vos/ambiq-hal-sys/ambiq-sparkfun-sdk/mcu/apollo/hal/am_hal_ios.c

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2022-10-24 06:45:43 +00:00
//*****************************************************************************
//
// am_hal_ios.c
//! @file
//!
//! @brief Functions for interfacing with the IO Slave module
//!
//! @addtogroup ios1 IO Slave (SPI/I2C)
//! @ingroup apollo1hal
//! @{
//
//*****************************************************************************
//*****************************************************************************
//
// Copyright (c) 2020, Ambiq Micro
// All rights reserved.
//
// 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 of the copyright holder nor the names of its
// contributors may be used to endorse or promote products derived from this
// software without specific prior written permission.
//
// Third party software included in this distribution is subject to the
// additional license terms as defined in the /docs/licenses directory.
//
// 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 HOLDER 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.
//
// This is part of revision 2.4.2 of the AmbiqSuite Development Package.
//
//*****************************************************************************
#include <stdint.h>
#include <stdbool.h>
#include "am_mcu_apollo.h"
//*****************************************************************************
//
// SRAM Buffer structure
//
//*****************************************************************************
typedef struct
{
uint8_t *pui8Data;
volatile uint32_t ui32WriteIndex;
volatile uint32_t ui32ReadIndex;
volatile uint32_t ui32Length;
uint32_t ui32Capacity;
}
am_hal_ios_buffer_t;
am_hal_ios_buffer_t g_sSRAMBuffer;
//*****************************************************************************
//
// Forward declarations of static funcitons.
//
//*****************************************************************************
static void am_hal_ios_buffer_init(am_hal_ios_buffer_t *psBuffer,
void *pvArray, uint32_t ui32Bytes);
static void fifo_write(uint8_t *pui8Data, uint32_t ui32NumBytes);
//*****************************************************************************
//
// Function-like macros.
//
//*****************************************************************************
#define am_hal_ios_buffer_empty(psBuffer) \
((psBuffer)->ui32Length == 0)
#define am_hal_ios_buffer_full(psBuffer) \
((psBuffer)->ui32Length == (psBuffer)->ui32Capacity)
#define am_hal_ios_buffer_data_left(psBuffer) \
((psBuffer)->ui32Length)
//*****************************************************************************
//
// Global Variables
//
//*****************************************************************************
volatile uint8_t * const am_hal_ios_pui8LRAM = (uint8_t *)REG_IOSLAVE_BASEADDR;
uint8_t *g_pui8FIFOBase = (uint8_t *) REG_IOSLAVE_BASEADDR;
uint8_t *g_pui8FIFOEnd = (uint8_t *) REG_IOSLAVE_BASEADDR;
uint8_t *g_pui8FIFOPtr = (uint8_t *) REG_IOSLAVE_BASEADDR;
uint8_t g_ui32HwFifoSize = 0;
uint32_t g_ui32FifoBaseOffset = 0;
//*****************************************************************************
//
//! @brief Enables the IOS module
//!
//! This function enables the IOSLAVE module using the IFCEN bitfield in the
//! IOSLAVE_CFG register.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_enable(uint32_t ui32Module)
{
AM_REGn(IOSLAVE, ui32Module, CFG) |= AM_REG_IOSLAVE_CFG_IFCEN(1);
}
//*****************************************************************************
//
//! @brief Disables the IOSLAVE module.
//!
//! This function disables the IOSLAVE module using the IFCEN bitfield in the
//! IOSLAVE_CFG register.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_disable(uint32_t ui32Module)
{
AM_REGn(IOSLAVE, ui32Module, CFG) &= ~(AM_REG_IOSLAVE_CFG_IFCEN(1));
}
//*****************************************************************************
//
//! @brief Configure the IOS module.
//!
//! This function reads the an \e am_hal_ios_config_t structure and uses it to
//! set up the IO Slave module. Please see the information on the configuration
//! structure for more information on the parameters that may be set by this
//! function.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_config(am_hal_ios_config_t *psConfig)
{
uint32_t ui32LRAMConfig;
//
// Record the FIFO parameters for later use.
//
g_pui8FIFOBase = (uint8_t *)(REG_IOSLAVE_BASEADDR + psConfig->ui32FIFOBase);
g_pui8FIFOEnd = (uint8_t *)(REG_IOSLAVE_BASEADDR + psConfig->ui32RAMBase);
g_ui32HwFifoSize = g_pui8FIFOEnd - g_pui8FIFOBase;
g_ui32FifoBaseOffset = psConfig->ui32FIFOBase;
//
// Calculate the value for the IO Slave FIFO configuration register.
//
ui32LRAMConfig = AM_REG_IOSLAVE_FIFOCFG_ROBASE(psConfig->ui32ROBase >> 3);
ui32LRAMConfig |= AM_REG_IOSLAVE_FIFOCFG_FIFOBASE(psConfig->ui32FIFOBase >> 3);
ui32LRAMConfig |= AM_REG_IOSLAVE_FIFOCFG_FIFOMAX(psConfig->ui32RAMBase >> 3);
//
// Just in case, disable the IOS
//
am_hal_ios_disable(0);
//
// Write the configuration register with the user's selected interface
// characteristics.
