[RFC PATCH 0/2] vlynq: remove bus support

[RFC PATCH 0/2] vlynq: remove bus support

[Wolfram Sang]

From: Wolfram Sang <wsa+renesas@sang-engineering.com>

I'd like to clean up the 'drivers' directory and Kconfig menu, at least
a little. One major thing I noticed is that VLYNQ can actually be
removed. From patch 2:

---
There are no users with a vlynq_driver in the Kernel tree. So, remove
the bus driver which hardly has seen any activity since 2009. It was
even marked EXPERIMENTAL as long as that symbol existed. OpenWRT had
some out-of-tree drivers which they probably intended to upport, but AR7
devices are not supported anymore because they are "stuck with Kernel
3.18" [1]. So, this code can go nowadays.

[1] https://openwrt.org/docs/techref/targets/ar7
---

Patch 1 removes MIPS specific bus initialization code which is the only
user of the VLYNQ bus currently.

Sending out as RFC to gather comments. Patches are based on 6.6-rc1 and
created with "--irreversible-delete" to save some space. They are
compile tested only, buildbots were happy.

I think this mainly goes to Florian Fainelli. Florian, what do you
think?

All the best!

   Wolfram


Wolfram Sang (2):
  MIPS: AR7: remove VLYNQ init
  vlynq: remove bus driver

 MAINTAINERS                          |   7 -
 arch/mips/Kconfig                    |   1 -
 arch/mips/ar7/platform.c             | 193 +------
 arch/mips/include/asm/mach-ar7/ar7.h |   1 -
 drivers/Kconfig                      |   2 -
 drivers/Makefile                     |   1 -
 drivers/vlynq/Kconfig                |  21 -
 drivers/vlynq/Makefile               |   6 -
 drivers/vlynq/vlynq.c                | 799 ---------------------------
 include/linux/vlynq.h                | 149 -----
 10 files changed, 1 insertion(+), 1179 deletions(-)
 delete mode 100644 drivers/vlynq/Kconfig
 delete mode 100644 drivers/vlynq/Makefile
 delete mode 100644 drivers/vlynq/vlynq.c
 delete mode 100644 include/linux/vlynq.h

-- 
2.35.1

[RFC PATCH 1/2] MIPS: AR7: remove VLYNQ init

[Wolfram Sang]

From: Wolfram Sang <wsa+renesas@sang-engineering.com>

VLYNQ bus support is going to be removed from the Kernel because there
has never been a vlynq_driver in the tree since 2009. So, it doesn't
make sense to setup a bus controller when it is not going to be
accessed. Remove the VLYNQ init code to remove the bus driver later.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 arch/mips/Kconfig                    |   1 -
 arch/mips/ar7/platform.c             | 193 +--------------------------
 arch/mips/include/asm/mach-ar7/ar7.h |   1 -
 3 files changed, 1 insertion(+), 194 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index bc8421859006..0e8aff7355fb 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -219,7 +219,6 @@ config AR7
 	select SYS_SUPPORTS_MIPS16
 	select SYS_SUPPORTS_ZBOOT_UART16550
 	select GPIOLIB
-	select VLYNQ
 	help
 	  Support for the Texas Instruments AR7 System-on-a-Chip
 	  family: TNETD7100, 7200 and 7300.
diff --git a/arch/mips/ar7/platform.c b/arch/mips/ar7/platform.c
index 215149a85d83..b23dd74ca40e 100644
--- a/arch/mips/ar7/platform.c
+++ b/arch/mips/ar7/platform.c
@@ -14,7 +14,6 @@
 #include <linux/serial_8250.h>
 #include <linux/ioport.h>
 #include <linux/io.h>
-#include <linux/vlynq.h>
 #include <linux/leds.h>
 #include <linux/string.h>
 #include <linux/etherdevice.h>
@@ -27,156 +26,6 @@
 #include <asm/mach-ar7/ar7.h>
 #include <asm/mach-ar7/prom.h>
 
