[PATCH v4 1/4] clk: mxl: Switch from direct readl/writel based IO to regmap based IO
From: Rahul Tanwar
Date: Thu Oct 13 2022 - 02:49:07 EST
Earlier version of driver used direct io remapped register read
writes using readl/writel. But we need secure boot access which
is only possible when registers are read & written using regmap.
This is because the security bus/hook is written & coupled only
with regmap layer.
Switch the driver from direct readl/writel based register accesses
to regmap based register accesses.
Additionally, update the license headers to latest status.
Reviewed-by: Yi xin Zhu <yzhu@xxxxxxxxxxxxx>
Signed-off-by: Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
---
drivers/clk/x86/Kconfig | 5 +++--
drivers/clk/x86/clk-cgu-pll.c | 10 +++++----
drivers/clk/x86/clk-cgu.c | 5 +++--
drivers/clk/x86/clk-cgu.h | 38 +++++++++++++++++++----------------
drivers/clk/x86/clk-lgm.c | 13 ++++++++----
5 files changed, 42 insertions(+), 29 deletions(-)
diff --git a/drivers/clk/x86/Kconfig b/drivers/clk/x86/Kconfig
index 69642e15fcc1..ced99e082e3d 100644
--- a/drivers/clk/x86/Kconfig
+++ b/drivers/clk/x86/Kconfig
@@ -1,8 +1,9 @@
# SPDX-License-Identifier: GPL-2.0-only
config CLK_LGM_CGU
depends on OF && HAS_IOMEM && (X86 || COMPILE_TEST)
+ select MFD_SYSCON
select OF_EARLY_FLATTREE
bool "Clock driver for Lightning Mountain(LGM) platform"
help
- Clock Generation Unit(CGU) driver for Intel Lightning Mountain(LGM)
- network processor SoC.
+ Clock Generation Unit(CGU) driver for MaxLinear's x86 based
+ Lightning Mountain(LGM) network processor SoC.
diff --git a/drivers/clk/x86/clk-cgu-pll.c b/drivers/clk/x86/clk-cgu-pll.c
index 3179557b5f78..c83083affe88 100644
--- a/drivers/clk/x86/clk-cgu-pll.c
+++ b/drivers/clk/x86/clk-cgu-pll.c
@@ -1,8 +1,9 @@
// SPDX-License-Identifier: GPL-2.0
/*
+ * Copyright (C) 2020-2022 MaxLinear, Inc.
* Copyright (C) 2020 Intel Corporation.
- * Zhu YiXin <yixin.zhu@xxxxxxxxx>
- * Rahul Tanwar <rahul.tanwar@xxxxxxxxx>
+ * Zhu Yixin <yzhu@xxxxxxxxxxxxx>
+ * Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
*/
#include <linux/clk-provider.h>
@@ -76,8 +77,9 @@ static int lgm_pll_enable(struct clk_hw *hw)
spin_lock_irqsave(&pll->lock, flags);
lgm_set_clk_val(pll->membase, pll->reg, 0, 1, 1);
- ret = readl_poll_timeout_atomic(pll->membase + pll->reg,
- val, (val & 0x1), 1, 100);
+ ret = regmap_read_poll_timeout_atomic(pll->membase, pll->reg,
+ val, (val & 0x1), 1, 100);
+
spin_unlock_irqrestore(&pll->lock, flags);
return ret;
diff --git a/drivers/clk/x86/clk-cgu.c b/drivers/clk/x86/clk-cgu.c
index 33de600e0c38..f5f30a18f486 100644
--- a/drivers/clk/x86/clk-cgu.c
+++ b/drivers/clk/x86/clk-cgu.c
@@ -1,8 +1,9 @@
// SPDX-License-Identifier: GPL-2.0
/*
+ * Copyright (C) 2020-2022 MaxLinear, Inc.
* Copyright (C) 2020 Intel Corporation.
- * Zhu YiXin <yixin.zhu@xxxxxxxxx>
- * Rahul Tanwar <rahul.tanwar@xxxxxxxxx>
+ * Zhu Yixin <yzhu@xxxxxxxxxxxxx>
+ * Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
*/
#include <linux/clk-provider.h>
#include <linux/device.h>
diff --git a/drivers/clk/x86/clk-cgu.h b/drivers/clk/x86/clk-cgu.h
index 4e22bfb22312..dbcb66468797 100644
--- a/drivers/clk/x86/clk-cgu.h
+++ b/drivers/clk/x86/clk-cgu.h
@@ -1,18 +1,19 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
- * Copyright(c) 2020 Intel Corporation.