//
AM_REG(IOSLAVE, CFG) = psConfig->ui32InterfaceSelect;
//
// Write the FIFO configuration register to set the memory map for the LRAM.
//
AM_REG(IOSLAVE, FIFOCFG) = ui32LRAMConfig;
//
// Enable the IOS. The following configuration options can't be set while
// the IOS is disabled.
//
am_hal_ios_enable(0);
//
// Initialize the FIFO pointer to the beginning of the FIFO section.
//
am_hal_ios_fifo_ptr_set(psConfig->ui32FIFOBase);
//
// Write the FIFO threshold register.
//
AM_REG(IOSLAVE, FIFOTHR) = psConfig->ui32FIFOThreshold;
}
//*****************************************************************************
//
//! @brief Set bits in the HOST side IOINTCTL register.
//!
//! This function may be used to set an interrupt bit to the host.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_host_int_set(uint32_t ui32Interrupt)
{
//
// Set a bit that will cause an interrupt to the host.
//
AM_REG(IOSLAVE, IOINTCTL) = AM_REG_IOSLAVE_IOINTCTL_IOINTSET(ui32Interrupt);
}
//*****************************************************************************
//
//! @brief Clear bits in the HOST side IOINTCTL register.
//!
//! This function may be used to clear an interrupt bit to the host.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_host_int_clear(uint32_t ui32Interrupt)
{
//
// Clear bits that will cause an interrupt to the host.
//
AM_REG(IOSLAVE, IOINTCTL) = AM_REG_IOSLAVE_IOINTCTL_IOINTCLR(ui32Interrupt);
}
//*****************************************************************************
//
//! @brief Get the bits in the HOST side IOINTCTL register.
//!
//! This function may be used to read the host side interrupt bits.
//!
//! @return None.
//
//*****************************************************************************
uint32_t
am_hal_ios_host_int_get(void)
{
//
// return the value of the bits that will cause an interrupt to the host.
//
return AM_BFR(IOSLAVE, IOINTCTL, IOINT);
}
//*****************************************************************************
//
//! @brief Get the enable bits in the HOST side IOINTCTL register.
//!
//! This function may be used to read the host side interrupt bits.
//!
//! @return None.
//
//*****************************************************************************
uint32_t
am_hal_ios_host_int_enable_get(void)
{
//
// return the value of the bits that will cause an interrupt to the host.
//
return AM_BFR(IOSLAVE, IOINTCTL, IOINTEN);
}
//*****************************************************************************
//
//! @brief Enable an IOS Access Interrupt.
//!
//! This function may be used to enable an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_access_int_enable(uint32_t ui32Interrupt)
{
//
// OR the desired interrupt into the enable register.
//
AM_REG(IOSLAVE, REGACCINTEN) |= ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Return all enabled IOS Access Interrupts.
//!
//! This function may be used to return all enabled IOS Access interrupts.
//!
//! @return the enabled interrrupts.
//
//*****************************************************************************
uint32_t
am_hal_ios_access_int_enable_get(void)
{
//
// Return the enabled interrupts.
//
return AM_REG(IOSLAVE, REGACCINTEN);
}
//*****************************************************************************
//
//! @brief Disable an IOS Access Interrupt.
//!
//! This function may be used to disable an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_access_int_disable(uint32_t ui32Interrupt)
{
//
// Clear the desired bit from the interrupt enable register.
//
AM_REG(IOSLAVE, REGACCINTEN) &= ~(ui32Interrupt);
}
//*****************************************************************************
//
//! @brief Clear an IOS Access Interrupt.
//!
//! This function may be used to clear an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_access_int_clear(uint32_t ui32Interrupt)
{
//
// Use the interrupt clear register to deactivate the chosen interrupt.
//
AM_REG(IOSLAVE, REGACCINTCLR) = ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Set an IOS Access Interrupt.
//!
//! This function may be used to set an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_access_int_set(uint32_t ui32Interrupt)
{
//
// Use the interrupt set register to activate the chosen interrupt.
//
AM_REG(IOSLAVE, REGACCINTSET) = ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Check the status of an IOS Access Interrupt.
//!
//! @param bEnabledOnly - return only the enabled interrupt status.
//!
//! This function may be used to return the enabled interrupt status.
//!
//! @return the enabled interrupt status.
//
//*****************************************************************************
uint32_t
am_hal_ios_access_int_status_get(bool bEnabledOnly)
{
if (bEnabledOnly)
{
uint32_t u32RetVal = AM_REG(IOSLAVE, REGACCINTSTAT);
return u32RetVal & AM_REG(IOSLAVE, REGACCINTEN);
}
else
{
return AM_REG(IOSLAVE, REGACCINTSTAT);
}
}
//*****************************************************************************
//
//! @brief Enable an IOS Interrupt.
