[PATCH net-next 1/6] net: stmmac: add platform library

[PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

Add a platform library of helper functions for common traits in the
platform drivers. Currently, this is setting the tx clock.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
 .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
 .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
 3 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h

diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index 5b57aee19267..ba2cbfa0c9d1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -6,7 +6,7 @@ stmmac-objs:= stmmac_main.o stmmac_ethtool.o stmmac_mdio.o ring_mode.o	\
 	      mmc_core.o stmmac_hwtstamp.o stmmac_ptp.o dwmac4_descs.o	\
 	      dwmac4_dma.o dwmac4_lib.o dwmac4_core.o dwmac5.o hwif.o \
 	      stmmac_tc.o dwxgmac2_core.o dwxgmac2_dma.o dwxgmac2_descs.o \
-	      stmmac_xdp.o \
+	      stmmac_xdp.o stmmac_plat_lib.o \
 	      $(stmmac-y)
 
 stmmac-$(CONFIG_STMMAC_SELFTESTS) += stmmac_selftests.o
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
new file mode 100644
index 000000000000..abb9f512bb0e
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
@@ -0,0 +1,29 @@
+#include <linux/stmmac.h>
+#include <linux/clk.h>
+
+#include "stmmac_plat_lib.h"
+
+int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed)
+{
+	unsigned long rate;
+
+	switch (speed) {
+	case SPEED_1000:
+		rate = 125000000;
+		break;
+
+	case SPEED_100:
+		rate = 25000000;
+		break;
+
+	case SPEED_10:
+		rate = 2500000;
+		break;
+
+	default:
+		return -ENOTSUPP;
+	}
+
+	return clk_set_rate(tx_clk, rate);
+}
+EXPORT_SYMBOL_GPL(dwmac_set_tx_clk_gmii);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h
new file mode 100644
index 000000000000..926fdce379b3
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h
@@ -0,0 +1,8 @@
+#ifndef STMMAC_PLAT_LIB_H
+#define STMMAC_PLAT_LIB_H
+
+struct clk;
+
+int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed);
+
+#endif
-- 
2.30.2

RE: [PATCH net-next 1/6] net: stmmac: add platform library

[Jose Abreu]

From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Date: Mon, Sep 11, 2023 at 16:28:40

> Add a platform library of helper functions for common traits in the
> platform drivers. Currently, this is setting the tx clock.
> 
> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> ---
>  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
>  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
>  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++

Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
more helpers on the future that are not only for platform-based drivers?

I believe it's also missing the SPDX identifiers?

Thanks,
Jose

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Serge Semin]

On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> Date: Mon, Sep 11, 2023 at 16:28:40
> 
> > Add a platform library of helper functions for common traits in the
> > platform drivers. Currently, this is setting the tx clock.
> > 
> > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > ---

> >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> 
> Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> more helpers on the future that are not only for platform-based drivers?

What is the difference between stmmac_platform.{c,h} and
stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
may cause confusions like mixed definitions in both of these files.

Why not to use the stmmac_platform.{c,h} instead of adding one more
file? Especially seeing it already has some generic
platform/glue-drivers helpers like:
stmmac_get_platform_resources() <- especially this one.
(devm_)stmmac_probe_config_dt()
stmmac_remove_config_dt()
stmmac_pltfr_init()
stmmac_pltfr_exit()
(devm_)stmmac_pltfr_probe()
stmmac_pltfr_remove()
stmmac_pltfr_suspend()
stmmac_pltfr_resume()
stmmac_runtime_suspend()
stmmac_runtime_resume()
stmmac_pltfr_noirq_suspend()
stmmac_pltfr_noirq_resume()
All of them look like being decent to be defined in the generic
platform library methods too.

