mirror of
https://github.com/apache/nuttx.git
synced 2026-06-07 09:18:00 +08:00
SAMA5: Add functions to calculate PLLACK, PCK, and MCK frequencies given the main clock frequency
This commit is contained in:
Gregory Nutt
@@ -94,8 +94,8 @@ CHIP_ASRCS =
|
||||
# SAMA5-specific C source files
|
||||
|
||||
CHIP_CSRCS = sam_allocateheap.c sam_boot.c sam_clockconfig.c sam_irq.c
|
||||
CHIP_CSRCS += sam_lowputc.c sam_memories.c sam_pck.c sam_pio.c sam_serial.c
|
||||
CHIP_CSRCS += sam_timerisr.c
|
||||
CHIP_CSRCS += sam_lowputc.c sam_memories.c sam_pck.c sam_pio.c sam_pmc.c
|
||||
CHIP_CSRCS += sam_serial.c sam_timerisr.c
|
||||
|
||||
# Configuration dependent C and assembly language files
|
||||
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
/************************************************************************************
|
||||
/****************************************************************************
|
||||
* arch/arm/src/sama5/sam_can.c
|
||||
*
|
||||
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
|
||||
@@ -41,7 +41,7 @@
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
************************************************************************************/
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Included Files
|
||||
|
||||
Executable
+238
@@ -0,0 +1,238 @@
|
||||
/****************************************************************************
|
||||
* arch/arm/src/sama5/sam_pmc.c
|
||||
*
|
||||
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
|
||||
* Author: Gregory Nutt <gnutt@nuttx.org>
|
||||
*
|
||||
* References:
|
||||
*
|
||||
* SAMA5D3 Series Data Sheet
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
* 3. Neither the name NuttX nor the names of its contributors may
|
||||
* be used to endorse or promote products derived from this software
|
||||
* without specific prior written permission.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||||
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||||
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||||
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||||
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||||
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Included Files
|
||||
****************************************************************************/
|
||||
|
||||
#include <nuttx/config.h>
|
||||
|
||||
#include <stdint.h>
|
||||
|
||||
#include <arch/board/board.h>
|
||||
|
||||
#include "up_arch.h"
|
||||
|
||||
#include "chip.h"
|
||||
#include "chip/sam_pmc.h"
|
||||
#include "sam_pmc.h"
|
||||
|
||||
/****************************************************************************
|
||||
* Pre-processor Definitions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Private Types
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Private Data
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Private Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Public Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_pllack_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the PPA output clock, PLLACK
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled. If the PLL is is disabled, either at the input divider
|
||||
* or the output multiplier, the value zero is returned.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_pllack_frequency(uint32_t mainclk)
|
||||
{
|
||||
uint32_t regval;
|
||||
uint32_t diva;
|
||||
uint32_t mula;
|
||||
uint32_t pllack;
|
||||
|
||||
/* Get the PLLA divider (DIVA) and multiplier (MULA) */
|
||||
|
||||
regval = getreg32(SAM_PMC_CKGR_PLLAR);
|
||||
|
||||
/* DIVA = 0: Divider output is 0
|
||||
* DIVA = 1: Divider is bypassed
|
||||
* DIVA = 2-255: Divider output is the selected clock divided by DIVA
|
||||
*/
|
||||
|
||||
diva = (regval & PMC_CKGR_PLLAR_DIV_MASK) >> PMC_CKGR_PLLAR_DIV_SHIFT;
|
||||
|
||||
pllack = mainclk;
|
||||
if (diva > 1)
|
||||
{
|
||||
pllack /= diva;
|
||||
}
|
||||
else if (diva < 1)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* MULA = 0: PLLA is deactivated
|
||||
* MULA > 0: The PLLA Clock frequency is the PLLA input frequency
|
||||
* multiplied by MULA + 1.
|
||||
*/
|
||||
|
||||
mula = (regval & PMC_CKGR_PLLAR_MUL_MASK) >> PMC_CKGR_PLLAR_MUL_SHIFT;
|
||||
if (mula > 1)
|
||||
{
|
||||
pllack *= (mula + 1);
|
||||
}
|
||||
else if (diva < 1)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
return pllack;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_pck_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the processor clock (PCK).
