[PATCH v2 03/16] clk: k210: Remove bypass clock

12 Oct 2020

Now that the PLLs get properly enabled, the bypass clock is no longer
necessary.
Signed-off-by: Sean Anderson seanga2@gmail.com
---
Changes in v2:
- New
drivers/clk/kendryte/Makefile |   2 +-
 drivers/clk/kendryte/bypass.c | 273 ----------------------------------
 drivers/clk/kendryte/clk.c    |  43 ++----
 include/kendryte/bypass.h     |  31 ----
 4 files changed, 15 insertions(+), 334 deletions(-)
 delete mode 100644 drivers/clk/kendryte/bypass.c
 delete mode 100644 include/kendryte/bypass.h

diff --git a/drivers/clk/kendryte/Makefile b/drivers/clk/kendryte/Makefile
index 6fb68253ae..d26bce954f 100644
--- a/drivers/clk/kendryte/Makefile
+++ b/drivers/clk/kendryte/Makefile
@@ -1 +1 @@
-obj-y += bypass.o clk.o pll.o
+obj-y += clk.o pll.o
diff --git a/drivers/clk/kendryte/bypass.c b/drivers/clk/kendryte/bypass.c
deleted file mode 100644
index 5f1986f2cb..0000000000
--- a/drivers/clk/kendryte/bypass.c
+++ /dev/null
@@ -1,273 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Copyright (C) 2020 Sean Anderson seanga2@gmail.com
- */
-
-#define LOG_CATEGORY UCLASS_CLK
-
-#include <common.h>
-#include <clk.h>
-#include <clk-uclass.h>
-#include <dm.h>
-#include <log.h>
-#include <kendryte/bypass.h>
-#include <linux/clk-provider.h>
-#include <linux/err.h>
-
-#define CLK_K210_BYPASS "k210_clk_bypass"
-
-/*
- * This is a small driver to do a software bypass of a clock if hardware bypass
- * is not working. I have tried to write this in a generic fashion, so that it
- * could be potentially broken out of the kendryte code at some future date.
- *
- * Say you have the following clock configuration
- *
- * +---+ +---+
- * |osc| |pll|
- * +---+ +---+
- *         ^
- *        /|
- *       / |
- *      /  |
- *     /   |
- *    /    |
- * +---+ +---+
- * |clk| |clk|
- * +---+ +---+
- *
- * But the pll does not have a bypass, so when you configure the pll, the
- * configuration needs to change to look like
- *
- * +---+ +---+
- * |osc| |pll|
- * +---+ +---+
- *   ^
- *   |\
- *   | \
- *   |  \
- *   |   \
- *   |    \
- * +---+ +---+
- * |clk| |clk|
- * +---+ +---+
- *
- * To set this up, create a bypass clock with bypassee=pll and alt=osc. When
- * creating the child clocks, set their parent to the bypass clock. After
- * creating all the children, call k210_bypass_setchildren().
- */
-
-static int k210_bypass_dobypass(struct k210_bypass *bypass)
-{
-	int ret, i;
-
-	/*
-	 * If we already have saved parents, then the children are already
-	 * bypassed
-	 */
-	if (bypass->child_count && bypass->saved_parents[0])
-		return 0;
-
-	for (i = 0; i < bypass->child_count; i++) {
-		struct clk *child = bypass->children[i];
-		struct clk *parent = clk_get_parent(child);
-
-		if (IS_ERR(parent)) {
-			for (; i; i--)
-				bypass->saved_parents[i] = NULL;
-			return PTR_ERR(parent);
-		}
-		bypass->saved_parents[i] = parent;
-	}
-
-	for (i = 0; i < bypass->child_count; i++) {
-		struct clk *child = bypass->children[i];
-
-		ret = clk_set_parent(child, bypass->alt);
-		if (ret) {
-			for (; i; i--)
-				clk_set_parent(bypass->children[i],
-					       bypass->saved_parents[i]);
-			for (i = 0; i < bypass->child_count; i++)
-				bypass->saved_parents[i] = NULL;
-			return ret;
-		}
-	}
-
-	return 0;
-}
-
-static int k210_bypass_unbypass(struct k210_bypass *bypass)
-{
-	int err, ret, i;
-
-	if (!bypass->child_count && !bypass->saved_parents[0]) {
-		log_warning("Cannot unbypass children; dobypass not called first\n");
-		return 0;
-	}
-
-	ret = 0;
-	for (i = 0; i < bypass->child_count; i++) {
-		err = clk_set_parent(bypass->children[i],
-				     bypass->saved_parents[i]);