-Serge(y)

> 
> I believe it's also missing the SPDX identifiers?
> 
> Thanks,
> Jose

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > Date: Mon, Sep 11, 2023 at 16:28:40
> > 
> > > Add a platform library of helper functions for common traits in the
> > > platform drivers. Currently, this is setting the tx clock.
> > > 
> > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > ---
> 
> > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > 
> > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > more helpers on the future that are not only for platform-based drivers?
> 
> What is the difference between stmmac_platform.{c,h} and
> stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> may cause confusions like mixed definitions in both of these files.
> 
> Why not to use the stmmac_platform.{c,h} instead of adding one more
> file?

Is stmmac_platform.{c,h} used by all the drivers that are making use of
this? I'm not entirely sure.

If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
onto drivers that only want to use this one function.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Serge Semin]

On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > 
> > > > Add a platform library of helper functions for common traits in the
> > > > platform drivers. Currently, this is setting the tx clock.
> > > > 
> > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > ---
> > 
> > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > 
> > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > more helpers on the future that are not only for platform-based drivers?
> > 
> > What is the difference between stmmac_platform.{c,h} and
> > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > may cause confusions like mixed definitions in both of these files.
> > 
> > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > file?
> 

> Is stmmac_platform.{c,h} used by all the drivers that are making use of
> this? I'm not entirely sure.
> 
> If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> onto drivers that only want to use this one function.

With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
the methods from the stmmac_platform.c module including the bits
touched by your patchset. AFAICS semantically both stmmac_platform.c
and stmmac_plat_lib.c look the same. They don't do anything on its own
but provide some common methods utilized by the glue drivers for some
platform-specific setups. So basically stmmac_platform.[ch] is already
a library of the common platform methods. There is no need in creating
another one.

-Serge(y)

> 
> -- 
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

On Wed, Sep 13, 2023 at 03:56:07AM +0300, Serge Semin wrote:
> On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> > On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > > 
> > > > > Add a platform library of helper functions for common traits in the
> > > > > platform drivers. Currently, this is setting the tx clock.
> > > > > 
> > > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > ---
> > > 
> > > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > > 
> > > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > > more helpers on the future that are not only for platform-based drivers?
> > > 
> > > What is the difference between stmmac_platform.{c,h} and
> > > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > > may cause confusions like mixed definitions in both of these files.
> > > 
> > > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > > file?
> > 
> 
> > Is stmmac_platform.{c,h} used by all the drivers that are making use of
> > this? I'm not entirely sure.
> > 
> > If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> > don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> > onto drivers that only want to use this one function.
> 
> With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
> the methods from the stmmac_platform.c module including the bits
> touched by your patchset. AFAICS semantically both stmmac_platform.c
> and stmmac_plat_lib.c look the same. They don't do anything on its own
> but provide some common methods utilized by the glue drivers for some
> platform-specific setups. So basically stmmac_platform.[ch] is already
> a library of the common platform methods. There is no need in creating
> another one.

I'm not questioning whether it should be merged, I'm questioning whether
all drivers that I'm touching make use of stmmac_platform.c, so your
long winded answer was entirely unnecessary. All you needed to do was
answer the question I asked, rather than teach me how to suck eggs.

Thanks.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

On Wed, Sep 13, 2023 at 03:14:47PM +0100, Russell King (Oracle) wrote:
> On Wed, Sep 13, 2023 at 03:56:07AM +0300, Serge Semin wrote:
> > On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> > > On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > > > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > > > 
> > > > > > Add a platform library of helper functions for common traits in the
> > > > > > platform drivers. Currently, this is setting the tx clock.
> > > > > > 
> > > > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > ---
> > > > 
> > > > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > > > 
> > > > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > > > more helpers on the future that are not only for platform-based drivers?
> > > > 
> > > > What is the difference between stmmac_platform.{c,h} and
> > > > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > > > may cause confusions like mixed definitions in both of these files.
> > > > 
> > > > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > > > file?
> > > 
> > 
> > > Is stmmac_platform.{c,h} used by all the drivers that are making use of
> > > this? I'm not entirely sure.
> > > 
> > > If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> > > don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> > > onto drivers that only want to use this one function.
> > 
> > With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
> > the methods from the stmmac_platform.c module including the bits
> > touched by your patchset. AFAICS semantically both stmmac_platform.c
> > and stmmac_plat_lib.c look the same. They don't do anything on its own
> > but provide some common methods utilized by the glue drivers for some
> > platform-specific setups. So basically stmmac_platform.[ch] is already
> > a library of the common platform methods. There is no need in creating
> > another one.
> 
> I'm not questioning whether it should be merged, I'm questioning whether
> all drivers that I'm touching make use of stmmac_platform.c, so your
> long winded answer was entirely unnecessary. All you needed to do was
> answer the question I asked, rather than teach me how to suck eggs.

