diff mbox series

[v1,7/7] i2c: i801: convert to use common P2SB accessor

Message ID 20210308122020.57071-8-andriy.shevchenko@linux.intel.com
State New
Headers show
Series PCI: introduce p2sb helper | expand

Commit Message

Andy Shevchenko March 8, 2021, 12:20 p.m. UTC
Since we have a common P2SB accessor in tree we may use it instead of
open coded variants.

Replace custom code by pci_p2sb_bar() call.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/busses/Kconfig    |  1 +
 drivers/i2c/busses/i2c-i801.c | 40 ++++++++---------------------------
 drivers/pci/pci-p2sb.c        |  6 ++++++
 3 files changed, 16 insertions(+), 31 deletions(-)

Comments

Jean Delvare March 10, 2021, 2:51 p.m. UTC | #1
Hi Andy,

On Mon,  8 Mar 2021 14:20:20 +0200, Andy Shevchenko wrote:
> Since we have a common P2SB accessor in tree we may use it instead of

> open coded variants.

> 

> Replace custom code by pci_p2sb_bar() call.


I like the idea. Just two things...

> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> ---

>  drivers/i2c/busses/Kconfig    |  1 +

>  drivers/i2c/busses/i2c-i801.c | 40 ++++++++---------------------------

>  drivers/pci/pci-p2sb.c        |  6 ++++++

>  3 files changed, 16 insertions(+), 31 deletions(-)

> 

> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig

> index 05ebf7546e3f..ffd3007f888c 100644

> --- a/drivers/i2c/busses/Kconfig

> +++ b/drivers/i2c/busses/Kconfig

> @@ -101,6 +101,7 @@ config I2C_HIX5HD2

>  config I2C_I801

>  	tristate "Intel 82801 (ICH/PCH)"

>  	depends on PCI

> +	select PCI_P2SB if X86

>  	select CHECK_SIGNATURE if X86 && DMI

>  	select I2C_SMBUS

>  	help

> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c

> index 4acee6f9e5a3..23b43de9786a 100644

> --- a/drivers/i2c/busses/i2c-i801.c

> +++ b/drivers/i2c/busses/i2c-i801.c

> @@ -90,6 +90,7 @@

>  #include <linux/interrupt.h>

>  #include <linux/module.h>

>  #include <linux/pci.h>

> +#include <linux/pci-p2sb.h>

>  #include <linux/kernel.h>

>  #include <linux/stddef.h>

>  #include <linux/delay.h>

> @@ -136,7 +137,6 @@

>  #define TCOBASE		0x050

>  #define TCOCTL		0x054

>  

> -#define SBREG_BAR		0x10

>  #define SBREG_SMBCTRL		0xc6000c

>  #define SBREG_SMBCTRL_DNV	0xcf000c

>  

> @@ -1524,52 +1524,30 @@ static const struct itco_wdt_platform_data spt_tco_platform_data = {

>  	.version = 4,

>  };

>  

> -static DEFINE_SPINLOCK(p2sb_spinlock);

> -

>  static struct platform_device *

>  i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev,

>  		 struct resource *tco_res)

>  {

>  	struct resource *res;

>  	unsigned int devfn;

> -	u64 base64_addr;

> -	u32 base_addr;

> -	u8 hidden;

> +	int ret;

>  

>  	/*

>  	 * We must access the NO_REBOOT bit over the Primary to Sideband

> -	 * bridge (P2SB). The BIOS prevents the P2SB device from being

> -	 * enumerated by the PCI subsystem, so we need to unhide/hide it

> -	 * to lookup the P2SB BAR.

> +	 * bridge (P2SB).

>  	 */

> -	spin_lock(&p2sb_spinlock);

>  

>  	devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1);

>  

> -	/* Unhide the P2SB device, if it is hidden */

> -	pci_bus_read_config_byte(pci_dev->bus, devfn, 0xe1, &hidden);

> -	if (hidden)

> -		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0);

> -

> -	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR, &base_addr);

> -	base64_addr = base_addr & 0xfffffff0;

> -

> -	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR + 0x4, &base_addr);

> -	base64_addr |= (u64)base_addr << 32;

> -

> -	/* Hide the P2SB device, if it was hidden before */

> -	if (hidden)

> -		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden);

> -	spin_unlock(&p2sb_spinlock);

> -

>  	res = &tco_res[1];

> +	ret = pci_p2sb_bar(pci_dev, devfn, res);

> +	if (ret)

> +		return ERR_PTR(ret);

> +

>  	if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS)

> -		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL_DNV;

> +		res->start += SBREG_SMBCTRL_DNV;

>  	else

> -		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL;

> -

> -	res->end = res->start + 3;

> -	res->flags = IORESOURCE_MEM;

> +		res->start += SBREG_SMBCTRL;


I can't see why you no longer set res->end and res->flags here. I can
imagine that pci_p2sb_bar() may have set the flags for us, but not that
->end is still correct after you fixed up ->start. Am I missing
something?

>  

>  	return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1,

>  					tco_res, 2, &spt_tco_platform_data,

> diff --git a/drivers/pci/pci-p2sb.c b/drivers/pci/pci-p2sb.c

> index 68d7dad48cdb..7f6bc7d4482a 100644

> --- a/drivers/pci/pci-p2sb.c

> +++ b/drivers/pci/pci-p2sb.c

> @@ -22,6 +22,12 @@

>  

>  static const struct x86_cpu_id p2sb_cpu_ids[] = {

>  	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	PCI_DEVFN(13, 0)),

> +	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	PCI_DEVFN(31, 1)),

> +	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,	PCI_DEVFN(31, 1)),

> +	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		PCI_DEVFN(31, 1)),

> +	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		PCI_DEVFN(31, 1)),

> +	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		PCI_DEVFN(31, 1)),

> +	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		PCI_DEVFN(31, 1)),

>  	{}

>  };

>  


Any reason why this is added in this patch instead of [3/7] (PCI: New
Primary to Sideband (P2SB) bridge support library)?