//!
//! @param ui32Interrupt - desired interrupts.
//!
//! This function may be used to enable an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_int_enable(uint32_t ui32Interrupt)
{
//
// OR the desired interrupt into the enable register.
//
AM_REG(IOSLAVE, INTEN) |= ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Return all enabled IOS Interrupts.
//!
//! This function may be used to return all enabled IOS interrupts.
//!
//! @return the enabled interrrupts.
//
//*****************************************************************************
uint32_t
am_hal_ios_int_enable_get(void)
{
//
// Return the enabled interrupts.
//
return AM_REG(IOSLAVE, INTEN);
}
//*****************************************************************************
//
//! @brief Disable an IOS Interrupt.
//!
//! @param ui32Interrupt - desired interrupts.
//!
//! This function may be used to disable an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_int_disable(uint32_t ui32Interrupt)
{
//
// Clear the desired bit from the interrupt enable register.
//
AM_REG(IOSLAVE, INTEN) &= ~(ui32Interrupt);
}
//*****************************************************************************
//
//! @brief Clear an IOS Interrupt.
//!
//! @param ui32Interrupt - desired interrupts.
//!
//! This function may be used to clear an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_int_clear(uint32_t ui32Interrupt)
{
//
// Use the interrupt clear register to deactivate the chosen interrupt.
//
AM_REG(IOSLAVE, INTCLR) = ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Set an IOS Interrupt.
//!
//! @param ui32Interrupt - desired interrupts.
//!
//! This function may be used to set an interrupt to the NVIC.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_int_set(uint32_t ui32Interrupt)
{
//
// Use the interrupt clear register to deactivate the chosen interrupt.
//
AM_REG(IOSLAVE, INTSET) = ui32Interrupt;
}
//*****************************************************************************
//
//! @brief Write to the LRAM.
//!
//! @param ui32Offset - offset into the LRAM to write.
//! @param ui8Value - value to be written.
//!
//! This function writes ui8Value to offset ui32Offset inside the LRAM.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_lram_write(uint32_t ui32Offset, uint8_t ui8Value)
{
//
// Write the LRAM.
//
am_hal_ios_pui8LRAM[ui32Offset] = ui8Value;
}
//*****************************************************************************
//
//! @brief Read from the LRAM.
//!
//! @param ui32Offset - offset into the LRAM to read.
//!
//! This function read from offset ui32Offset inside the LRAM.
//!
//! @return the value at ui32Offset.
//
//*****************************************************************************
uint8_t
am_hal_ios_lram_read(uint32_t ui32Offset)
{
//
// Read the LRAM.
//
return am_hal_ios_pui8LRAM[ui32Offset];
}
//*****************************************************************************
//
//! @brief Check the status of an IOS Interrupt.
//!
//! @param bEnabledOnly - return only the enabled interrupt status.
//!
//! This function may be used to return the enabled interrupt status.
//!
//! @return the enabled interrupt status.
//
//*****************************************************************************
uint32_t
am_hal_ios_int_status_get(bool bEnabledOnly)
{
if (bEnabledOnly)
{
uint32_t u32RetVal = AM_REG(IOSLAVE, INTSTAT);
return u32RetVal & AM_REG(IOSLAVE, INTEN);
}
else
{
return AM_REG(IOSLAVE, INTSTAT);
}
}
//*****************************************************************************
//
//! @brief Check the amount of space used in the FIFO
//!
//! This function returns the available data in the overall FIFO yet to be
//! read by the host. This takes into account the SRAM buffer and hardware FIFO
//!
//! @return Bytes used in the Overall FIFO.
//
//*****************************************************************************
uint32_t
am_hal_ios_fifo_space_used(void)
{
uint32_t ui32Val;
uint32_t ui32Primask;
//
// Start a critical section for thread safety.
//
ui32Primask = am_hal_interrupt_master_disable();
ui32Val = g_sSRAMBuffer.ui32Length;
ui32Val += AM_BFR(IOSLAVE, FIFOPTR, FIFOSIZ);
//
// End the critical section
//
am_hal_interrupt_master_set(ui32Primask);
return ui32Val;
}
//*****************************************************************************
//
//! @brief Check the amount of space left in the FIFO
//!
//! This function returns the available space in the overall FIFO to accept
//! new data. This takes into account the SRAM buffer and hardware FIFO
//!
//! @return Bytes left in the Overall FIFO.
//
//*****************************************************************************
uint32_t
am_hal_ios_fifo_space_left(void)
{
uint32_t ui32Val;
uint32_t ui32Primask;
//
// Start a critical section for thread safety.
