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https://github.com/AsahiLinux/u-boot
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6cadaa046b
For the peripheral clock, provide the clock ops for the clock provider, such as spi0_clk. The .of_xlate is to get the clk->id, the .enable is to enable the spi0 peripheral clock, the .get_rate is to get the clock frequency. The driver for periph32ck node is responsible for recursively binding its children as clk devices, not provide the clock ops. So do the generated clock and system clock. Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com> Acked-by: Stephen Warren <swarren@nvidia.com>
85 lines
1.8 KiB
C
85 lines
1.8 KiB
C
/*
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* Copyright (C) 2016 Atmel Corporation
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* Wenyou.Yang <wenyou.yang@atmel.com>
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <clk-uclass.h>
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#include <dm/device.h>
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#include <linux/io.h>
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#include <mach/at91_pmc.h>
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#include "pmc.h"
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#define SYSTEM_MAX_ID 31
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/**
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* at91_system_clk_bind() - for the system clock driver
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* Recursively bind its children as clk devices.
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*
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* @return: 0 on success, or negative error code on failure
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*/
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static int at91_system_clk_bind(struct udevice *dev)
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{
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return at91_clk_sub_device_bind(dev, "system-clk");
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}
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static const struct udevice_id at91_system_clk_match[] = {
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{ .compatible = "atmel,at91rm9200-clk-system" },
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{}
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};
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U_BOOT_DRIVER(at91_system_clk) = {
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.name = "at91-system-clk",
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.id = UCLASS_MISC,
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.of_match = at91_system_clk_match,
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.bind = at91_system_clk_bind,
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};
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/*----------------------------------------------------------*/
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static inline int is_pck(int id)
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{
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return (id >= 8) && (id <= 15);
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}
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static int system_clk_enable(struct clk *clk)
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{
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struct pmc_platdata *plat = dev_get_platdata(clk->dev);
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struct at91_pmc *pmc = plat->reg_base;
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u32 mask;
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if (clk->id > SYSTEM_MAX_ID)
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return -EINVAL;
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mask = BIT(clk->id);
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writel(mask, &pmc->scer);
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/**
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* For the programmable clocks the Ready status in the PMC
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* status register should be checked after enabling.
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* For other clocks this is unnecessary.
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*/
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if (!is_pck(clk->id))
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return 0;
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while (!(readl(&pmc->sr) & mask))
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;
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return 0;
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}
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static struct clk_ops system_clk_ops = {
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.of_xlate = at91_clk_of_xlate,
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.enable = system_clk_enable,
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};
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U_BOOT_DRIVER(system_clk) = {
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.name = "system-clk",
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.id = UCLASS_CLK,
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.probe = at91_clk_probe,
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.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
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.ops = &system_clk_ops,
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};
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