lock, flags);
+ ret = iosf_mbi_pci_write_fid(fid);
+ if (!ret)
+ ret = iosf_mbi_pci_read_mdr(mcrx, mcr, mdr);
+ spin_unlock_irqrestore(&iosf_mbi_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(iosf_mbi_read_with_fid);
+
+int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset, u32 mdr)
+{
+ u32 mcr, mcrx;
+ unsigned long flags;
+ int ret;
+
+ /*Access to the GFX unit is handled by GPU code */
+ if (port == BT_MBI_UNIT_GFX) {
+ WARN_ON(1);
+ return -EPERM;
+ }
+
+ mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
+ mcrx = offset & MBI_MASK_HI;
+
+ spin_lock_irqsave(&iosf_mbi_lock, flags);
+ ret = iosf_mbi_pci_write_fid(fid);
+ if (!ret)
+ ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr);
+ spin_unlock_irqrestore(&iosf_mbi_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(iosf_mbi_write_with_fid);
+
bool iosf_mbi_available(void)
{
/* Mbi isn't hot-pluggable. No remove routine is provided */
--
1.9.1


2016-04-11 10:25:46

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH] IOSF: Add interface for the cases requiring fid

On Fri, 2016-04-08 at 14:02 -0700, Fei Yang wrote:
> From: Fei Yang <[email protected]>
>

In subject better to use x86/platform/iosf_mbi prefix.

> Some implementations may require an additional step for setting the
> FID

What FID stands for?

> bits to ensure correct transactions over the IOSF side band interface.
> Add the FID support accordingly for such implementations
>


> Change-Id: Ic0227f9e74133a3203aa08e8471939f905d19622

This should not be here.

> --- a/arch/x86/include/asm/iosf_mbi.h
> +++ b/arch/x86/include/asm/iosf_mbi.h

> @@ -88,6 +89,32 @@ int iosf_mbi_write(u8 port, u8 opcode, u32 offset,
> u32 mdr);
>   */
>  int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32
> mask);
>  
> +/**
> + * iosf_mbi_read_with_fid() - MailBox Interface read command
> requiring fid
> + * @fid: fid bits
> + * @port: port indicating subunit being accessed
> + * @opcode: port specific read or write opcode
> + * @offset: register address offset
> + * @mdr: register data to be read
> + *
> + * Locking is handled by spinlock - cannot sleep.
> + * Return: Nonzero on error
> + */
> +int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 *mdr);
> +
> +/**
> + * iosf_mbi_write_with_fid() - MailBox unmasked write command
> requiring fid
> + * @fid: fid bits
> + * @port: port indicating subunit being accessed
> + * @opcode: port specific read or write opcode
> + * @offset: register address offset
> + * @mdr: register data to be written
> + *
> + * Locking is handled by spinlock - cannot sleep.
> + * Return: Nonzero on error
> + */
> +int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 mdr);
> +
>  #else /* CONFIG_IOSF_MBI is not enabled */
>  static inline
>  bool iosf_mbi_available(void)
> diff --git a/arch/x86/platform/intel/iosf_mbi.c
> b/arch/x86/platform/intel/iosf_mbi.c
> index edf2c54..af182c1 100644
> --- a/arch/x86/platform/intel/iosf_mbi.c
> +++ b/arch/x86/platform/intel/iosf_mbi.c
> @@ -98,6 +98,24 @@ fail_write:
>   return result;
>  }
>  
> +static int iosf_mbi_pci_write_fid(u32 fid)

Function name should continue already used pattern, i.e.
…_write_mcrp()


> +{
> + int result;
> +
> + if (!mbi_pdev)
> + return -ENODEV;
> +


> + result = pci_write_config_dword(mbi_pdev, MBI_MCRP_OFFSET,
> fid);

The function of one line.
So, please, inline it directly where it's used.


> + if (result < 0)
> + goto fail_fid_write;
> +
> + return 0;
> +
> +fail_fid_write:
> + dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n",
> result);
> + return result;
> +}
> +
>  int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr)
>  {
>   u32 mcr, mcrx;
> @@ -183,6 +201,61 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32
> offset, u32 mdr, u32 mask)
>  }
>  EXPORT_SYMBOL(iosf_mbi_modify);
>  
> +/*
> + * Some IP blocks require fid to access their registers.

Any user?
This API doesn't make much sense without user.

> + * fid value is programmed through MCRP register, see above function
> + * iosf_mbi_pci_write_fid() for details.
> + */
> +int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 *mdr)

Name kinda fuzzy. How user should know which one to choose? Does fid ==
0 work for some cases? We have to think about API and naming.

> +{
> + u32 mcr, mcrx;
> + unsigned long flags;
> + int ret;
> +
> + /*Access to the GFX unit is handled by GPU code */

Spaces.

