107 lines
2.3 KiB
C
107 lines
2.3 KiB
C
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/*
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* Joshua Henderson <joshua.henderson@microchip.com>
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* Copyright (C) 2015 Microchip Technology Inc. All rights reserved.
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*
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* This program is free software; you can distribute it and/or modify it
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* under the terms of the GNU General Public License (Version 2) as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*/
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#include <asm/mach-pic32/pic32.h>
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#include "pic32mzda.h"
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/* Oscillators, PLL & clocks */
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#define ICLK_MASK 0x00000080
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#define PLLDIV_MASK 0x00000007
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#define CUROSC_MASK 0x00000007
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#define PLLMUL_MASK 0x0000007F
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#define PB_MASK 0x00000007
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#define FRC1 0
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#define FRC2 7
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#define SPLL 1
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#define POSC 2
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#define FRC_CLK 8000000
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#define PIC32_POSC_FREQ 24000000
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#define OSCCON 0x0000
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#define SPLLCON 0x0020
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#define PB1DIV 0x0140
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u32 pic32_get_sysclk(void)
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{
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u32 osc_freq = 0;
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u32 pllclk;
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u32 frcdivn;
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u32 osccon;
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u32 spllcon;
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int curr_osc;
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u32 plliclk;
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u32 pllidiv;
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u32 pllodiv;
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u32 pllmult;
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u32 frcdiv;
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void __iomem *osc_base = ioremap(PIC32_BASE_OSC, 0x200);
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osccon = __raw_readl(osc_base + OSCCON);
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spllcon = __raw_readl(osc_base + SPLLCON);
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plliclk = (spllcon & ICLK_MASK);
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pllidiv = ((spllcon >> 8) & PLLDIV_MASK) + 1;
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pllodiv = ((spllcon >> 24) & PLLDIV_MASK);
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pllmult = ((spllcon >> 16) & PLLMUL_MASK) + 1;
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frcdiv = ((osccon >> 24) & PLLDIV_MASK);
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pllclk = plliclk ? FRC_CLK : PIC32_POSC_FREQ;
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frcdivn = ((1 << frcdiv) + 1) + (128 * (frcdiv == 7));
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if (pllodiv < 2)
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pllodiv = 2;
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else if (pllodiv < 5)
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pllodiv = (1 << pllodiv);
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else
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pllodiv = 32;
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curr_osc = (int)((osccon >> 12) & CUROSC_MASK);
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switch (curr_osc) {
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case FRC1:
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case FRC2:
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osc_freq = FRC_CLK / frcdivn;
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break;
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case SPLL:
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osc_freq = ((pllclk / pllidiv) * pllmult) / pllodiv;
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break;
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case POSC:
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osc_freq = PIC32_POSC_FREQ;
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break;
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default:
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break;
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}
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iounmap(osc_base);
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return osc_freq;
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}
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u32 pic32_get_pbclk(int bus)
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{
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u32 clk_freq;
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void __iomem *osc_base = ioremap(PIC32_BASE_OSC, 0x200);
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u32 pbxdiv = PB1DIV + ((bus - 1) * 0x10);
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u32 pbdiv = (__raw_readl(osc_base + pbxdiv) & PB_MASK) + 1;
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iounmap(osc_base);
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clk_freq = pic32_get_sysclk();
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return clk_freq / pbdiv;
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}
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