//
ui32Primask = am_hal_interrupt_master_disable();
//
// We waste one byte in HW FIFO
//
ui32Val = g_sSRAMBuffer.ui32Capacity + g_ui32HwFifoSize - 1;
ui32Val -= g_sSRAMBuffer.ui32Length;
ui32Val -= AM_BFR(IOSLAVE, FIFOPTR, FIFOSIZ);
//
// End the critical section
//
am_hal_interrupt_master_set(ui32Primask);
return ui32Val;
}
//*****************************************************************************
//
//! @brief Check the amount of space left in the hardware FIFO
//!
//! This function reads the IOSLAVE FIFOPTR register and determines the amount
//! of space left in the IOS LRAM FIFO.
//!
//! @return Bytes left in the IOS FIFO.
//
//*****************************************************************************
static uint32_t
fifo_space_left(void)
{
//
// We waste one byte in HW FIFO
//
return ((uint32_t)g_ui32HwFifoSize- AM_BFR(IOSLAVE, FIFOPTR, FIFOSIZ) - 1);
}
//*****************************************************************************
//
// Helper function for managing IOS FIFO writes.
//
//*****************************************************************************
static void
fifo_write(uint8_t *pui8Data, uint32_t ui32NumBytes)
{
while ( ui32NumBytes )
{
//
// Write the data to the FIFO
//
*g_pui8FIFOPtr++ = *pui8Data++;
ui32NumBytes--;
//
// Make sure to wrap the FIFO pointer if necessary.
//
if ( g_pui8FIFOPtr == g_pui8FIFOEnd )
{
g_pui8FIFOPtr = g_pui8FIFOBase;
}
}
}
//
// Assembly code below assumes 8bit FIFOSIZ field aligned at a byte boundary
//
#if (((AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_M >> AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S) != 0xFF) \
|| (AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S & 0x3))
#error "FIFOSIZ not 8bit value aligned at byte offset"
#endif
//
// Byte offset of FIFOSIZ field in FIFOPTR register
//
#define BYTEOFFSET_FIFOSIZE (AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S >> 3)
//*****************************************************************************
//
// Helper function in assembly for implementing the ReSync
//
//*****************************************************************************
#if (defined (__ARMCC_VERSION)) && (__ARMCC_VERSION < 6000000)
__asm static void
internal_resync_fifoSize(uint32_t wrOffset, uint32_t maxFifoSize, uint32_t hwFifoPtrRegAddr)
{
push {r3, r4} // Save r3, r4 - used by this function
internal_resync_fifoSize_loop
ldr r4, [r2] // Load FIFOPTR register in r4
ubfx r3, r4, #AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S, #8 // Extract hwFifoSize to r3
uxtb r4, r4 // Extract rdOffset in r4
subs r4, r0, r4 // fifoSize in r4 = wrOffset - rdOffset
it cc // if (wrOffset < rdOffset),
addcc r4, r4, r1 // fifoSize = maxFifoSize - (rdOffset - wrOffset)
cmp r3, r4 // (hwFifoSize != fifoSize)
beq internal_resync_fifosize_done
strb r4, [r2, #1] // Overwrite FIFOSIZ value with fifoSize
b internal_resync_fifoSize_loop // Repeat the check
internal_resync_fifosize_done
pop {r3, r4} // Restore registers
bx lr
}
#elif (defined (__ARMCC_VERSION)) && (__ARMCC_VERSION >= 6000000)
#if (AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S != 8)
#error "AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S not 8"
#endif
__attribute__((naked))
static void
internal_resync_fifoSize(uint32_t wrOffset, uint32_t maxFifoSize, uint32_t hwFifoPtrRegAddr)
{
__asm
(
" push {r3,r4}\n\t" // Save r3, r4 - used by this function
"__internal_resync_fifoSize_loop:\n\t"
" ldr r4, [r2]\n\t" // Load FIFOPTR register in r4
" ubfx r3, r4, #8, #8\n\t" // Extract hwFifoSize to r3
" uxtb r4, r4\n\t" // Extract rdOffset in r4
" subs r4, r0, r4\n\t" // fifoSize in r4 = wrOffset - rdOffset
" it cc\n\t" // if (wrOffset < rdOffset)
" addcc r4, r4, r1\n\t" // fifoSize = maxFifoSize - (rdOffset - wrOffset)
" cmp r3, r4\n\t" // (hwFifoSize != fifoSize)
" beq __internal_resync_fifosize_done\n\t"
" strb r4, [r2, #1]\n\t" // Overwrite FIFOSIZ value with fifoSize
" b __internal_resync_fifoSize_loop\n\t" // Repeat the check
"__internal_resync_fifosize_done:\n\t"
" pop {r3,r4}\n\t" // Restore registers
" bx lr\n\t"
);
}
#elif defined(__GNUC_STDC_INLINE__)