-		if (err)
-			ret = err;
-		bypass->saved_parents[i] = NULL;
-	}
-	return ret;
-}
-
-static ulong k210_bypass_get_rate(struct clk *clk)
-{
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-	const struct clk_ops *ops = bypass->bypassee_ops;
-
-	if (ops->get_rate)
-		return ops->get_rate(bypass->bypassee);
-	else
-		return clk_get_parent_rate(bypass->bypassee);
-}
-
-static ulong k210_bypass_set_rate(struct clk *clk, unsigned long rate)
-{
-	int ret;
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-	const struct clk_ops *ops = bypass->bypassee_ops;
-
-	/* Don't bother bypassing if we aren't going to set the rate */
-	if (!ops->set_rate)
-		return k210_bypass_get_rate(clk);
-
-	ret = k210_bypass_dobypass(bypass);
-	if (ret)
-		return ret;
-
-	ret = ops->set_rate(bypass->bypassee, rate);
-	if (ret < 0)
-		return ret;
-
-	return k210_bypass_unbypass(bypass);
-}
-
-static int k210_bypass_set_parent(struct clk *clk, struct clk *parent)
-{
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-	const struct clk_ops *ops = bypass->bypassee_ops;
-
-	if (ops->set_parent)
-		return ops->set_parent(bypass->bypassee, parent);
-	else
-		return -ENOTSUPP;
-}
-
-/*
- * For these next two functions, do the bypassing even if there is no
- * en-/-disable function, since the bypassing itself can be observed in between
- * calls.
- */
-static int k210_bypass_enable(struct clk *clk)
-{
-	int ret;
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-	const struct clk_ops *ops = bypass->bypassee_ops;
-
-	ret = k210_bypass_dobypass(bypass);
-	if (ret)
-		return ret;
-
-	if (ops->enable)
-		ret = ops->enable(bypass->bypassee);
-	else
-		ret = 0;
-	if (ret)
-		return ret;
-
-	return k210_bypass_unbypass(bypass);
-}
-
-static int k210_bypass_disable(struct clk *clk)
-{
-	int ret;
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-	const struct clk_ops *ops = bypass->bypassee_ops;
-
-	ret = k210_bypass_dobypass(bypass);
-	if (ret)
-		return ret;
-
-	if (ops->disable)
-		return ops->disable(bypass->bypassee);
-	else
-		return 0;
-}
-
-static const struct clk_ops k210_bypass_ops = {
-	.get_rate = k210_bypass_get_rate,
-	.set_rate = k210_bypass_set_rate,
-	.set_parent = k210_bypass_set_parent,
-	.enable = k210_bypass_enable,
-	.disable = k210_bypass_disable,
-};
-
-int k210_bypass_set_children(struct clk *clk, struct clk **children,
-			     size_t child_count)
-{
-	struct k210_bypass *bypass = to_k210_bypass(clk);
-
-	kfree(bypass->saved_parents);
-	if (child_count) {
-		bypass->saved_parents =
-			kcalloc(child_count, sizeof(struct clk *), GFP_KERNEL);
-		if (!bypass->saved_parents)
-			return -ENOMEM;
-	}
-	bypass->child_count = child_count;
-	bypass->children = children;
-
-	return 0;
-}
-
-struct clk *k210_register_bypass_struct(const char *name,
-					const char *parent_name,
-					struct k210_bypass *bypass)
-{
-	int ret;
-	struct clk *clk;
-
-	clk = &bypass->clk;
-
-	ret = clk_register(clk, CLK_K210_BYPASS, name, parent_name);
-	if (ret)
-		return ERR_PTR(ret);
-
-	bypass->bypassee->dev = clk->dev;
-	return clk;
-}
-
-struct clk *k210_register_bypass(const char *name, const char *parent_name,
-				 struct clk *bypassee,
-				 const struct clk_ops *bypassee_ops,
-				 struct clk *alt)
-{
-	struct clk *clk;
-	struct k210_bypass *bypass;
-
-	bypass = kzalloc(sizeof(*bypass), GFP_KERNEL);
-	if (!bypass)
-		return ERR_PTR(-ENOMEM);
-
-	bypass->bypassee = bypassee;
-	bypass->bypassee_ops = bypassee_ops;
-	bypass->alt = alt;
-
-	clk = k210_register_bypass_struct(name, parent_name, bypass);
-	if (IS_ERR(clk))
-		kfree(bypass);
-	return clk;
-}
-
-U_BOOT_DRIVER(k210_bypass) = {
-	.name	= CLK_K210_BYPASS,