-/*****************************************************************************
- * VLYNQ Bus
- ****************************************************************************/
-struct plat_vlynq_data {
-	struct plat_vlynq_ops ops;
-	int gpio_bit;
-	int reset_bit;
-};
-
-static int vlynq_on(struct vlynq_device *dev)
-{
-	int ret;
-	struct plat_vlynq_data *pdata = dev->dev.platform_data;
-
-	ret = gpio_request(pdata->gpio_bit, "vlynq");
-	if (ret)
-		goto out;
-
-	ar7_device_reset(pdata->reset_bit);
-
-	ret = ar7_gpio_disable(pdata->gpio_bit);
-	if (ret)
-		goto out_enabled;
-
-	ret = ar7_gpio_enable(pdata->gpio_bit);
-	if (ret)
-		goto out_enabled;
-
-	ret = gpio_direction_output(pdata->gpio_bit, 0);
-	if (ret)
-		goto out_gpio_enabled;
-
-	msleep(50);
-
-	gpio_set_value(pdata->gpio_bit, 1);
-
-	msleep(50);
-
-	return 0;
-
-out_gpio_enabled:
-	ar7_gpio_disable(pdata->gpio_bit);
-out_enabled:
-	ar7_device_disable(pdata->reset_bit);
-	gpio_free(pdata->gpio_bit);
-out:
-	return ret;
-}
-
-static void vlynq_off(struct vlynq_device *dev)
-{
-	struct plat_vlynq_data *pdata = dev->dev.platform_data;
-
-	ar7_gpio_disable(pdata->gpio_bit);
-	gpio_free(pdata->gpio_bit);
-	ar7_device_disable(pdata->reset_bit);
-}
-
-static struct resource vlynq_low_res[] = {
-	{
-		.name	= "regs",
-		.flags	= IORESOURCE_MEM,
-		.start	= AR7_REGS_VLYNQ0,
-		.end	= AR7_REGS_VLYNQ0 + 0xff,
-	},
-	{
-		.name	= "irq",
-		.flags	= IORESOURCE_IRQ,
-		.start	= 29,
-		.end	= 29,
-	},
-	{
-		.name	= "mem",
-		.flags	= IORESOURCE_MEM,
-		.start	= 0x04000000,
-		.end	= 0x04ffffff,
-	},
-	{
-		.name	= "devirq",
-		.flags	= IORESOURCE_IRQ,
-		.start	= 80,
-		.end	= 111,
-	},
-};
-
-static struct resource vlynq_high_res[] = {
-	{
-		.name	= "regs",
-		.flags	= IORESOURCE_MEM,
-		.start	= AR7_REGS_VLYNQ1,
-		.end	= AR7_REGS_VLYNQ1 + 0xff,
-	},
-	{
-		.name	= "irq",
-		.flags	= IORESOURCE_IRQ,
-		.start	= 33,
-		.end	= 33,
-	},
-	{
-		.name	= "mem",
-		.flags	= IORESOURCE_MEM,
-		.start	= 0x0c000000,
-		.end	= 0x0cffffff,
-	},
-	{
-		.name	= "devirq",
-		.flags	= IORESOURCE_IRQ,
-		.start	= 112,
-		.end	= 143,
-	},
-};
-
-static struct plat_vlynq_data vlynq_low_data = {
-	.ops = {
-		.on	= vlynq_on,
-		.off	= vlynq_off,
-	},
-	.reset_bit	= 20,
-	.gpio_bit	= 18,
-};
-
-static struct plat_vlynq_data vlynq_high_data = {
-	.ops = {
-		.on	= vlynq_on,
-		.off	= vlynq_off,
-	},
-	.reset_bit	= 16,
-	.gpio_bit	= 19,
-};
-
-static struct platform_device vlynq_low = {
-	.id		= 0,
-	.name		= "vlynq",
-	.dev = {
-		.platform_data	= &vlynq_low_data,
-	},
-	.resource	= vlynq_low_res,
-	.num_resources	= ARRAY_SIZE(vlynq_low_res),
-};
-
-static struct platform_device vlynq_high = {
-	.id		= 1,
-	.name		= "vlynq",
-	.dev = {
-		.platform_data	= &vlynq_high_data,
-	},
-	.resource	= vlynq_high_res,
-	.num_resources	= ARRAY_SIZE(vlynq_high_res),
-};
-
 /*****************************************************************************
  * Flash
  ****************************************************************************/
@@ -592,34 +441,6 @@ static int __init ar7_register_uarts(void)
 
 static void __init titan_fixup_devices(void)
 {
-	/* Set vlynq0 data */
-	vlynq_low_data.reset_bit = 15;
-	vlynq_low_data.gpio_bit = 14;
-
-	/* Set vlynq1 data */
-	vlynq_high_data.reset_bit = 16;
-	vlynq_high_data.gpio_bit = 7;
-
-	/* Set vlynq0 resources */
-	vlynq_low_res[0].start = TITAN_REGS_VLYNQ0;
-	vlynq_low_res[0].end = TITAN_REGS_VLYNQ0 + 0xff;
-	vlynq_low_res[1].start = 33;
-	vlynq_low_res[1].end = 33;
-	vlynq_low_res[2].start = 0x0c000000;
-	vlynq_low_res[2].end = 0x0fffffff;
-	vlynq_low_res[3].start = 80;
-	vlynq_low_res[3].end = 111;
-
-	/* Set vlynq1 resources */
-	vlynq_high_res[0].start = TITAN_REGS_VLYNQ1;
-	vlynq_high_res[0].end = TITAN_REGS_VLYNQ1 + 0xff;
-	vlynq_high_res[1].start = 34;
-	vlynq_high_res[1].end = 34;
-	vlynq_high_res[2].start = 0x40000000;
-	vlynq_high_res[2].end = 0x43ffffff;
-	vlynq_high_res[3].start = 112;
-	vlynq_high_res[3].end = 143;
-
 	/* Set cpmac0 data */
 	cpmac_low_data.phy_mask = 0x40000000;
 
@@ -656,18 +477,6 @@ static int __init ar7_register_devices(void)
 	if (ar7_is_titan())
 		titan_fixup_devices();
 
-	ar7_device_disable(vlynq_low_data.reset_bit);
-	res = platform_device_register(&vlynq_low);
-	if (res)
-		pr_warn("unable to register vlynq-low: %d\n", res);
-
-	if (ar7_has_high_vlynq()) {
-		ar7_device_disable(vlynq_high_data.reset_bit);
-		res = platform_device_register(&vlynq_high);
-		if (res)
-			pr_warn("unable to register vlynq-high: %d\n", res);
-	}
-
 	if (ar7_has_high_cpmac()) {
 		res = fixed_phy_add(PHY_POLL, cpmac_high.id,
 				    &fixed_phy_status);
@@ -706,7 +515,7 @@ static int __init ar7_register_devices(void)
 	val = readl(bootcr);
 	iounmap(bootcr);
 	if (val & AR7_WDT_HW_ENA) {
-		if (ar7_has_high_vlynq())
+		if (ar7_has_high_cpmac())
 			ar7_wdt_res.start = UR8_REGS_WDT;
 		else
 			ar7_wdt_res.start = AR7_REGS_WDT;
diff --git a/arch/mips/include/asm/mach-ar7/ar7.h b/arch/mips/include/asm/mach-ar7/ar7.h
index 1e8621a6afa3..faa6a15503d6 100644
--- a/arch/mips/include/asm/mach-ar7/ar7.h
+++ b/arch/mips/include/asm/mach-ar7/ar7.h
@@ -142,7 +142,6 @@ static inline int ar7_has_high_cpmac(void)
 		return -ENXIO;
 	}
 }
-#define ar7_has_high_vlynq ar7_has_high_cpmac
 #define ar7_has_second_uart ar7_has_high_cpmac
 
 static inline void ar7_device_enable(u32 bit)
-- 
2.35.1

Re: [RFC PATCH 0/2] vlynq: remove bus support

[Jonas Gorski]

On Sat, 16 Sept 2023 at 11:18, Wolfram Sang <wsa@kernel.org> wrote:
>
> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
>
> I'd like to clean up the 'drivers' directory and Kconfig menu, at least
> a little. One major thing I noticed is that VLYNQ can actually be
> removed. From patch 2:
>
> ---
> There are no users with a vlynq_driver in the Kernel tree. So, remove
> the bus driver which hardly has seen any activity since 2009. It was
> even marked EXPERIMENTAL as long as that symbol existed. OpenWRT had
> some out-of-tree drivers which they probably intended to upport, but AR7
> devices are not supported anymore because they are "stuck with Kernel
> 3.18" [1]. So, this code can go nowadays.
>
> [1] https://openwrt.org/docs/techref/targets/ar7
> ---
>
> Patch 1 removes MIPS specific bus initialization code which is the only
> user of the VLYNQ bus currently.
>
> Sending out as RFC to gather comments. Patches are based on 6.6-rc1 and
> created with "--irreversible-delete" to save some space. They are
> compile tested only, buildbots were happy.
>
> I think this mainly goes to Florian Fainelli. Florian, what do you
> think?

I'm not Florian, but I worked a bit with AR7 as well, and going
through the (previously) supported/known devices they topped out at 8
MiB Flash and 32 MiB RAM, which isn't enough to run any reasonably
modern OpenWrt even if one would be willing to re-add support for it.

So from my perspective I suggest even dropping the AR7 code entirely.
I seriously doubt anyone is running a modern kernel on that.

Best Regards,
Jonas

Re: [RFC PATCH 0/2] vlynq: remove bus support

[Florian Fainelli]

