Re: [PATCH v3 2/3] can: rcar_canfd: Add support for RZ/G2L family
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2021-07-26 09:53:22
Also in:
linux-can, linux-devicetree, linux-renesas-soc, lkml
Hi Prabhakar, On Wed, Jul 21, 2021 at 9:50 PM Lad Prabhakar [off-list ref] wrote:
CANFD block on RZ/G2L SoC is almost identical to one found on R-Car Gen3 SoC's. On RZ/G2L SoC interrupt sources for each channel are split into different sources and the IP doesn't divide (1/2) CANFD clock within the IP. This patch adds compatible string for RZ/G2L family and registers the irq handlers required for CANFD operation. IRQ numbers are now fetched based on names instead of indices. For backward compatibility on non RZ/G2L SoC's we fallback reading based on indices. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Thanks for the update! I think you misunderstood my comment on v1 about the interrupt handlers, cfr. below.
quoted hunk ↗ jump to hunk
--- a/drivers/net/can/rcar/rcar_canfd.c +++ b/drivers/net/can/rcar/rcar_canfd.c
quoted hunk ↗ jump to hunk
@@ -1577,6 +1586,53 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch, priv->can.clock.freq = fcan_freq; dev_info(&pdev->dev, "can_clk rate is %u\n", priv->can.clock.freq); + if (gpriv->chip_id == RENESAS_RZG2L) { + char *irq_name; + int err_irq; + int tx_irq; + + err_irq = platform_get_irq_byname(pdev, ch == 0 ? "ch0_err" : "ch1_err"); + if (err_irq < 0) { + err = err_irq; + goto fail; + } + + tx_irq = platform_get_irq_byname(pdev, ch == 0 ? "ch0_trx" : "ch1_trx"); + if (tx_irq < 0) { + err = tx_irq; + goto fail; + } + + irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, + "canfd.ch%d_err", ch); + if (!irq_name) { + err = -ENOMEM; + goto fail; + } + err = devm_request_irq(&pdev->dev, err_irq, + rcar_canfd_channel_interrupt, 0,
This is the same interrupt handler...
+ irq_name, gpriv);
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq CH Err(%d) failed, error %d\n",
+ err_irq, err);
+ goto fail;
+ }
+ irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+ "canfd.ch%d_trx", ch);
+ if (!irq_name) {
+ err = -ENOMEM;
+ goto fail;
+ }
+ err = devm_request_irq(&pdev->dev, tx_irq,
+ rcar_canfd_channel_interrupt, 0,... as this one.
+ irq_name, gpriv);
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq Tx (%d) failed, error %d\n",
+ tx_irq, err);
+ goto fail;
+ }
+ }
+
if (gpriv->fdmode) {
priv->can.bittiming_const = &rcar_canfd_nom_bittiming_const;
priv->can.data_bittiming_const =quoted hunk ↗ jump to hunk
@@ -1711,20 +1798,51 @@ static int rcar_canfd_probe(struct platform_device *pdev) gpriv->base = addr; /* Request IRQ that's common for both channels */ - err = devm_request_irq(&pdev->dev, ch_irq, - rcar_canfd_channel_interrupt, 0, - "canfd.chn", gpriv); - if (err) { - dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n", - ch_irq, err); - goto fail_dev; + if (gpriv->chip_id == RENESAS_RCAR_GEN3) { + err = devm_request_irq(&pdev->dev, ch_irq, + rcar_canfd_channel_interrupt, 0, + "canfd.ch_int", gpriv); + if (err) { + dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n", + ch_irq, err); + goto fail_dev; + } + + err = devm_request_irq(&pdev->dev, g_irq, + rcar_canfd_global_interrupt, 0, + "canfd.g_int", gpriv); + if (err) { + dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n", + g_irq, err); + goto fail_dev; + } + } else { + err = devm_request_irq(&pdev->dev, g_recc_irq, + rcar_canfd_global_interrupt, 0,
This is the same interrupt handler...
+ "canfd.g_recc", gpriv);
+
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n",
+ g_recc_irq, err);
+ goto fail_dev;
+ }
+
+ err = devm_request_irq(&pdev->dev, g_err_irq,
+ rcar_canfd_global_interrupt, 0,... as this one.
+ "canfd.g_err", gpriv);
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n",
+ g_err_irq, err);
+ goto fail_dev;
+ }
}
- err = devm_request_irq(&pdev->dev, g_irq,
- rcar_canfd_global_interrupt, 0,
- "canfd.gbl", gpriv);
+
+ err = reset_control_reset(gpriv->rstc1);
+ if (err)
+ goto fail_dev;
+ err = reset_control_reset(gpriv->rstc2);
if (err) {
- dev_err(&pdev->dev, "devm_request_irq(%d) failed, error %d\n",
- g_irq, err);
+ reset_control_assert(gpriv->rstc1);
goto fail_dev;
}
I did not object to having fine-grained interrupt handlers on RZ/G2L.
I did object to duplicating code in global and fine-grained interrupt
handlers.
The trick to have both is to let the global interrupt handlers call
(conditionally) into the fine-grained handlers. In pseudo-code:
global_interrupt_handler()
{
if (...)
fine_grained_handler1();
if (...)
fine_grained_handler2();
...
}
On R-Car Gen3, you register the global interrupt handlers, as before.
On RZ/G2L, you register the fine-grained interrupt handlers instead.
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