#if (AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S != 8)
#error "AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S not 8"
#endif
__attribute__((naked))
static void
internal_resync_fifoSize(uint32_t wrOffset, uint32_t maxFifoSize, uint32_t hwFifoPtrRegAddr)
{
__asm
(
" push {r3,r4}\n\t" // Save r3, r4 - used by this function
"__internal_resync_fifoSize_loop:\n\t"
" ldr r4, [r2]\n\t" // Load FIFOPTR register in r4
" ubfx r3, r4, #8, #8\n\t" // Extract hwFifoSize to r3
" uxtb r4, r4\n\t" // Extract rdOffset in r4
" subs r4, r0, r4\n\t" // fifoSize in r4 = wrOffset - rdOffset
" it cc\n\t" // if (wrOffset < rdOffset)
" addcc r4, r4, r1\n\t" // fifoSize = maxFifoSize - (rdOffset - wrOffset)
" cmp r3, r4\n\t" // (hwFifoSize != fifoSize)
" beq __internal_resync_fifosize_done\n\t"
" strb r4, [r2, #1]\n\t" // Overwrite FIFOSIZ value with fifoSize
" b __internal_resync_fifoSize_loop\n\t" // Repeat the check
"__internal_resync_fifosize_done:\n\t"
" pop {r3,r4}\n\t" // Restore registers
" bx lr\n\t"
);
}
#elif defined(__IAR_SYSTEMS_ICC__)
#if (AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S != 8)
#error "AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S not 8"
#endif
__stackless static void
internal_resync_fifoSize(uint32_t wrOffset, uint32_t maxFifoSize, uint32_t hwFifoPtrRegAddr)
{
__asm volatile (
" push {r3,r4}\n" // Save r3, r4 - used by this function
"__internal_resync_fifoSize_loop:\n"
" ldr r4, [r2]\n" // Load FIFOPTR register in r4
" ubfx r3, r4, #8, #8\n" // Extract hwFifoSize to r3
" uxtb r4, r4\n" // Extract rdOffset in r4
" subs r4, r0, r4\n" // fifoSize in r4 = wrOffset - rdOffset
" it cc\n"
" addcc r4, r4, r1\n" // fifoSize = maxFifoSize - (rdOffset - wrOffset)
" cmp r3, r4\n" // (fifoSize != hwFifoSize)
" beq __internal_resync_fifosize_done\n"
" strb r4, [r2, #1]\n" // Overwrite FIFOSIZ value with fifoSize
" b __internal_resync_fifoSize_loop\n" // Repeat the check
"__internal_resync_fifosize_done:\n"
" pop {r3,r4}\n" // Restore registers
" bx lr\n"
);
}
#else
static void
internal_resync_fifoSize(uint32_t wrOffset, uint32_t maxFifoSize, uint32_t hwFifoPtrRegAddr)
{
uint32_t fifoSize;
uint32_t hwFifoPtrReg;
uint32_t rdOffset;
uint32_t hwFifoSize;
hwFifoPtrReg = AM_REGVAL(hwFifoPtrRegAddr);
rdOffset = ((hwFifoPtrReg & AM_REG_IOSLAVE_FIFOPTR_FIFOPTR_M) >> AM_REG_IOSLAVE_FIFOPTR_FIFOPTR_S);
hwFifoSize = (hwFifoPtrReg & AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_M) >> AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S;
// By wasting one byte in hardware FIFO, we're guaranteed that fifoSize does not need special handling for FULL FIFO case
fifoSize = ((wrOffset >= rdOffset) ? (wrOffset - rdOffset) : (maxFifoSize - (rdOffset - wrOffset)));
while (fifoSize != hwFifoSize)
{
// Overwite correct FIFOSIZ
// Need to do a Byte Write to make sure the FIFOPTR is not overwritten
*((uint8_t *)(hwFifoPtrRegAddr + BYTEOFFSET_FIFOSIZE)) = fifoSize;
// Read back the register and check for consistency
hwFifoPtrReg = AM_REGVAL(hwFifoPtrRegAddr);
rdOffset = ((hwFifoPtrReg & AM_REG_IOSLAVE_FIFOPTR_FIFOPTR_M) >> AM_REG_IOSLAVE_FIFOPTR_FIFOPTR_S);
hwFifoSize = (hwFifoPtrReg & AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_M) >> AM_REG_IOSLAVE_FIFOPTR_FIFOSIZ_S;
// By wasting one byte in hardware FIFO, we're guaranteed that fifoSize does not need special handling for FULL FIFO case
fifoSize = ((wrOffset >= rdOffset) ? (wrOffset - rdOffset) : (hwFifoSize - (rdOffset - wrOffset)));
}
}
#endif
//
// Address of the FIFOPTR register
//
#define AM_REG_IOS_FIFOPTR (REG_IOSLAVE_BASEADDR + AM_REG_IOSLAVE_FIFOPTR_O)
// When the FIFO is being replenished by the SW, at the same time as host is
// reading from it, there is a possible race condition, where the hardware decrement
// of FIFOSIZ as a result of read gets overwritten by hardware increment due to
// write.
// This function re-sync's the FIFOSIZ to ensure such errors do not accumulate
void
resync_fifoSize(void)
{
uint32_t ui32Primask;
uint32_t wrOffset = (uint32_t)g_pui8FIFOPtr - (uint32_t)am_hal_ios_pui8LRAM;
//
// Start a critical section for thread safety.