On 9/16/2023 4:11 AM, Jonas Gorski wrote:
> On Sat, 16 Sept 2023 at 11:18, Wolfram Sang <wsa@kernel.org> wrote:
>>
>> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
>>
>> I'd like to clean up the 'drivers' directory and Kconfig menu, at least
>> a little. One major thing I noticed is that VLYNQ can actually be
>> removed. From patch 2:
>>
>> ---
>> There are no users with a vlynq_driver in the Kernel tree. So, remove
>> the bus driver which hardly has seen any activity since 2009. It was
>> even marked EXPERIMENTAL as long as that symbol existed. OpenWRT had
>> some out-of-tree drivers which they probably intended to upport, but AR7
>> devices are not supported anymore because they are "stuck with Kernel
>> 3.18" [1]. So, this code can go nowadays.
>>
>> [1] https://openwrt.org/docs/techref/targets/ar7
>> ---
>>
>> Patch 1 removes MIPS specific bus initialization code which is the only
>> user of the VLYNQ bus currently.
>>
>> Sending out as RFC to gather comments. Patches are based on 6.6-rc1 and
>> created with "--irreversible-delete" to save some space. They are
>> compile tested only, buildbots were happy.
>>
>> I think this mainly goes to Florian Fainelli. Florian, what do you
>> think?
> 
> I'm not Florian, but I worked a bit with AR7 as well, and going
> through the (previously) supported/known devices they topped out at 8
> MiB Flash and 32 MiB RAM, which isn't enough to run any reasonably
> modern OpenWrt even if one would be willing to re-add support for it.
> 
> So from my perspective I suggest even dropping the AR7 code entirely.
> I seriously doubt anyone is running a modern kernel on that.

Agreed, TI AR7 is nearly 25 years old now, we should be able to remove 
that. Wolfram, do you feel like doing that or would you rather have me 
do it, say next week?
-- 
Florian

Re: [RFC PATCH 0/2] vlynq: remove bus support

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 222 bytes --]


> Agreed, TI AR7 is nearly 25 years old now, we should be able to remove that.
> Wolfram, do you feel like doing that or would you rather have me do it, say
> next week?

I will try it, thanks for the heads up everyone!


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Re: [RFC PATCH 0/2] vlynq: remove bus support

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 580 bytes --]

Hi all,

> Agreed, TI AR7 is nearly 25 years old now, we should be able to remove that.
> Wolfram, do you feel like doing that or would you rather have me do it, say
> next week?

So, I pushed out an RC here:

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/cleanup/remove_ar7

Just waiting for the buildbot report before I send out patches. buildbot
was already happy with my protoype, though. But I needed to reorder the
patches. (I do wonder, though, if they build AR7. I would have expected
a build failure with my prototype).

Happy hacking,

   Wolfram


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Re: [RFC PATCH 0/2] vlynq: remove bus support

[Florian Fainelli]

On 9/18/23 06:18, Wolfram Sang wrote:
> Hi all,
> 
>> Agreed, TI AR7 is nearly 25 years old now, we should be able to remove that.
>> Wolfram, do you feel like doing that or would you rather have me do it, say
>> next week?
> 
> So, I pushed out an RC here:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/cleanup/remove_ar7
> 
> Just waiting for the buildbot report before I send out patches. buildbot
> was already happy with my protoype, though. But I needed to reorder the
> patches. (I do wonder, though, if they build AR7. I would have expected
> a build failure with my prototype).

Looks good to me, just a few nits:

arch/arm/configs/pxa_defconfig:CONFIG_MTD_AR7_PARTS=m

this is clearly a stray reference to begin with, but should be folded in 
your commit removing the MTD partition parser.

Other than that, LGTM and thanks for doing that clean up.
-- 
Florian

Re: [RFC PATCH 0/2] vlynq: remove bus support

[Wolfram Sang]

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Hi Florian,

> arch/arm/configs/pxa_defconfig:CONFIG_MTD_AR7_PARTS=m

Thanks, I removed this line as well.

> Other than that, LGTM and thanks for doing that clean up.

Cool, thanks for the review!

Happy hacking,

   Wolfram


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Re: [RFC PATCH 0/2] vlynq: remove bus support

[Greg KH]

On Sat, Sep 16, 2023 at 11:11:22AM +0200, Wolfram Sang wrote:
> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
> 
> I'd like to clean up the 'drivers' directory and Kconfig menu, at least
> a little. One major thing I noticed is that VLYNQ can actually be
> removed. From patch 2:
> 
> ---
> There are no users with a vlynq_driver in the Kernel tree. So, remove
> the bus driver which hardly has seen any activity since 2009. It was
> even marked EXPERIMENTAL as long as that symbol existed. OpenWRT had
> some out-of-tree drivers which they probably intended to upport, but AR7
> devices are not supported anymore because they are "stuck with Kernel
> 3.18" [1]. So, this code can go nowadays.
> 
> [1] https://openwrt.org/docs/techref/targets/ar7
> ---
> 
> Patch 1 removes MIPS specific bus initialization code which is the only
> user of the VLYNQ bus currently.
> 
> Sending out as RFC to gather comments. Patches are based on 6.6-rc1 and
> created with "--irreversible-delete" to save some space. They are
> compile tested only, buildbots were happy.
> 
> I think this mainly goes to Florian Fainelli. Florian, what do you
> think?

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>