Re: [PATCH net v11 3/3] net/8390: apne.c - add 100 Mbit support to apne.c driver

Hi Michael,

On Thu, Nov 18, 2021 at 5:58 AM Michael Schmitz [off-list ref] wrote:

On 18/11/21 03:42, Geert Uytterhoeven wrote:

quoted

On Mon, Nov 15, 2021 at 12:40 AM Michael Schmitz [off-list ref] wrote:

quoted

Add module parameter, IO mode autoprobe and PCMCIA reset code
required to support 100 Mbit PCMCIA ethernet cards on Amiga.

10 Mbit and 100 Mbit mode are supported by the same module.
Use the core PCMCIA cftable parser to detect 16 bit cards,
and automatically enable 16 bit ISA IO access for those cards
by changing isa_type at runtime. The user must select PCCARD
and PCMCIA in the kernel config to make the necessary support
modules available

Code to reset the PCMCIA hardware required for 16 bit cards is
also added to the driver probe.

An optional module parameter switches Amiga ISA IO accessors
to 8 or 16 bit access in case autoprobe fails.

Patch modified after patch "[PATCH RFC net-next] Amiga PCMCIA
100 MBit card support" submitted to netdev 2018/09/16 by Alex
Kazik [off-list ref].

CC: netdev@vger.kernel.org
Link: https://lore.kernel.org/r/1622958877-2026-1-git-send-email-schmitzmic@gmail.com (local)
Tested-by: Alex Kazik <redacted>
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>

quoted

quoted

--- a/drivers/net/ethernet/8390/apne.c
+++ b/drivers/net/ethernet/8390/apne.c

@@ -119,6 +119,48 @@ static u32 apne_msg_enable;
 module_param_named(msg_enable, apne_msg_enable, uint, 0444);
 MODULE_PARM_DESC(msg_enable, "Debug message level (see linux/netdevice.h for bitmap)");

+static int apne_100_mbit = -1;
+module_param_named(100_mbit, apne_100_mbit, int, 0444);
+MODULE_PARM_DESC(100_mbit, "Enable 100 Mbit support");
+
+#if IS_ENABLED(CONFIG_PCMCIA)

What if CONFIG_PCMIA=m, and CONFIG_APNE=y?

Fails to build (undefined reference to `pcmcia_parse_tuple').

That's what 'select PCMCIA' was avoiding before, but got vetoed. I can
add a dependency on PCMCIA in the APNE Kconfig entry which does force
APNE the same as what's selected for PCMCIA, but that means we can't
build APNE without PCMCIA anymore. Is there a way to express 'constrain
build type if PCMCIA is enabled, else leave choice to user' ??

#if IS_REACHABLE(CONFIG_PCMIA)

quoted

quoted

@@ -140,6 +182,13 @@ static struct net_device * __init apne_probe(void)

        pr_info("Looking for PCMCIA ethernet card : ");

+       if (apne_100_mbit == 1)
+               isa_type = ISA_TYPE_AG16;
+       else if (apne_100_mbit == 0)
+               isa_type = ISA_TYPE_AG;
+       else
+               pr_cont(" (autoprobing 16 bit mode) ");
+
        /* check if a card is inserted */
        if (!(PCMCIA_INSERTED)) {
                pr_cont("NO PCMCIA card inserted\n");

@@ -167,6 +216,14 @@ static struct net_device * __init apne_probe(void)

        pr_cont("ethernet PCMCIA card inserted\n");

+#if IS_ENABLED(CONFIG_PCMCIA)
+       if (apne_100_mbit < 0 && pcmcia_is_16bit()) {
+               pr_info("16-bit PCMCIA card detected!\n");
+               isa_type = ISA_TYPE_AG16;
+               apne_100_mbit = 1;
+       }

I think you should reset apne_100_mbit to zero if apne_100_mbit < 0
&& !pcmcia_is_16bit(), so rmmod + switching card + modprobe
has a chance to work.

Good catch - though when switching to another card using this same
driver, the module parameter can be used again to select IO mode or
force autoprobe.

The autoprobe won't work if the new card is 8-bit.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds