LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Sam Protsenko <semen.protsenko@linaro.org>
To: Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Chanwoo Choi <cw00.choi@samsung.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Tomasz Figa <tomasz.figa@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>, Stephen Boyd <sboyd@kernel.org>,
	Michael Turquette <mturquette@baylibre.com>,
	Jiri Slaby <jirislaby@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Charles Keepax <ckeepax@opensource.wolfsonmicro.com>,
	Ryu Euiyoul <ryu.real@samsung.com>,
	Tom Gall <tom.gall@linaro.org>,
	Sumit Semwal <sumit.semwal@linaro.org>,
	John Stultz <john.stultz@linaro.org>,
	Amit Pundir <amit.pundir@linaro.org>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org,
	linux-serial@vger.kernel.org
Subject: [PATCH 10/12] clk: samsung: Add Exynos850 clock driver stub
Date: Fri, 30 Jul 2021 17:49:20 +0300	[thread overview]
Message-ID: <20210730144922.29111-11-semen.protsenko@linaro.org> (raw)
In-Reply-To: <20210730144922.29111-1-semen.protsenko@linaro.org>

For now it's just a stub driver to make serial driver work. Later it
will be implemented properly.

This driver doesn't really change clocks, only registers the UART clock
as a fixed-rate clock. Without this clock driver the UART driver won't
work, as it's trying to obtain "uart" clock and fails if it's not able
to. From drivers/tty/serial/samsung_tty.c:

8<------------------------------------------------------------------->8
    ourport->clk = clk_get(&platdev->dev, "uart");
    if (IS_ERR(ourport->clk)) {
        pr_err("%s: Controller clock not found\n",
                dev_name(&platdev->dev));
        ret = PTR_ERR(ourport->clk);
        goto err;
    }
8<------------------------------------------------------------------->8

In order to get functional serial console we have to implement that
minimal clock driver with "uart" clock. It's not necessary to actually
configure clocks, as those are already configured in bootloader, so
kernel can rely on that for now.

80 column limit is broken here to make checkpatch happy, otherwise it
swears about incorrect __initconst usage.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
---
 drivers/clk/samsung/Makefile        |  1 +
 drivers/clk/samsung/clk-exynos850.c | 63 +++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 drivers/clk/samsung/clk-exynos850.c

diff --git a/drivers/clk/samsung/Makefile b/drivers/clk/samsung/Makefile
index 028b2e27a37e..c46cf11e4d0b 100644
--- a/drivers/clk/samsung/Makefile
+++ b/drivers/clk/samsung/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-exynos5433.o
 obj-$(CONFIG_EXYNOS_AUDSS_CLK_CON) += clk-exynos-audss.o
 obj-$(CONFIG_EXYNOS_CLKOUT)	+= clk-exynos-clkout.o
 obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-exynos7.o
+obj-$(CONFIG_EXYNOS_ARM64_COMMON_CLK)	+= clk-exynos850.o
 obj-$(CONFIG_S3C2410_COMMON_CLK)+= clk-s3c2410.o
 obj-$(CONFIG_S3C2410_COMMON_DCLK)+= clk-s3c2410-dclk.o
 obj-$(CONFIG_S3C2412_COMMON_CLK)+= clk-s3c2412.o
diff --git a/drivers/clk/samsung/clk-exynos850.c b/drivers/clk/samsung/clk-exynos850.c
new file mode 100644
index 000000000000..3192ec9bb90b
--- /dev/null
+++ b/drivers/clk/samsung/clk-exynos850.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Samsung Electronics Co., Ltd.
+ * Copyright (C) 2021 Linaro Ltd.
+ *
+ * Common Clock Framework support for Exynos850 SoC.
+ */
+
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <dt-bindings/clock/exynos850.h>
+
+#include "clk.h"
+
+/* Fixed rate clocks generated outside the SoC */
+static struct samsung_fixed_rate_clock exynos850_fixed_rate_ext_clks[] __initdata = {
+	FRATE(OSCCLK, "fin_pll", NULL, 0, 26000000),
+};
+
+/*
+ * Model the UART clock as a fixed-rate clock for now, to make serial driver
+ * work. This clock is already configured in the bootloader.
+ */
+static const struct samsung_fixed_rate_clock exynos850_peri_clks[] __initconst = {
+	FRATE(DOUT_UART, "DOUT_UART", NULL, 0, 200000000),
+};
+
+static const struct of_device_id ext_clk_match[] __initconst = {
+	{ .compatible = "samsung,exynos850-oscclk", .data = (void *)0 },
+	{},
+};
+
+void __init exynos850_clk_init(struct device_node *np)
+{
+	void __iomem *reg_base;
+	struct samsung_clk_provider *ctx;
+
+	if (!np)
+		panic("%s: unable to determine soc\n", __func__);
+
+	reg_base = of_iomap(np, 0);
+	if (!reg_base)
+		panic("%s: failed to map registers\n", __func__);
+
+	ctx = samsung_clk_init(np, reg_base, CLK_NR_CLKS);
+	if (!ctx)
+		panic("%s: unable to allocate ctx\n", __func__);
+
+	samsung_clk_of_register_fixed_ext(ctx,
+			exynos850_fixed_rate_ext_clks,
+			ARRAY_SIZE(exynos850_fixed_rate_ext_clks),
+			ext_clk_match);
+
+	samsung_clk_register_fixed_rate(ctx, exynos850_peri_clks,
+			ARRAY_SIZE(exynos850_peri_clks));
+
+	samsung_clk_of_add_provider(np, ctx);
+}
+
+CLK_OF_DECLARE(exynos850_clk, "samsung,exynos850-clock", exynos850_clk_init);
-- 
2.30.2


  parent reply	other threads:[~2021-07-30 14:50 UTC|newest]

Thread overview: 66+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-30 14:49 [PATCH 00/12] Add minimal support for Exynos850 SoC Sam Protsenko
2021-07-30 14:49 ` [PATCH 01/12] pinctrl: samsung: Fix pinctrl bank pin count Sam Protsenko
2021-07-30 14:49 ` [PATCH 02/12] pinctrl: samsung: Add Exynos850 SoC specific data Sam Protsenko
2021-07-30 15:22   ` Krzysztof Kozlowski
2021-08-02 19:24     ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 03/12] dt-bindings: pinctrl: samsung: Add Exynos850 doc Sam Protsenko
2021-07-30 15:24   ` Krzysztof Kozlowski
2021-07-30 19:31     ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 04/12] tty: serial: samsung: Init USI to keep clocks running Sam Protsenko
2021-07-30 16:31   ` Krzysztof Kozlowski
2021-08-02 23:06     ` Sam Protsenko
2021-08-03  7:37       ` Krzysztof Kozlowski
2021-08-03 11:41         ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 05/12] tty: serial: samsung: Fix driver data macros style Sam Protsenko
2021-07-30 16:34   ` Krzysztof Kozlowski
2021-07-30 14:49 ` [PATCH 06/12] tty: serial: samsung: Add Exynos850 SoC data Sam Protsenko
2021-07-30 15:05   ` Andy Shevchenko
2021-07-30 16:05   ` Krzysztof Kozlowski
2021-07-30 23:10     ` Sam Protsenko
2021-07-31  7:12       ` Krzysztof Kozlowski
2021-07-30 14:49 ` [PATCH 07/12] dt-bindings: serial: samsung: Add Exynos850 doc Sam Protsenko
2021-07-30 16:35   ` Krzysztof Kozlowski
2021-07-30 19:04     ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 08/12] MAINTAINERS: Cover Samsung clock YAML bindings Sam Protsenko
2021-07-30 15:06   ` Andy Shevchenko
2021-07-30 15:25     ` Krzysztof Kozlowski
2021-07-30 17:32       ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 09/12] dt-bindings: clock: Add bindings for Exynos850 clock controller Sam Protsenko
2021-07-30 15:43   ` Krzysztof Kozlowski
2021-08-03 11:55     ` Sam Protsenko
2021-07-30 22:28   ` Rob Herring
2021-07-30 14:49 ` Sam Protsenko [this message]
2021-07-30 15:11   ` [PATCH 10/12] clk: samsung: Add Exynos850 clock driver stub Andy Shevchenko
2021-07-30 17:24     ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 11/12] dt-bindings: interrupt-controller: Add IRQ constants for Exynos850 Sam Protsenko
2021-07-31  8:45   ` Krzysztof Kozlowski
2021-08-03 12:58     ` Sam Protsenko
2021-07-30 14:49 ` [PATCH 12/12] arm64: dts: exynos: Add Exynos850 SoC support Sam Protsenko
2021-07-30 16:50   ` Marc Zyngier
2021-08-04 14:39     ` Sam Protsenko
2021-08-04 15:01       ` Marc Zyngier
2021-08-04 18:37         ` Sam Protsenko
2021-08-05  7:39           ` Marc Zyngier
2021-08-05 15:30             ` Sam Protsenko
2021-08-05 15:50               ` Marc Zyngier
2021-08-04 18:36       ` Krzysztof Kozlowski
2021-08-04 21:30         ` Sam Protsenko
2021-08-05  7:17           ` Krzysztof Kozlowski
2021-08-05  7:30             ` Marc Zyngier
2021-08-05  7:35               ` Krzysztof Kozlowski
2021-07-31  9:03   ` Krzysztof Kozlowski
2021-08-05 23:06     ` Sam Protsenko
2021-08-06  7:48       ` Krzysztof Kozlowski
2021-08-06 12:07         ` Sam Protsenko
2021-08-06 12:32           ` Krzysztof Kozlowski
2021-08-06 12:48             ` Krzysztof Kozlowski
2021-08-06 16:57               ` Sam Protsenko
2021-08-06 20:32             ` Paweł Chmiel
2021-09-06 15:16               ` Sam Protsenko
2021-07-30 15:18 ` [PATCH 00/12] Add minimal support for Exynos850 SoC Krzysztof Kozlowski
2021-07-30 17:21   ` Krzysztof Kozlowski
2021-07-30 19:02     ` Sam Protsenko
2021-07-31  7:29       ` Krzysztof Kozlowski
2021-07-31  8:12         ` Krzysztof Kozlowski
2021-08-02 23:27           ` Sam Protsenko
2021-08-03  7:41             ` Krzysztof Kozlowski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210730144922.29111-11-semen.protsenko@linaro.org \
    --to=semen.protsenko@linaro.org \
    --cc=amit.pundir@linaro.org \
    --cc=ckeepax@opensource.wolfsonmicro.com \
    --cc=cw00.choi@samsung.com \
    --cc=devicetree@vger.kernel.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=jirislaby@kernel.org \
    --cc=john.stultz@linaro.org \
    --cc=krzysztof.kozlowski@canonical.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-gpio@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --cc=mturquette@baylibre.com \
    --cc=robh+dt@kernel.org \
    --cc=ryu.real@samsung.com \
    --cc=s.nawrocki@samsung.com \
    --cc=sboyd@kernel.org \
    --cc=sumit.semwal@linaro.org \
    --cc=tom.gall@linaro.org \
    --cc=tomasz.figa@gmail.com \
    --subject='Re: [PATCH 10/12] clk: samsung: Add Exynos850 clock driver stub' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).