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled and the either the main clock or the PLLA output clock
|
||||
* (PLLACK) provides the input to the MCK prescaler.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_pck_frequency(uint32_t mainclk)
|
||||
{
|
||||
uint32_t regval;
|
||||
uint32_t pres;
|
||||
uint32_t pck;
|
||||
|
||||
/* Get the input source selection to the master/processor clock divider */
|
||||
|
||||
regval = getreg32(SAM_PMC_MCKR);
|
||||
switch (regval & PMC_MCKR_CSS_MASK)
|
||||
{
|
||||
case PMC_MCKR_CSS_MAIN: /* Main Clock */
|
||||
/* Use the Main Clock frequency */
|
||||
|
||||
pck = mainclk;
|
||||
break;
|
||||
|
||||
case PMC_MCKR_CSS_PLLA: /* PLLA Clock */
|
||||
/* Use the PLLA output clock */
|
||||
|
||||
pck = sam_pllack_frequency(mainclk);
|
||||
if (pck == 0)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Check if the PLLACK output is divided by 2 */
|
||||
|
||||
if ((regval & PMC_MCKR_PLLADIV2) != 0)
|
||||
{
|
||||
pck >>= 1;
|
||||
}
|
||||
break;
|
||||
|
||||
case PMC_MCKR_CSS_SLOW: /* Slow Clock */
|
||||
case PMC_MCKR_CSS_UPLL: /* UPLL Clock */
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Get the PCK frequency which is given by the selected input clock
|
||||
* divided by a power-of-two prescaler.
|
||||
*
|
||||
* PRES = 0: Selected clock
|
||||
* PRES = n > 0: Selected clock divided by 2**n
|
||||
*/
|
||||
|
||||
pres = (regval & PMC_MCKR_PRES_MASK) >> PMC_MCKR_PRES_SHIFT;
|
||||
return pck >> pres;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_mck_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the PPA output clock, PLLACK
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled and the either the main clock or the PLLA output clock
|
||||
* (PLLACK) provides the input to the MCK prescaler.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_mck_frequency(uint32_t mainclk)
|
||||
{
|
||||
uint32_t regval;
|
||||
uint32_t mdiv;
|
||||
uint32_t mck;
|
||||
|
||||
/* The MCK frequency is equivalent to the PCK clock frequency with an
|
||||
* additional divider.
|
||||
*/
|
||||
|
||||
mck = sam_pck_frequency(mainclk);
|
||||
if (mck == 0)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* MDIV = n: Master Clock is Prescaler Output Clock divided by (n + 1) */
|
||||
|
||||
regval = getreg32(SAM_PMC_MCKR);
|
||||
mdiv = (regval & PMC_MCKR_MDIV_MASK) >> PMC_MCKR_MDIV_SHIFT;
|
||||
if (mdiv > 0)
|
||||
{
|
||||
mck /= (mdiv + 1);
|
||||
}
|
||||
|
||||
return mck;
|
||||
}
|
||||
@@ -0,0 +1,115 @@
|
||||
/****************************************************************************
|
||||
* arch/arm/src/sama5/sam_pmc.h
|
||||
*
|
||||
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
|
||||
* Author: Gregory Nutt <gnutt@nuttx.org>
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
* 3. Neither the name NuttX nor the names of its contributors may be
|
||||
* used to endorse or promote products derived from this software
|
||||
* without specific prior written permission.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
||||
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
||||
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
||||
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
||||
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
||||
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
||||
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||
* POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef __ARCH_ARM_SRC_SAMA5_SAM_PMC_H
|
||||
#define __ARCH_ARM_SRC_SAMA5_SAM_PMC_H
|
||||
|
||||
/****************************************************************************
|
||||
* Included Files
|
||||
****************************************************************************/
|
||||
|
||||
#include <nuttx/config.h>
|
||||
|
||||
/****************************************************************************
|
||||
* Pre-processor Definitions
|
||||
****************************************************************************/
|
||||
|
||||
#ifndef __ASSEMBLY__
|
||||
|
||||
#undef EXTERN
|
||||
#if defined(__cplusplus)
|
||||
#define EXTERN extern "C"
|
||||
extern "C"
|
||||
{
|
||||
#else
|
||||
#define EXTERN extern
|
||||
#endif
|
||||
|
||||
/****************************************************************************
|
||||
* Public Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_pllack_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the PPA output clock, PLLACK
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled. If the PLL is is disabled, either at the input divider
|
||||
* or the output multiplier, the value zero is returned.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_pllack_frequency(uint32_t mainclk);
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_pck_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the processor clock (PCK).
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled and the either the main clock or the PLLA output clock
|
||||
* (PLLACK) provides the input to the MCK prescaler.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_pck_frequency(uint32_t mainclk);
|
||||
|
||||
/****************************************************************************
|
||||
* Name: sam_mck_frequency
|
||||
*
|
||||
* Description:
|
||||
* Given the Main Clock frequency that provides the input to PLLA, return
|
||||
* the frequency of the PPA output clock, PLLACK
|
||||
*
|
||||
* Assumptions:
|
||||
* PLLA is enabled and the either the main clock or the PLLA output clock
|
||||
* (PLLACK) provides the input to the MCK prescaler.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
uint32_t sam_mck_frequency(uint32_t mainclk);
|
||||
|
||||
#undef EXTERN
|
||||
#if defined(__cplusplus)
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* __ASSEMBLY__ */
|
||||
#endif /* __ARCH_ARM_SRC_SAMA5_SAM_PMC_H */
|
||||
Reference in New Issue
Block a user