//
ui32Primask = am_hal_interrupt_master_disable();
internal_resync_fifoSize(wrOffset, g_ui32HwFifoSize, AM_REG_IOS_FIFOPTR);
// Clear interrupts for IOS which could be spuriously triggered
AM_REG(IOSLAVE, REGACCINTCLR) = (AM_HAL_IOS_INT_FSIZE | AM_HAL_IOS_INT_FOVFL | AM_HAL_IOS_INT_FUNDFL);
//
// End the critical section
//
am_hal_interrupt_master_set(ui32Primask);
return;
}
//*****************************************************************************
//
//! @brief Transfer any available data from the IOS SRAM buffer to the FIFO.
//!
//! This function is meant to be called from an interrupt handler for the
//! ioslave module. It checks the IOS FIFO interrupt status for a threshold
//! event, and transfers data from an SRAM buffer into the IOS FIFO.
//!
//! @param ui32Status should be set to the ios interrupt status at the time of
//! ISR entry.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_fifo_service(uint32_t ui32Status)
{
uint32_t thresh;
uint32_t freeSpace, usedSpace, chunk1, chunk2, ui32WriteIndex;
//
// Check for FIFO size interrupts.
//
if ( ui32Status & AM_HAL_IOS_INT_FSIZE )
{
thresh = AM_BFR(IOSLAVE, FIFOTHR, FIFOTHR);
//
// While the FIFO is at or below threshold Add more data
// If Fifo level is above threshold, we're guaranteed an FSIZ interrupt
//
while (g_sSRAMBuffer.ui32Length &&
((usedSpace = AM_BFR(IOSLAVE, FIFOPTR, FIFOSIZ)) <= thresh) )
{
//
// So, we do have some data in SRAM which needs to be moved to FIFO.
// A chunk of data is a continguous set of bytes in SRAM that can be
// written to FIFO. Determine the chunks of data from SRAM that can
// be written. Up to two chunks possible
//
ui32WriteIndex = g_sSRAMBuffer.ui32WriteIndex;
chunk1 = ((ui32WriteIndex > (uint32_t)g_sSRAMBuffer.ui32ReadIndex) ? \
(ui32WriteIndex - (uint32_t)g_sSRAMBuffer.ui32ReadIndex) : \
(g_sSRAMBuffer.ui32Capacity - (uint32_t)g_sSRAMBuffer.ui32ReadIndex));
chunk2 = g_sSRAMBuffer.ui32Length - chunk1;
// We waste one byte in HW FIFO
freeSpace = g_ui32HwFifoSize - usedSpace - 1;
// Write data in chunks
// Determine the chunks of data from SRAM that can be written
if (chunk1 > freeSpace)
{
fifo_write((uint8_t *)(g_sSRAMBuffer.pui8Data + g_sSRAMBuffer.ui32ReadIndex), freeSpace);
//
// Advance the read index, wrapping if needed.
//
g_sSRAMBuffer.ui32ReadIndex += freeSpace;
// No need to check for wrap as we wrote less than chunk1
//
// Adjust the length value to reflect the change.
//
g_sSRAMBuffer.ui32Length -= freeSpace;
}
else
{
fifo_write((uint8_t *)(g_sSRAMBuffer.pui8Data + g_sSRAMBuffer.ui32ReadIndex), chunk1);
//
// Update the read index - wrapping as needed
//
g_sSRAMBuffer.ui32ReadIndex += chunk1;
g_sSRAMBuffer.ui32ReadIndex %= g_sSRAMBuffer.ui32Capacity;
//
// Adjust the length value to reflect the change.
//
g_sSRAMBuffer.ui32Length -= chunk1;
freeSpace -= chunk1;
if (freeSpace && chunk2)
{
if (chunk2 > freeSpace)
{
fifo_write((uint8_t *)(g_sSRAMBuffer.pui8Data + g_sSRAMBuffer.ui32ReadIndex), freeSpace);
//
// Advance the read index, wrapping if needed.
//
g_sSRAMBuffer.ui32ReadIndex += freeSpace;
// No need to check for wrap in chunk2
//
// Adjust the length value to reflect the change.
//
g_sSRAMBuffer.ui32Length -= freeSpace;
}
else
{
fifo_write((uint8_t *)(g_sSRAMBuffer.pui8Data + g_sSRAMBuffer.ui32ReadIndex), chunk2);
//
// Advance the read index, wrapping if needed.
//
g_sSRAMBuffer.ui32ReadIndex += chunk2;
// No need to check for wrap in chunk2
//
// Adjust the length value to reflect the change.