So what about the name of the function? Are you happy that it's called
"dwmac_set_tx_clk_gmii" rather than "stmmac_set_tx_clk_gmii" ?

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Serge Semin]

On Wed, Sep 13, 2023 at 03:21:10PM +0100, Russell King (Oracle) wrote:
> On Wed, Sep 13, 2023 at 03:14:47PM +0100, Russell King (Oracle) wrote:
> > On Wed, Sep 13, 2023 at 03:56:07AM +0300, Serge Semin wrote:
> > > On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> > > > On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > > > > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > > > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > > > > 
> > > > > > > Add a platform library of helper functions for common traits in the
> > > > > > > platform drivers. Currently, this is setting the tx clock.
> > > > > > > 
> > > > > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > > ---
> > > > > 
> > > > > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > > > > 
> > > > > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > > > > more helpers on the future that are not only for platform-based drivers?
> > > > > 
> > > > > What is the difference between stmmac_platform.{c,h} and
> > > > > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > > > > may cause confusions like mixed definitions in both of these files.
> > > > > 
> > > > > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > > > > file?
> > > > 
> > > 
> > > > Is stmmac_platform.{c,h} used by all the drivers that are making use of
> > > > this? I'm not entirely sure.
> > > > 
> > > > If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> > > > don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> > > > onto drivers that only want to use this one function.
> > > 
> > > With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
> > > the methods from the stmmac_platform.c module including the bits
> > > touched by your patchset. AFAICS semantically both stmmac_platform.c
> > > and stmmac_plat_lib.c look the same. They don't do anything on its own
> > > but provide some common methods utilized by the glue drivers for some
> > > platform-specific setups. So basically stmmac_platform.[ch] is already
> > > a library of the common platform methods. There is no need in creating
> > > another one.
> > 
> > I'm not questioning whether it should be merged, I'm questioning whether
> > all drivers that I'm touching make use of stmmac_platform.c, so your
> > long winded answer was entirely unnecessary. All you needed to do was
> > answer the question I asked, rather than teach me how to suck eggs.
> 

> So what about the name of the function? Are you happy that it's called
> "dwmac_set_tx_clk_gmii" rather than "stmmac_set_tx_clk_gmii" ?

Not really. I would suggest to preserve the local naming convention:
1. Generic names have stmmac_ prefix.
2. DW *MAC IP-core-specific names have dw(xg|xlg)?mac(100|1000|2|4|5)?_ prefixes.
Alas it was violated in some places (like norm_desc and enh_desc.c
files) but is still mainly preserved in the driver especially in the
stmmac_platform.c which is concerned in this case.

-Serge(y)

