drivers/clk/ingenic/jz4755-cgu.c
Source file repositories/reference/linux-study-clean/drivers/clk/ingenic/jz4755-cgu.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/clk/ingenic/jz4755-cgu.c- Extension
.c- Size
- 7497 bytes
- Lines
- 347
- Domain
- Driver Families
- Bucket
- drivers/clk
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/clk-provider.hlinux/delay.hlinux/of.hdt-bindings/clock/ingenic,jz4755-cgu.hcgu.hpm.h
Detected Declarations
function jz4755_cgu_init
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/*
* Ingenic JZ4755 SoC CGU driver
* Heavily based on JZ4725b CGU driver
*
* Copyright (C) 2022 Siarhei Volkau
* Author: Siarhei Volkau <lis8215@gmail.com>
*/
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <dt-bindings/clock/ingenic,jz4755-cgu.h>
#include "cgu.h"
#include "pm.h"
/* CGU register offsets */
#define CGU_REG_CPCCR 0x00
#define CGU_REG_CPPCR 0x10
#define CGU_REG_CLKGR 0x20
#define CGU_REG_OPCR 0x24
#define CGU_REG_I2SCDR 0x60
#define CGU_REG_LPCDR 0x64
#define CGU_REG_MSCCDR 0x68
#define CGU_REG_SSICDR 0x74
#define CGU_REG_CIMCDR 0x7C
static struct ingenic_cgu *cgu;
static const s8 pll_od_encoding[4] = {
0x0, 0x1, -1, 0x3,
};
static const u8 jz4755_cgu_cpccr_div_table[] = {
1, 2, 3, 4, 6, 8,
};
static const u8 jz4755_cgu_pll_half_div_table[] = {
2, 1,
};
static const struct ingenic_cgu_clk_info jz4755_cgu_clocks[] = {
/* External clocks */
[JZ4755_CLK_EXT] = { "ext", CGU_CLK_EXT },
[JZ4755_CLK_OSC32K] = { "osc32k", CGU_CLK_EXT },
[JZ4755_CLK_PLL] = {
"pll", CGU_CLK_PLL,
.parents = { JZ4755_CLK_EXT, },
.pll = {
.reg = CGU_REG_CPPCR,
.rate_multiplier = 1,
.m_shift = 23,
.m_bits = 9,
.m_offset = 2,
.n_shift = 18,
.n_bits = 5,
.n_offset = 2,
.od_shift = 16,
.od_bits = 2,
.od_max = 4,
.od_encoding = pll_od_encoding,
.stable_bit = 10,
.bypass_reg = CGU_REG_CPPCR,
.bypass_bit = 9,
.enable_bit = 8,
},
},
/* Muxes & dividers */
[JZ4755_CLK_PLL_HALF] = {
"pll half", CGU_CLK_DIV,
.parents = { JZ4755_CLK_PLL, },
.div = {
CGU_REG_CPCCR, 21, 1, 1, -1, -1, -1, 0,
jz4755_cgu_pll_half_div_table,
},
},
[JZ4755_CLK_EXT_HALF] = {
"ext half", CGU_CLK_DIV,
.parents = { JZ4755_CLK_EXT, },
.div = {
CGU_REG_CPCCR, 30, 1, 1, -1, -1, -1, 0,
NULL,
Annotation
- Immediate include surface: `linux/clk-provider.h`, `linux/delay.h`, `linux/of.h`, `dt-bindings/clock/ingenic,jz4755-cgu.h`, `cgu.h`, `pm.h`.
- Detected declarations: `function jz4755_cgu_init`.
- Atlas domain: Driver Families / drivers/clk.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.