//
g_sSRAMBuffer.ui32Length -= chunk2;
}
}
}
resync_fifoSize();
//
// Need to retake the FIFO space, after Threshold interrupt has been reenabled
// Clear any spurious FSIZE interrupt that might have got raised
//
AM_BFW(IOSLAVE, INTCLR, FSIZE, 1);
}
}
}
//*****************************************************************************
//
//! @brief Writes the specified number of bytes to the IOS fifo.
//!
//! @param pui8Data is a pointer to the data to be written to the fifo.
//! @param ui32NumBytes is the number of bytes to send.
//!
//! This function will write data from the caller-provided array to the IOS
//! LRAM FIFO. If there is no space in the LRAM FIFO, the data will be copied
//! to a temporary SRAM buffer instead.
//!
//! The maximum message size for the IO Slave is 1023 bytes.
//!
//! @note In order for SRAM copy operations in the function to work correctly,
//! the \e am_hal_ios_buffer_service() function must be called in the ISR for
//! the ioslave module.
//!
//! @return Number of bytes written (could be less than ui32NumBytes, if not enough space)
//
//*****************************************************************************
uint32_t
am_hal_ios_fifo_write(uint8_t *pui8Data, uint32_t ui32NumBytes)
{
uint32_t ui32FIFOSpace;
uint32_t ui32SRAMSpace;
uint32_t ui32SRAMLength;
uint32_t ui32Primask;
uint32_t totalBytes = ui32NumBytes;
//
// This operation will only work properly if an SRAM buffer has been
// allocated. Make sure that am_hal_ios_fifo_buffer_init() has been called,
// and the buffer pointer looks valid.
//
am_hal_debug_assert(g_sSRAMBuffer.pui8Data != 0);
if ( ui32NumBytes == 0)
{
return 0;
}
//
// Start a critical section for thread safety.
//
ui32Primask = am_hal_interrupt_master_disable();
ui32SRAMLength = g_sSRAMBuffer.ui32Length;
//
// End the critical section
//
am_hal_interrupt_master_set(ui32Primask);
//
// If the SRAM buffer is empty, we should just write directly to the FIFO.
//
if (ui32SRAMLength == 0)
{
ui32FIFOSpace = fifo_space_left();
//
// If the whole message fits, send it now.
//
if ( ui32NumBytes <= ui32FIFOSpace )
{
fifo_write(pui8Data, ui32NumBytes);
ui32NumBytes = 0;
}
else
{
fifo_write(pui8Data, ui32FIFOSpace);
ui32NumBytes -= ui32FIFOSpace;
pui8Data += ui32FIFOSpace;
};
resync_fifoSize();
}
//
// If there's still data, write it to the SRAM buffer.
//
if ( ui32NumBytes )
{
uint32_t idx, writeIdx, capacity, fifoSize;
ui32SRAMSpace = g_sSRAMBuffer.ui32Capacity - ui32SRAMLength;
writeIdx = g_sSRAMBuffer.ui32WriteIndex;
capacity = g_sSRAMBuffer.ui32Capacity;
//
// Make sure that the data will fit inside the SRAM buffer.
//
if ( ui32SRAMSpace > ui32NumBytes )
{
ui32SRAMSpace = ui32NumBytes;
}
//
// If the data will fit, write it to the SRAM buffer.
//
for (idx = 0; idx < ui32SRAMSpace; idx++)
{
g_sSRAMBuffer.pui8Data[(idx + writeIdx) % capacity] = pui8Data[idx];
}
ui32NumBytes -= idx;
//
// Start a critical section for thread safety before updating length & wrIdx.
//
ui32Primask = am_hal_interrupt_master_disable();
//
// Advance the write index, making sure to wrap if necessary.
//
g_sSRAMBuffer.ui32WriteIndex = (idx + writeIdx) % capacity;
//
// Update the length value appropriately.
//
g_sSRAMBuffer.ui32Length += idx;
//
// End the critical section
//
am_hal_interrupt_master_set(ui32Primask);
// It is possible that there is a race condition that the FIFO level has
// gone below the threshold by the time we set the wrIdx above, and hence
// we may never get the threshold interrupt to serve the SRAM data we
// just wrote
// If that is the case, explicitly generate the FSIZE interrupt from here
fifoSize = AM_BFR(IOSLAVE, FIFOPTR, FIFOSIZ);
if (fifoSize <= AM_BFR(IOSLAVE, FIFOTHR, FIFOTHR))
{
AM_BFW(IOSLAVE, INTSET, FSIZE, 1);
}
}
return (totalBytes - ui32NumBytes);
}
//*****************************************************************************
//
//! @brief Writes the specified number of bytes to the IOS fifo simply.
//!
//! @param pui8Data is a pointer to the data to be written to the fifo.
//! @param ui32NumBytes is the number of bytes to send.
//!
//! This function will write data from the caller-provided array to the IOS
//! LRAM FIFO. This simple routine does not use SRAM buffering for large
//! messages.
//!
//! The maximum message size for the IO Slave is 128 bytes.
//!
//! @note Do note call the \e am_hal_ios_buffer_service() function in the ISR for
//! the ioslave module.