> 
> -- 
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

On Thu, Sep 14, 2023 at 01:42:19PM +0300, Serge Semin wrote:
> On Wed, Sep 13, 2023 at 03:21:10PM +0100, Russell King (Oracle) wrote:
> > On Wed, Sep 13, 2023 at 03:14:47PM +0100, Russell King (Oracle) wrote:
> > > On Wed, Sep 13, 2023 at 03:56:07AM +0300, Serge Semin wrote:
> > > > On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> > > > > On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > > > > > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > > > > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > > > > > 
> > > > > > > > Add a platform library of helper functions for common traits in the
> > > > > > > > platform drivers. Currently, this is setting the tx clock.
> > > > > > > > 
> > > > > > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > > > ---
> > > > > > 
> > > > > > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > > > > > 
> > > > > > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > > > > > more helpers on the future that are not only for platform-based drivers?
> > > > > > 
> > > > > > What is the difference between stmmac_platform.{c,h} and
> > > > > > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > > > > > may cause confusions like mixed definitions in both of these files.
> > > > > > 
> > > > > > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > > > > > file?
> > > > > 
> > > > 
> > > > > Is stmmac_platform.{c,h} used by all the drivers that are making use of
> > > > > this? I'm not entirely sure.
> > > > > 
> > > > > If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> > > > > don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> > > > > onto drivers that only want to use this one function.
> > > > 
> > > > With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
> > > > the methods from the stmmac_platform.c module including the bits
> > > > touched by your patchset. AFAICS semantically both stmmac_platform.c
> > > > and stmmac_plat_lib.c look the same. They don't do anything on its own
> > > > but provide some common methods utilized by the glue drivers for some
> > > > platform-specific setups. So basically stmmac_platform.[ch] is already
> > > > a library of the common platform methods. There is no need in creating
> > > > another one.
> > > 
> > > I'm not questioning whether it should be merged, I'm questioning whether
> > > all drivers that I'm touching make use of stmmac_platform.c, so your
> > > long winded answer was entirely unnecessary. All you needed to do was
> > > answer the question I asked, rather than teach me how to suck eggs.
> > 
> 
> > So what about the name of the function? Are you happy that it's called
> > "dwmac_set_tx_clk_gmii" rather than "stmmac_set_tx_clk_gmii" ?
> 
> Not really. I would suggest to preserve the local naming convention:
> 1. Generic names have stmmac_ prefix.
> 2. DW *MAC IP-core-specific names have dw(xg|xlg)?mac(100|1000|2|4|5)?_ prefixes.
> Alas it was violated in some places (like norm_desc and enh_desc.c
> files) but is still mainly preserved in the driver especially in the
> stmmac_platform.c which is concerned in this case.

Thanks... so now I have you down as a single-issue reviewer - you spot
something, you comment on it, and that's as far as you go. You don't
seem to bother continuing the review and raising other points - which
leads to lots of wasted time, and lots of patch set iterations, lots
of email on mailing lists, etc.

Do you think you could review the other patches before I go to the
trouble of spinning a v2 please?

Thanks.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Serge Semin]