- * Zhu YiXin <yixin.zhu@xxxxxxxxx>
- * Rahul Tanwar <rahul.tanwar@xxxxxxxxx>
+ * Copyright (C) 2020-2022 MaxLinear, Inc.
+ * Copyright (C) 2020 Intel Corporation.
+ * Zhu Yixin <yzhu@xxxxxxxxxxxxx>
+ * Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
*/
#ifndef __CLK_CGU_H
#define __CLK_CGU_H
-#include <linux/io.h>
+#include <linux/regmap.h>
struct lgm_clk_mux {
struct clk_hw hw;
- void __iomem *membase;
+ struct regmap *membase;
unsigned int reg;
u8 shift;
u8 width;
@@ -22,7 +23,7 @@ struct lgm_clk_mux {
struct lgm_clk_divider {
struct clk_hw hw;
- void __iomem *membase;
+ struct regmap *membase;
unsigned int reg;
u8 shift;
u8 width;
@@ -35,7 +36,7 @@ struct lgm_clk_divider {
struct lgm_clk_ddiv {
struct clk_hw hw;
- void __iomem *membase;
+ struct regmap *membase;
unsigned int reg;
u8 shift0;
u8 width0;
@@ -53,7 +54,7 @@ struct lgm_clk_ddiv {
struct lgm_clk_gate {
struct clk_hw hw;
- void __iomem *membase;
+ struct regmap *membase;
unsigned int reg;
u8 shift;
unsigned long flags;
@@ -77,7 +78,7 @@ enum lgm_clk_type {
* @clk_data: array of hw clocks and clk number.
*/
struct lgm_clk_provider {
- void __iomem *membase;
+ struct regmap *membase;
struct device_node *np;
struct device *dev;
struct clk_hw_onecell_data clk_data;
@@ -92,7 +93,7 @@ enum pll_type {
struct lgm_clk_pll {
struct clk_hw hw;
- void __iomem *membase;
+ struct regmap *membase;
unsigned int reg;
unsigned long flags;
enum pll_type type;
@@ -300,29 +301,32 @@ struct lgm_clk_branch {
.div = _d, \
}
-static inline void lgm_set_clk_val(void __iomem *membase, u32 reg,
+static inline void lgm_set_clk_val(struct regmap *membase, u32 reg,
u8 shift, u8 width, u32 set_val)
{
u32 mask = (GENMASK(width - 1, 0) << shift);
- u32 regval;
- regval = readl(membase + reg);
- regval = (regval & ~mask) | ((set_val << shift) & mask);
- writel(regval, membase + reg);
+ regmap_update_bits(membase, reg, mask, set_val << shift);
}
-static inline u32 lgm_get_clk_val(void __iomem *membase, u32 reg,
+static inline u32 lgm_get_clk_val(struct regmap *membase, u32 reg,
u8 shift, u8 width)
{
u32 mask = (GENMASK(width - 1, 0) << shift);
u32 val;
- val = readl(membase + reg);
+ if (regmap_read(membase, reg, &val)) {
+ WARN_ONCE(1, "Failed to read clk reg: 0x%x\n", reg);
+ return 0;
+ }
+
val = (val & mask) >> shift;
return val;
}
+
+
int lgm_clk_register_branches(struct lgm_clk_provider *ctx,
const struct lgm_clk_branch *list,
unsigned int nr_clk);
diff --git a/drivers/clk/x86/clk-lgm.c b/drivers/clk/x86/clk-lgm.c
index 020f4e83a5cc..4fa2bcaf71c8 100644
--- a/drivers/clk/x86/clk-lgm.c
+++ b/drivers/clk/x86/clk-lgm.c
@@ -1,10 +1,12 @@
// SPDX-License-Identifier: GPL-2.0
/*
+ * Copyright (C) 2020-2022 MaxLinear, Inc.
* Copyright (C) 2020 Intel Corporation.
- * Zhu YiXin <yixin.zhu@xxxxxxxxx>
- * Rahul Tanwar <rahul.tanwar@xxxxxxxxx>
+ * Zhu Yixin <yzhu@xxxxxxxxxxxxx>
+ * Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
*/
#include <linux/clk-provider.h>
+#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <dt-bindings/clock/intel,lgm-clk.h>
@@ -433,9 +435,12 @@ static int lgm_cgu_probe(struct platform_device *pdev)
ctx->clk_data.num = CLK_NR_CLKS;
- ctx->membase = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(ctx->membase))
+ ctx->membase = syscon_node_to_regmap(np);
+ if (IS_ERR_OR_NULL(ctx->membase)) {
+ dev_err(dev, "Failed to get clk CGU iomem\n");
return PTR_ERR(ctx->membase);
+ }
+
ctx->np = np;
ctx->dev = dev;
--
2.17.1