//!
//! @return
//
//*****************************************************************************
void
am_hal_ios_fifo_write_simple(uint8_t *pui8Data, uint32_t ui32NumBytes)
{
uint32_t ui32FIFOSpace;
//
// Check the FIFO and the SRAM buffer to see where we have space.
//
ui32FIFOSpace = fifo_space_left();
//
// If the whole message fits, send it now.
//
if ( ui32NumBytes <= ui32FIFOSpace )
{
fifo_write(pui8Data, ui32NumBytes);
}
else
{
//
// The message didn't fit. Try using am_hal_ios_fifo_write() instead.
//
am_hal_debug_assert_msg(0, "The requested IOS transfer didn't fit in"
"the LRAM FIFO. Try using am_hal_ios_fifo_write().");
}
}
//*****************************************************************************
//
//! @brief Sets the IOS FIFO pointer to the specified LRAM offset.
//!
//! @param ui32Offset is LRAM offset to set the FIFO pointer to.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_fifo_ptr_set(uint32_t ui32Offset)
{
uint32_t ui32Primask;
//
// Start a critical section for thread safety.
//
ui32Primask = am_hal_interrupt_master_disable();
//
// Set the FIFO Update bit.
//
AM_REG(IOSLAVE, FUPD) = 0x1;
//
// Change the FIFO offset.
//
AM_REG(IOSLAVE, FIFOPTR) = ui32Offset;
//
// Clear the FIFO update bit.
//
AM_REG(IOSLAVE, FUPD) = 0x0;
//
// Set the global FIFO-pointer tracking variable.
//
g_pui8FIFOPtr = (uint8_t *) (REG_IOSLAVE_BASEADDR + ui32Offset);
//
// End the critical section.
//
am_hal_interrupt_master_set(ui32Primask);
}
//*****************************************************************************
//
// Initialize an SRAM buffer for use with the IO Slave.
//
//*****************************************************************************
static void
am_hal_ios_buffer_init(am_hal_ios_buffer_t *psBuffer, void *pvArray,
uint32_t ui32Bytes)
{
psBuffer->ui32WriteIndex = 0;
psBuffer->ui32ReadIndex = 0;
psBuffer->ui32Length = 0;
psBuffer->ui32Capacity = ui32Bytes;
psBuffer->pui8Data = (uint8_t *)pvArray;
}
//*****************************************************************************
//
//! @brief Poll for all host side read activity to complete.
//!
//! Poll for all host side read activity to complete. Use this before
//! calling am_hal_ios_fifo_write_simple().
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_read_poll_complete(void)
{
while ( AM_REG(IOSLAVE, FUPD) & AM_REG_IOSLAVE_FUPD_IOREAD_M );
}
//*****************************************************************************
//
//! @brief Initializes an SRAM buffer for the IOS FIFO.
//!
//! @param pui8Buffer is the SRAM buffer that will be used for IOS fifo data.
//! @param ui32BufferSize is the size of the SRAM buffer.
//!
//! This function provides the IOS HAL functions with working memory for
//! managing outgoing IOS FIFO transactions. It needs to be called at least
//! once before am_hal_ios_fifo_write() may be used.
//!
//! The recommended buffer size for the IOS FIFO is 1024 bytes.
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_fifo_buffer_init(uint8_t *pui8Buffer, uint32_t ui32NumBytes)
{
//
// Initialize the global SRAM buffer
// Total size, which is SRAM Buffer plus the hardware FIFO needs to be
// limited to 1023
//
if (ui32NumBytes > (1023 - g_ui32HwFifoSize + 1))
{
ui32NumBytes = (1023 - g_ui32HwFifoSize + 1);
}
am_hal_ios_buffer_init(&g_sSRAMBuffer, pui8Buffer, ui32NumBytes);
//
// Clear the FIFO State
//
AM_BFW(IOSLAVE, FIFOCTR, FIFOCTR, 0x0);
AM_BFW(IOSLAVE, FIFOPTR, FIFOSIZ, 0x0);
am_hal_ios_fifo_ptr_set(g_ui32FifoBaseOffset);
}
//*****************************************************************************
//
//! @brief Update the FIFOCTR to inform host of available data to read.
//!
//! This function allows the application to indicate to HAL when it is safe to
//! update the FIFOCTR.
//!
//! Application needs to implement some sort of
//! synchronization with the host to make sure host is not reading FIFOCTR while
//! it is being updated by the MCU, since the FIFOCTR read over
//! IO is not an atomic operation.
//!
//!
//! @return None.
//
//*****************************************************************************
void
am_hal_ios_update_fifoctr(void)
{
uint32_t ui32Val;
// Determine the available data
ui32Val = am_hal_ios_fifo_space_used();
// Update FIFOCTR
AM_BFW(IOSLAVE, FIFOCTR, FIFOCTR, ui32Val);
return;
}
//*****************************************************************************
//
// End the doxygen group
//! @}
//
//*****************************************************************************