> + if (port == BT_MBI_UNIT_GFX) {
> + WARN_ON(1);
> + return -EPERM;
> + }
> +
> + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
> + mcrx = offset & MBI_MASK_HI;
> +
> + spin_lock_irqsave(&iosf_mbi_lock, flags);
> + ret = iosf_mbi_pci_write_fid(fid);
> + if (!ret)
> + ret = iosf_mbi_pci_read_mdr(mcrx, mcr, mdr);
> + spin_unlock_irqrestore(&iosf_mbi_lock, flags);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(iosf_mbi_read_with_fid);
> +
> +int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 mdr)
> +{
> + u32 mcr, mcrx;
> + unsigned long flags;
> + int ret;
> +
> + /*Access to the GFX unit is handled by GPU code */

Ditto.

> + if (port == BT_MBI_UNIT_GFX) {
> + WARN_ON(1);
> + return -EPERM;
> + }
> +
> + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
> + mcrx = offset & MBI_MASK_HI;
> +
> + spin_lock_irqsave(&iosf_mbi_lock, flags);
> + ret = iosf_mbi_pci_write_fid(fid);
> + if (!ret)
> + ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr);
> + spin_unlock_irqrestore(&iosf_mbi_lock, flags);

Both of them quite similar to already exist _write()/_read(). Is it
possible to combine them out?

> +
> + return ret;
> +}
> +EXPORT_SYMBOL(iosf_mbi_write_with_fid);
> +
>  bool iosf_mbi_available(void)
>  {
>   /* Mbi isn't hot-pluggable. No remove routine is provided */

--
Andy Shevchenko <[email protected]>
Intel Finland Oy

2016-04-12 00:18:45

by Yang, Fei

[permalink] [raw]
Subject: RE: [PATCH] IOSF: Add interface for the cases requiring fid

> In subject better to use x86/platform/iosf_mbi prefix.
Will update commit message.

>> Some implementations may require an additional step for setting the
>> FID
> What FID stands for?
Function ID defined in IOSF specification. Will add more detail in the updated commit message.

>> Change-Id: Ic0227f9e74133a3203aa08e8471939f905d19622
> This should not be here.
Will remove

>> --- a/arch/x86/platform/intel/iosf_mbi.c
>> +++ b/arch/x86/platform/intel/iosf_mbi.c
>> @@ -98,6 +98,24 @@ fail_write:
>>   return result;
>>  }
>>  
>> +static int iosf_mbi_pci_write_fid(u32 fid)
> Function name should continue already used pattern, i.e.
> …_write_mcrp()
Will change.

>> +{
>> + int result;
>> +
>> + if (!mbi_pdev)
>> + return -ENODEV;
>> +


>> + result = pci_write_config_dword(mbi_pdev, MBI_MCRP_OFFSET,
>> fid);

> The function of one line.
> So, please, inline it directly where it's used.
Not sure I understand this one, do you meant something like this?
static inline int iosf_mbi_pci_write_fid(u32 fid)


>> +/*
>> + * Some IP blocks require fid to access their registers.
> Any user?
> This API doesn't make much sense without user.
The driver that uses this API is a DRM based display controller driver, which is not currently in the upstream.
But this API is a prerequisite of pushing the display driver upstream.


>> + * fid value is programmed through MCRP register, see above function
>> + * iosf_mbi_pci_write_fid() for details.
>> + */
>> +int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
>> u32 *mdr)
> Name kinda fuzzy. How user should know which one to choose? Does fid ==
> 0 work for some cases? We have to think about API and naming.
This is SoC dependent. The drivers accessing registers through IOSF sideband has to
know if fid is required.


>> + /*Access to the GFX unit is handled by GPU code */
> Spaces.
Will add.

>> + /*Access to the GFX unit is handled by GPU code */
> Ditto.
Will add.

>> + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
>> + mcrx = offset & MBI_MASK_HI;
>> +
>> + spin_lock_irqsave(&iosf_mbi_lock, flags);
>> + ret = iosf_mbi_pci_write_fid(fid);
>> + if (!ret)
>> + ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr);
>> + spin_unlock_irqrestore(&iosf_mbi_lock, flags);
> Both of them quite similar to already exist _write()/_read(). Is it possible to combine them out?
Trying to avoid modifying existing code that uses the _read/_write API.


2016-04-13 13:27:44

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH] IOSF: Add interface for the cases requiring fid

On Fri, 2016-04-08 at 14:02 -0700, Fei Yang wrote:
> From: Fei Yang <[email protected]>
>
> Some implementations may require an additional step for setting the
> FID
> bits to ensure correct transactions over the IOSF side band interface.
> Add the FID support accordingly for such implementations
>

Cc'ed to Ville to take a look.

As mentioned in a follow up the user of this is "a DRM based display
controller driver, which is not currently in the upstream.
But this API is a prerequisite of pushing the display driver upstream."