-- 
Jean Delvare
SUSE L3 Support
Andy Shevchenko Dec. 21, 2021, 3:08 p.m. UTC | #2
On Wed, Mar 10, 2021 at 03:51:45PM +0100, Jean Delvare wrote:
> On Mon,  8 Mar 2021 14:20:20 +0200, Andy Shevchenko wrote:

...

> > -	res->end = res->start + 3;
> > -	res->flags = IORESOURCE_MEM;
> > +		res->start += SBREG_SMBCTRL;
> 
> I can't see why you no longer set res->end and res->flags here. I can
> imagine that pci_p2sb_bar() may have set the flags for us, but not that
> ->end is still correct after you fixed up ->start. Am I missing
> something?

Good catch of the res->end! But flags actually may be MEM64, which the
original code doesn't properly handle.

...

> >  static const struct x86_cpu_id p2sb_cpu_ids[] = {
> >  	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	PCI_DEVFN(13, 0)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	PCI_DEVFN(31, 1)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,	PCI_DEVFN(31, 1)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		PCI_DEVFN(31, 1)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		PCI_DEVFN(31, 1)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		PCI_DEVFN(31, 1)),
> > +	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		PCI_DEVFN(31, 1)),
> >  	{}
> >  };
> 
> Any reason why this is added in this patch instead of [3/7] (PCI: New
> Primary to Sideband (P2SB) bridge support library)?

Filling this on demand, no user no entry. I think it's how we assume the code
to be applied in the kernel.
diff mbox series

Patch

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 05ebf7546e3f..ffd3007f888c 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -101,6 +101,7 @@  config I2C_HIX5HD2
 config I2C_I801
 	tristate "Intel 82801 (ICH/PCH)"
 	depends on PCI
+	select PCI_P2SB if X86
 	select CHECK_SIGNATURE if X86 && DMI
 	select I2C_SMBUS
 	help
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 4acee6f9e5a3..23b43de9786a 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -90,6 +90,7 @@ 
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/pci-p2sb.h>
 #include <linux/kernel.h>
 #include <linux/stddef.h>
 #include <linux/delay.h>
@@ -136,7 +137,6 @@ 
 #define TCOBASE		0x050
 #define TCOCTL		0x054
 
-#define SBREG_BAR		0x10
 #define SBREG_SMBCTRL		0xc6000c
 #define SBREG_SMBCTRL_DNV	0xcf000c
 
@@ -1524,52 +1524,30 @@  static const struct itco_wdt_platform_data spt_tco_platform_data = {
 	.version = 4,
 };
 
-static DEFINE_SPINLOCK(p2sb_spinlock);
-
 static struct platform_device *
 i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev,
 		 struct resource *tco_res)
 {
 	struct resource *res;
 	unsigned int devfn;
-	u64 base64_addr;
-	u32 base_addr;
-	u8 hidden;
+	int ret;
 
 	/*
 	 * We must access the NO_REBOOT bit over the Primary to Sideband
-	 * bridge (P2SB). The BIOS prevents the P2SB device from being
-	 * enumerated by the PCI subsystem, so we need to unhide/hide it
-	 * to lookup the P2SB BAR.
+	 * bridge (P2SB).
 	 */
-	spin_lock(&p2sb_spinlock);
 
 	devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1);
 
-	/* Unhide the P2SB device, if it is hidden */
-	pci_bus_read_config_byte(pci_dev->bus, devfn, 0xe1, &hidden);
-	if (hidden)
-		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0);
-
-	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR, &base_addr);
-	base64_addr = base_addr & 0xfffffff0;
-
-	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR + 0x4, &base_addr);
-	base64_addr |= (u64)base_addr << 32;
-
-	/* Hide the P2SB device, if it was hidden before */
-	if (hidden)
-		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden);
-	spin_unlock(&p2sb_spinlock);
-
 	res = &tco_res[1];
+	ret = pci_p2sb_bar(pci_dev, devfn, res);
+	if (ret)
+		return ERR_PTR(ret);
+
 	if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS)
-		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL_DNV;
+		res->start += SBREG_SMBCTRL_DNV;
 	else
-		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL;
-
-	res->end = res->start + 3;
-	res->flags = IORESOURCE_MEM;
+		res->start += SBREG_SMBCTRL;
 
 	return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1,
 					tco_res, 2, &spt_tco_platform_data,
diff --git a/drivers/pci/pci-p2sb.c b/drivers/pci/pci-p2sb.c
index 68d7dad48cdb..7f6bc7d4482a 100644
--- a/drivers/pci/pci-p2sb.c
+++ b/drivers/pci/pci-p2sb.c
@@ -22,6 +22,12 @@ 
 
 static const struct x86_cpu_id p2sb_cpu_ids[] = {
 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	PCI_DEVFN(13, 0)),
+	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	PCI_DEVFN(31, 1)),
+	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,	PCI_DEVFN(31, 1)),
+	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,		PCI_DEVFN(31, 1)),
+	X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,		PCI_DEVFN(31, 1)),
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,		PCI_DEVFN(31, 1)),
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,		PCI_DEVFN(31, 1)),
 	{}
 };