On Thu, Sep 14, 2023 at 11:48:10AM +0100, Russell King (Oracle) wrote:
> On Thu, Sep 14, 2023 at 01:42:19PM +0300, Serge Semin wrote:
> > On Wed, Sep 13, 2023 at 03:21:10PM +0100, Russell King (Oracle) wrote:
> > > On Wed, Sep 13, 2023 at 03:14:47PM +0100, Russell King (Oracle) wrote:
> > > > On Wed, Sep 13, 2023 at 03:56:07AM +0300, Serge Semin wrote:
> > > > > On Tue, Sep 12, 2023 at 06:08:23PM +0100, Russell King (Oracle) wrote:
> > > > > > On Tue, Sep 12, 2023 at 12:32:40PM +0300, Serge Semin wrote:
> > > > > > > On Tue, Sep 12, 2023 at 07:59:49AM +0000, Jose Abreu wrote:
> > > > > > > > From: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > > > Date: Mon, Sep 11, 2023 at 16:28:40
> > > > > > > > 
> > > > > > > > > Add a platform library of helper functions for common traits in the
> > > > > > > > > platform drivers. Currently, this is setting the tx clock.
> > > > > > > > > 
> > > > > > > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > > > > > > ---
> > > > > > > 
> > > > > > > > >  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
> > > > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
> > > > > > > > >  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
> > > > > > > > 
> > > > > > > > Wouldn't it be better to just call it "stmmac_lib{.c,.h}" in case we need to add
> > > > > > > > more helpers on the future that are not only for platform-based drivers?
> > > > > > > 
> > > > > > > What is the difference between stmmac_platform.{c,h} and
> > > > > > > stmmac_plat_lib.{c,h} files? It isn't clear really. In perspective it
> > > > > > > may cause confusions like mixed definitions in both of these files.
> > > > > > > 
> > > > > > > Why not to use the stmmac_platform.{c,h} instead of adding one more
> > > > > > > file?
> > > > > > 
> > > > > 
> > > > > > Is stmmac_platform.{c,h} used by all the drivers that are making use of
> > > > > > this? I'm not entirely sure.
> > > > > > 
> > > > > > If it is, then yes, it can go in stmmac_platform.[ch]. If not, then I
> > > > > > don't think we'd want the bloat of forcing all of stmmac_platform.[ch]
> > > > > > onto drivers that only want to use this one function.
> > > > > 
> > > > > With a few exceptions almost all the STMMAC/DW*MAC glue drivers use
> > > > > the methods from the stmmac_platform.c module including the bits
> > > > > touched by your patchset. AFAICS semantically both stmmac_platform.c
> > > > > and stmmac_plat_lib.c look the same. They don't do anything on its own
> > > > > but provide some common methods utilized by the glue drivers for some
> > > > > platform-specific setups. So basically stmmac_platform.[ch] is already
> > > > > a library of the common platform methods. There is no need in creating
> > > > > another one.
> > > > 
> > > > I'm not questioning whether it should be merged, I'm questioning whether
> > > > all drivers that I'm touching make use of stmmac_platform.c, so your
> > > > long winded answer was entirely unnecessary. All you needed to do was
> > > > answer the question I asked, rather than teach me how to suck eggs.
> > > 
> > 
> > > So what about the name of the function? Are you happy that it's called
> > > "dwmac_set_tx_clk_gmii" rather than "stmmac_set_tx_clk_gmii" ?
> > 
> > Not really. I would suggest to preserve the local naming convention:
> > 1. Generic names have stmmac_ prefix.
> > 2. DW *MAC IP-core-specific names have dw(xg|xlg)?mac(100|1000|2|4|5)?_ prefixes.
> > Alas it was violated in some places (like norm_desc and enh_desc.c
> > files) but is still mainly preserved in the driver especially in the
> > stmmac_platform.c which is concerned in this case.
> 

> Thanks... so now I have you down as a single-issue reviewer - you spot
> something, you comment on it, and that's as far as you go. You don't
> seem to bother continuing the review and raising other points - which
> leads to lots of wasted time, and lots of patch set iterations, lots
> of email on mailing lists, etc.
> 
> Do you think you could review the other patches before I go to the
> trouble of spinning a v2 please?

Ok. One more note about this patch:

> --- /dev/null
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
> @@ -0,0 +1,29 @@
> +#include <linux/stmmac.h>
> +#include <linux/clk.h>
> +
> +#include "stmmac_plat_lib.h"
> +
> +int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed)
> +{
> +       unsigned long rate;
> +
> +       switch (speed) {
> +       case SPEED_1000:
> +               rate = 125000000;
> +               break;

> +

It's not described in the kernel coding style, but normally the
switch-case operations are defined with no additional line separating
the cases (I guess it gets to be redundant due to the indentations
visually separating the parts anyway). I would have dropped the empty
lines here too especially seeing the stmmac core driver mainly follow
that implicit convention.

> +       case SPEED_100:
> +               rate = 25000000;
> +               break;

> +

ditto

> +       case SPEED_10:
> +               rate = 2500000;
> +               break;

> +

ditto

-Serge(y)

> +       default:
> +               return -ENOTSUPP;
> +       }
> +
> +       return clk_set_rate(tx_clk, rate);
> +}
> +EXPORT_SYMBOL_GPL(dwmac_set_tx_clk_gmii);

...