> Change-Id: Ic0227f9e74133a3203aa08e8471939f905d19622
> Signed-off-by: Fei Yang <[email protected]>
> ---
>  arch/x86/include/asm/iosf_mbi.h    | 27 ++++++++++++++
>  arch/x86/platform/intel/iosf_mbi.c | 73
> ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 100 insertions(+)
>
> diff --git a/arch/x86/include/asm/iosf_mbi.h
> b/arch/x86/include/asm/iosf_mbi.h
> index b41ee16..71511ba 100644
> --- a/arch/x86/include/asm/iosf_mbi.h
> +++ b/arch/x86/include/asm/iosf_mbi.h
> @@ -8,6 +8,7 @@
>  #define MBI_MCR_OFFSET 0xD0
>  #define MBI_MDR_OFFSET 0xD4
>  #define MBI_MCRX_OFFSET 0xD8
> +#define MBI_MCRP_OFFSET 0xDC
>  
>  #define MBI_RD_MASK 0xFEFFFFFF
>  #define MBI_WR_MASK 0X01000000
> @@ -88,6 +89,32 @@ int iosf_mbi_write(u8 port, u8 opcode, u32 offset,
> u32 mdr);
>   */
>  int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32
> mask);
>  
> +/**
> + * iosf_mbi_read_with_fid() - MailBox Interface read command
> requiring fid
> + * @fid: fid bits
> + * @port: port indicating subunit being accessed
> + * @opcode: port specific read or write opcode
> + * @offset: register address offset
> + * @mdr: register data to be read
> + *
> + * Locking is handled by spinlock - cannot sleep.
> + * Return: Nonzero on error
> + */
> +int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 *mdr);
> +
> +/**
> + * iosf_mbi_write_with_fid() - MailBox unmasked write command
> requiring fid
> + * @fid: fid bits
> + * @port: port indicating subunit being accessed
> + * @opcode: port specific read or write opcode
> + * @offset: register address offset
> + * @mdr: register data to be written
> + *
> + * Locking is handled by spinlock - cannot sleep.
> + * Return: Nonzero on error
> + */
> +int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 mdr);
> +
>  #else /* CONFIG_IOSF_MBI is not enabled */
>  static inline
>  bool iosf_mbi_available(void)
> diff --git a/arch/x86/platform/intel/iosf_mbi.c
> b/arch/x86/platform/intel/iosf_mbi.c
> index edf2c54..af182c1 100644
> --- a/arch/x86/platform/intel/iosf_mbi.c
> +++ b/arch/x86/platform/intel/iosf_mbi.c
> @@ -98,6 +98,24 @@ fail_write:
>   return result;
>  }
>  
> +static int iosf_mbi_pci_write_fid(u32 fid)
> +{
> + int result;
> +
> + if (!mbi_pdev)
> + return -ENODEV;
> +
> + result = pci_write_config_dword(mbi_pdev, MBI_MCRP_OFFSET,
> fid);
> + if (result < 0)
> + goto fail_fid_write;
> +
> + return 0;
> +
> +fail_fid_write:
> + dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n",
> result);
> + return result;
> +}
> +
>  int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr)
>  {
>   u32 mcr, mcrx;
> @@ -183,6 +201,61 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32
> offset, u32 mdr, u32 mask)
>  }
>  EXPORT_SYMBOL(iosf_mbi_modify);
>  
> +/*
> + * Some IP blocks require fid to access their registers.
> + * fid value is programmed through MCRP register, see above function
> + * iosf_mbi_pci_write_fid() for details.
> + */
> +int iosf_mbi_read_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 *mdr)
> +{
> + u32 mcr, mcrx;
> + unsigned long flags;
> + int ret;
> +
> + /*Access to the GFX unit is handled by GPU code */
> + if (port == BT_MBI_UNIT_GFX) {
> + WARN_ON(1);
> + return -EPERM;
> + }
> +
> + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
> + mcrx = offset & MBI_MASK_HI;
> +
> + spin_lock_irqsave(&iosf_mbi_lock, flags);
> + ret = iosf_mbi_pci_write_fid(fid);
> + if (!ret)
> + ret = iosf_mbi_pci_read_mdr(mcrx, mcr, mdr);
> + spin_unlock_irqrestore(&iosf_mbi_lock, flags);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(iosf_mbi_read_with_fid);
> +
> +int iosf_mbi_write_with_fid(u32 fid, u8 port, u8 opcode, u32 offset,
> u32 mdr)
> +{
> + u32 mcr, mcrx;
> + unsigned long flags;
> + int ret;
> +
> + /*Access to the GFX unit is handled by GPU code */
> + if (port == BT_MBI_UNIT_GFX) {
> + WARN_ON(1);
> + return -EPERM;
> + }
> +
> + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO);
> + mcrx = offset & MBI_MASK_HI;
> +
> + spin_lock_irqsave(&iosf_mbi_lock, flags);
> + ret = iosf_mbi_pci_write_fid(fid);
> + if (!ret)
> + ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr);
> + spin_unlock_irqrestore(&iosf_mbi_lock, flags);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(iosf_mbi_write_with_fid);
> +
>  bool iosf_mbi_available(void)
>  {
>   /* Mbi isn't hot-pluggable. No remove routine is provided */

--
Andy Shevchenko <[email protected]>
Intel Finland Oy