drivers/clk/imx/clk-imx27.c
Source file repositories/reference/linux-study-clean/drivers/clk/imx/clk-imx27.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/clk/imx/clk-imx27.c- Extension
.c- Size
- 10673 bytes
- Lines
- 193
- 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.hlinux/clk-provider.hlinux/clkdev.hlinux/err.hlinux/io.hlinux/of.hlinux/of_address.hdt-bindings/clock/imx27-clock.hsoc/imx/revision.hasm/irq.hclk.h
Detected Declarations
function _mx27_clocks_initfunction mx27_clocks_init_dtfunction for_each_compatible_node_scoped
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <dt-bindings/clock/imx27-clock.h>
#include <soc/imx/revision.h>
#include <asm/irq.h>
#include "clk.h"
#define MX27_CCM_BASE_ADDR 0x10027000
#define MX27_GPT1_BASE_ADDR 0x10003000
#define MX27_INT_GPT1 (NR_IRQS_LEGACY + 26)
static void __iomem *ccm __initdata;
/* Register offsets */
#define CCM_CSCR (ccm + 0x00)
#define CCM_MPCTL0 (ccm + 0x04)
#define CCM_MPCTL1 (ccm + 0x08)
#define CCM_SPCTL0 (ccm + 0x0c)
#define CCM_SPCTL1 (ccm + 0x10)
#define CCM_PCDR0 (ccm + 0x18)
#define CCM_PCDR1 (ccm + 0x1c)
#define CCM_PCCR0 (ccm + 0x20)
#define CCM_PCCR1 (ccm + 0x24)
#define CCM_CCSR (ccm + 0x28)
static const char *vpu_sel_clks[] = { "spll", "mpll_main2", };
static const char *cpu_sel_clks[] = { "mpll_main2", "mpll", };
static const char *mpll_sel_clks[] = { "fpm", "mpll_osc_sel", };
static const char *mpll_osc_sel_clks[] = { "ckih_gate", "ckih_div1p5", };
static const char *clko_sel_clks[] = {
"ckil", "fpm", "ckih_gate", "ckih_gate",
"ckih_gate", "mpll", "spll", "cpu_div",
"ahb", "ipg", "per1_div", "per2_div",
"per3_div", "per4_div", "ssi1_div", "ssi2_div",
"nfc_div", "mshc_div", "vpu_div", "60m",
"32k", "usb_div", "dptc",
};
static const char *ssi_sel_clks[] = { "spll_gate", "mpll", };
static struct clk *clk[IMX27_CLK_MAX];
static struct clk_onecell_data clk_data;
static void __init _mx27_clocks_init(unsigned long fref)
{
BUG_ON(!ccm);
clk[IMX27_CLK_DUMMY] = imx_clk_fixed("dummy", 0);
clk[IMX27_CLK_CKIH] = imx_clk_fixed("ckih", fref);
clk[IMX27_CLK_CKIL] = imx_clk_fixed("ckil", 32768);
clk[IMX27_CLK_FPM] = imx_clk_fixed_factor("fpm", "ckil", 1024, 1);
clk[IMX27_CLK_CKIH_DIV1P5] = imx_clk_fixed_factor("ckih_div1p5", "ckih_gate", 2, 3);
clk[IMX27_CLK_CKIH_GATE] = imx_clk_gate_dis("ckih_gate", "ckih", CCM_CSCR, 3);
clk[IMX27_CLK_MPLL_OSC_SEL] = imx_clk_mux("mpll_osc_sel", CCM_CSCR, 4, 1, mpll_osc_sel_clks, ARRAY_SIZE(mpll_osc_sel_clks));
clk[IMX27_CLK_MPLL_SEL] = imx_clk_mux("mpll_sel", CCM_CSCR, 16, 1, mpll_sel_clks, ARRAY_SIZE(mpll_sel_clks));
clk[IMX27_CLK_MPLL] = imx_clk_pllv1(IMX_PLLV1_IMX27, "mpll", "mpll_sel", CCM_MPCTL0);
clk[IMX27_CLK_SPLL] = imx_clk_pllv1(IMX_PLLV1_IMX27, "spll", "ckih_gate", CCM_SPCTL0);
clk[IMX27_CLK_SPLL_GATE] = imx_clk_gate("spll_gate", "spll", CCM_CSCR, 1);
clk[IMX27_CLK_MPLL_MAIN2] = imx_clk_fixed_factor("mpll_main2", "mpll", 2, 3);
if (mx27_revision() >= IMX_CHIP_REVISION_2_0) {
clk[IMX27_CLK_AHB] = imx_clk_divider("ahb", "mpll_main2", CCM_CSCR, 8, 2);
clk[IMX27_CLK_IPG] = imx_clk_fixed_factor("ipg", "ahb", 1, 2);
} else {
clk[IMX27_CLK_AHB] = imx_clk_divider("ahb", "mpll_main2", CCM_CSCR, 9, 4);
clk[IMX27_CLK_IPG] = imx_clk_divider("ipg", "ahb", CCM_CSCR, 8, 1);
}
clk[IMX27_CLK_MSHC_DIV] = imx_clk_divider("mshc_div", "ahb", CCM_PCDR0, 0, 6);
clk[IMX27_CLK_NFC_DIV] = imx_clk_divider("nfc_div", "ahb", CCM_PCDR0, 6, 4);
clk[IMX27_CLK_PER1_DIV] = imx_clk_divider("per1_div", "mpll_main2", CCM_PCDR1, 0, 6);
clk[IMX27_CLK_PER2_DIV] = imx_clk_divider("per2_div", "mpll_main2", CCM_PCDR1, 8, 6);
clk[IMX27_CLK_PER3_DIV] = imx_clk_divider("per3_div", "mpll_main2", CCM_PCDR1, 16, 6);
clk[IMX27_CLK_PER4_DIV] = imx_clk_divider("per4_div", "mpll_main2", CCM_PCDR1, 24, 6);
clk[IMX27_CLK_VPU_SEL] = imx_clk_mux("vpu_sel", CCM_CSCR, 21, 1, vpu_sel_clks, ARRAY_SIZE(vpu_sel_clks));
clk[IMX27_CLK_VPU_DIV] = imx_clk_divider("vpu_div", "vpu_sel", CCM_PCDR0, 10, 6);
clk[IMX27_CLK_USB_DIV] = imx_clk_divider("usb_div", "spll_gate", CCM_CSCR, 28, 3);
clk[IMX27_CLK_CPU_SEL] = imx_clk_mux("cpu_sel", CCM_CSCR, 15, 1, cpu_sel_clks, ARRAY_SIZE(cpu_sel_clks));
clk[IMX27_CLK_CLKO_SEL] = imx_clk_mux("clko_sel", CCM_CCSR, 0, 5, clko_sel_clks, ARRAY_SIZE(clko_sel_clks));
if (mx27_revision() >= IMX_CHIP_REVISION_2_0)
clk[IMX27_CLK_CPU_DIV] = imx_clk_divider("cpu_div", "cpu_sel", CCM_CSCR, 12, 2);
else
Annotation
- Immediate include surface: `linux/clk.h`, `linux/clk-provider.h`, `linux/clkdev.h`, `linux/err.h`, `linux/io.h`, `linux/of.h`, `linux/of_address.h`, `dt-bindings/clock/imx27-clock.h`.
- Detected declarations: `function _mx27_clocks_init`, `function mx27_clocks_init_dt`, `function for_each_compatible_node_scoped`.
- 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.