> 
> Thanks.
> 
> -- 
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Simon Horman]

On Tue, Sep 12, 2023 at 11:20:55PM +0100, Russell King (Oracle) wrote:
> On Tue, Sep 12, 2023 at 04:52:27PM +0200, Simon Horman wrote:
> > On Mon, Sep 11, 2023 at 04:29:11PM +0100, Russell King (Oracle) wrote:
> > > +	default:
> > > +		return -ENOTSUPP;
> > 
> > Checkpatch seems to think that EOPNOTSUPP would be more appropriate
> > as "ENOTSUPP is not a SUSV4 error code".
> 
> It needs to be an error code that clk_set_rate() below isn't going to
> return - because if clk_set_rate() does return it, then the users are
> going to end up issuing an incorrect error message to the user. I
> suspect clk_set_rate() could quite legitimately return -EOPNOTSUPP
> or -EINVAL.
> 
> Sadly, the CCF implementation of clk_set_rate() doesn't detail what
> errors it could return, but it looks like -EBUSY, -EINVAL, or something
> from pm_runtime_resume_and_get().

Thanks Russell,

Understood.

In that case perhaps ENOTSUPP is not such a bad choice as:
a) it seems rather unlikely CCF would use it; and
b) the scope of usage is well contained - the helper and any direct callers.

No further objections from my side :)

> 
> Interestingly, while looking at this, pm_runtime_resume_and_get() can
> return '1' if e.g. rpm is disabled and the device is active. It looks
> to me like CCF treats that as an error in multiple locations.

The plot thickens...

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

On Tue, Sep 12, 2023 at 04:52:27PM +0200, Simon Horman wrote:
> On Mon, Sep 11, 2023 at 04:29:11PM +0100, Russell King (Oracle) wrote:
> > +	default:
> > +		return -ENOTSUPP;
> 
> Checkpatch seems to think that EOPNOTSUPP would be more appropriate
> as "ENOTSUPP is not a SUSV4 error code".

It needs to be an error code that clk_set_rate() below isn't going to
return - because if clk_set_rate() does return it, then the users are
going to end up issuing an incorrect error message to the user. I
suspect clk_set_rate() could quite legitimately return -EOPNOTSUPP
or -EINVAL.

Sadly, the CCF implementation of clk_set_rate() doesn't detail what
errors it could return, but it looks like -EBUSY, -EINVAL, or something
from pm_runtime_resume_and_get().

Interestingly, while looking at this, pm_runtime_resume_and_get() can
return '1' if e.g. rpm is disabled and the device is active. It looks
to me like CCF treats that as an error in multiple locations.

> > +	}
> > +
> > +	return clk_set_rate(tx_clk, rate);
> > +}
> > +EXPORT_SYMBOL_GPL(dwmac_set_tx_clk_gmii);

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Simon Horman]

On Mon, Sep 11, 2023 at 04:29:11PM +0100, Russell King (Oracle) wrote:
> Add a platform library of helper functions for common traits in the
> platform drivers. Currently, this is setting the tx clock.
> 
> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Hi Russell,

some minor issues raised by checkpatch follow.

> ---
>  drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
>  .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
>  .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
>  3 files changed, 38 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
>  create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
> index 5b57aee19267..ba2cbfa0c9d1 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/Makefile
> +++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
> @@ -6,7 +6,7 @@ stmmac-objs:= stmmac_main.o stmmac_ethtool.o stmmac_mdio.o ring_mode.o	\
>  	      mmc_core.o stmmac_hwtstamp.o stmmac_ptp.o dwmac4_descs.o	\
>  	      dwmac4_dma.o dwmac4_lib.o dwmac4_core.o dwmac5.o hwif.o \
>  	      stmmac_tc.o dwxgmac2_core.o dwxgmac2_dma.o dwxgmac2_descs.o \
> -	      stmmac_xdp.o \
> +	      stmmac_xdp.o stmmac_plat_lib.o \
>  	      $(stmmac-y)
>  
>  stmmac-$(CONFIG_STMMAC_SELFTESTS) += stmmac_selftests.o
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
> new file mode 100644
> index 000000000000..abb9f512bb0e
> --- /dev/null
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
> @@ -0,0 +1,29 @@

Is an SPDX identifier appropriate here?