-	.id	= UCLASS_CLK,
-	.ops	= &k210_bypass_ops,
-};
diff --git a/drivers/clk/kendryte/clk.c b/drivers/clk/kendryte/clk.c
index bb196961af..e657efc572 100644
--- a/drivers/clk/kendryte/clk.c
+++ b/drivers/clk/kendryte/clk.c
@@ -11,7 +11,6 @@
 #include <log.h>
 #include <mapmem.h>
-#include <kendryte/bypass.h>
 #include <kendryte/pll.h>
/* All methods are delegated to CCF clocks */
@@ -347,10 +346,6 @@ static const struct k210_comp_params k210_comps[] = {
 #undef COMP_NOMUX_ID
 #undef COMP_LIST
-static struct clk *k210_bypass_children = {
-	NULL,
-};
-
 /* Helper functions to create sub-clocks */
 static struct clk_mux *k210_create_mux(const struct k210_mux_params *params,
    			       void *base)
@@ -482,7 +477,7 @@ static int k210_clk_probe(struct udevice *dev)
 {
    int ret;
    const char *in0;
-	struct clk *in0_clk, *bypass;
+	struct clk *in0_clk;
    struct clk_mux *mux;
    struct clk_divider *div;
    struct k210_pll *pll;
@@ -516,17 +511,13 @@ static int k210_clk_probe(struct udevice *dev)
    aclk_sels[0] = in0;
    pll2_sels[0] = in0;
-	/*
-	 * All PLLs have a broken bypass, but pll0 has the CPU downstream, so we
-	 * need to manually reparent it whenever we configure pll0
-	 */
-	pll = k210_create_pll(&k210_plls[0], base);
-	if (pll) {
-		bypass = k210_register_bypass("pll0", in0, &pll->clk,
-					      &k210_pll_ops, in0_clk);
-		clk_dm(K210_CLK_PLL0, bypass);
-	} else {
-		return -ENOMEM;
+	{
+		const struct k210_pll_params *params = &k210_plls[0];
+
+		clk_dm(K210_CLK_PLL0,
+		       k210_register_pll("pll0", in0, base + params->off,
+					 base + params->lock_off, params->shift,
+					 params->width));
    }
{
@@ -565,18 +556,12 @@ static int k210_clk_probe(struct udevice *dev)
    	free(mux);
    	free(div);
    } else {
-		struct clk *aclk =
-			clk_register_composite(NULL, "aclk", aclk_sels,
-					       ARRAY_SIZE(aclk_sels),
-					       &mux->clk, &clk_mux_ops,
-					       &div->clk, &clk_divider_ops,
-					       NULL, NULL, 0);
-		clk_dm(K210_CLK_ACLK, aclk);
-		if (!IS_ERR(aclk)) {
-			k210_bypass_children = aclk;
-			k210_bypass_set_children(bypass,
-						 &k210_bypass_children, 1);
-		}
+		clk_dm(K210_CLK_ACLK,
+		       clk_register_composite(NULL, "aclk", aclk_sels,
+					      ARRAY_SIZE(aclk_sels),
+					      &mux->clk, &clk_mux_ops,
+					      &div->clk, &clk_divider_ops,
+					      NULL, NULL, 0));
    }
#define REGISTER_COMP(id, name) \
diff --git a/include/kendryte/bypass.h b/include/kendryte/bypass.h
deleted file mode 100644
index ab85bbcbfc..0000000000
--- a/include/kendryte/bypass.h
+++ /dev/null
@@ -1,31 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0+ */
-/*
- * Copyright (C) 2020 Sean Anderson seanga2@gmail.com
- */
-#ifndef K210_BYPASS_H
-#define K210_BYPASS_H
-
-struct clk;
-
-struct k210_bypass {
-	struct clk clk;
-	struct clk **children; /* Clocks to reparent */
-	struct clk **saved_parents; /* Parents saved over en-/dis-able */
-	struct clk *bypassee; /* Clock to bypass */
-	const struct clk_ops *bypassee_ops; /* Ops of the bypass clock */
-	struct clk *alt; /* Clock to set children to when bypassing */
-	size_t child_count;
-};
-
-#define to_k210_bypass(_clk) container_of(_clk, struct k210_bypass, clk)
-
-int k210_bypass_set_children(struct clk *clk, struct clk **children,
-			     size_t child_count);
-struct clk *k210_register_bypass_struct(const char *name,
-					const char *parent_name,
-					struct k210_bypass *bypass);
-struct clk *k210_register_bypass(const char *name, const char *parent_name,
-				 struct clk *bypassee,
-				 const struct clk_ops *bypassee_ops,
-				 struct clk *alt);
-#endif /* K210_BYPASS_H */
-- 
2.28.0


    