> +#include <linux/stmmac.h>
> +#include <linux/clk.h>
> +
> +#include "stmmac_plat_lib.h"
> +
> +int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed)
> +{
> +	unsigned long rate;
> +
> +	switch (speed) {
> +	case SPEED_1000:
> +		rate = 125000000;
> +		break;
> +
> +	case SPEED_100:
> +		rate = 25000000;
> +		break;
> +
> +	case SPEED_10:
> +		rate = 2500000;
> +		break;
> +
> +	default:
> +		return -ENOTSUPP;

Checkpatch seems to think that EOPNOTSUPP would be more appropriate
as "ENOTSUPP is not a SUSV4 error code".

> +	}
> +
> +	return clk_set_rate(tx_clk, rate);
> +}
> +EXPORT_SYMBOL_GPL(dwmac_set_tx_clk_gmii);

...

Re: [PATCH net-next 1/6] net: stmmac: add platform library

[Paolo Abeni]

On Mon, 2023-09-11 at 16:29 +0100, Russell King (Oracle) wrote:
> Add a platform library of helper functions for common traits in the
> platform drivers. Currently, this is setting the tx clock.
> 
> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

FTR, two copies of this series landed on the ML. I'm marking the no-
cover-letter version as Superseded, but please have a look at the
comments there, too.

Thanks,

Paolo

[PATCH net-next 1/6] net: stmmac: add platform library

[Russell King (Oracle)]

Add a platform library of helper functions for common traits in the
platform drivers. Currently, this is setting the tx clock.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/Makefile  |  2 +-
 .../ethernet/stmicro/stmmac/stmmac_plat_lib.c | 29 +++++++++++++++++++
 .../ethernet/stmicro/stmmac/stmmac_plat_lib.h |  8 +++++
 3 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
 create mode 100644 drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h

diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
index 5b57aee19267..ba2cbfa0c9d1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Makefile
+++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
@@ -6,7 +6,7 @@ stmmac-objs:= stmmac_main.o stmmac_ethtool.o stmmac_mdio.o ring_mode.o	\
 	      mmc_core.o stmmac_hwtstamp.o stmmac_ptp.o dwmac4_descs.o	\
 	      dwmac4_dma.o dwmac4_lib.o dwmac4_core.o dwmac5.o hwif.o \
 	      stmmac_tc.o dwxgmac2_core.o dwxgmac2_dma.o dwxgmac2_descs.o \
-	      stmmac_xdp.o \
+	      stmmac_xdp.o stmmac_plat_lib.o \
 	      $(stmmac-y)
 
 stmmac-$(CONFIG_STMMAC_SELFTESTS) += stmmac_selftests.o
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
new file mode 100644
index 000000000000..abb9f512bb0e
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.c
@@ -0,0 +1,29 @@
+#include <linux/stmmac.h>
+#include <linux/clk.h>
+
+#include "stmmac_plat_lib.h"
+
+int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed)
+{
+	unsigned long rate;
+
+	switch (speed) {
+	case SPEED_1000:
+		rate = 125000000;
+		break;
+
+	case SPEED_100:
+		rate = 25000000;
+		break;
+
+	case SPEED_10:
+		rate = 2500000;
+		break;
+
+	default:
+		return -ENOTSUPP;
+	}
+
+	return clk_set_rate(tx_clk, rate);
+}
+EXPORT_SYMBOL_GPL(dwmac_set_tx_clk_gmii);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h
new file mode 100644
index 000000000000..926fdce379b3
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_plat_lib.h
@@ -0,0 +1,8 @@
+#ifndef STMMAC_PLAT_LIB_H
+#define STMMAC_PLAT_LIB_H
+
+struct clk;
+
+int dwmac_set_tx_clk_gmii(struct clk *tx_clk, int speed);
+
+#endif
-- 
2.30.2