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NerdNos-Firmware/lib/TFT_eSPI/Processors/TFT_eSPI_RP2040.h

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changed: - added plaformio libraries - improvements and fix errors. Please enter the commit message for your changes. Lines starting
2023-04-17 02:07:18 +02:00
////////////////////////////////////////////////////
// TFT_eSPI generic driver functions //
////////////////////////////////////////////////////
// This is a generic driver for Arduino boards, it supports SPI interface displays
// 8 bit parallel interface to TFT is not supported for generic processors
#ifndef _TFT_eSPI_RP2040H_
#define _TFT_eSPI_RP2040H_
#ifndef ARDUINO_ARCH_MBED
#include <LittleFS.h>
#define FONT_FS_AVAILABLE
#define SPIFFS LittleFS
#endif
// Required for both the official and community board packages
#include "hardware/dma.h"
#include "hardware/pio.h"
#include "hardware/clocks.h"
// Processor ID reported by getSetup()
#define PROCESSOR_ID 0x2040
// Transactions always supported
#ifndef SUPPORT_TRANSACTIONS
#define SUPPORT_TRANSACTIONS
#endif
// Include processor specific header
// None
#if defined (TFT_PARALLEL_8_BIT) || defined (TFT_PARALLEL_16_BIT) || defined (RP2040_PIO_SPI)
#define RP2040_PIO_INTERFACE
#define RP2040_PIO_PUSHBLOCK
#endif
#if !defined (RP2040_PIO_INTERFACE)// SPI
// Use SPI0 as default if not defined
#ifndef TFT_SPI_PORT
#define TFT_SPI_PORT 0
#endif
#if (TFT_SPI_PORT == 0)
#define SPI_X spi0
#else
#define SPI_X spi1
#endif
// Processor specific code used by SPI bus transaction begin/end_tft_write functions
#define SET_BUS_WRITE_MODE spi_set_format(SPI_X, 8, (spi_cpol_t)(TFT_SPI_MODE >> 1), (spi_cpha_t)(TFT_SPI_MODE & 0x1), SPI_MSB_FIRST)
#define SET_BUS_READ_MODE // spi_set_format(SPI_X, 8, (spi_cpol_t)0, (spi_cpha_t)0, SPI_MSB_FIRST)
#else
// Processor specific code used by SPI bus transaction begin/end_tft_write functions
#define SET_BUS_WRITE_MODE
#define SET_BUS_READ_MODE
#endif
// Code to check if SPI or DMA is busy, used by SPI bus transaction startWrite and/or endWrite functions
#if !defined(SPI_18BIT_DRIVER)
#define RP2040_DMA
// Code to check if DMA is busy, used by SPI DMA + transaction + endWrite functions
#define DMA_BUSY_CHECK dmaWait()
#else
#define DMA_BUSY_CHECK
#endif
// Handle high performance MHS RPi display type
#if defined (MHS_DISPLAY_TYPE) && !defined (RPI_DISPLAY_TYPE)
#define RPI_DISPLAY_TYPE
#endif
#if !defined (RP2040_PIO_INTERFACE) // SPI
#if defined (MHS_DISPLAY_TYPE) // High speed RPi TFT type always needs 16 bit transfers
// This swaps to 16 bit mode, used for commands so wait avoids clash with DC timing
#define INIT_TFT_DATA_BUS hw_write_masked(&spi_get_hw(SPI_X)->cr0, (16 - 1) << SPI_SSPCR0_DSS_LSB, SPI_SSPCR0_DSS_BITS)
#else
// Initialise processor specific SPI functions, used by init()
#define INIT_TFT_DATA_BUS // Not used
#endif
// Wait for tx to end, flush rx FIFO, clear rx overrun
#define SPI_BUSY_CHECK while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
while (spi_is_readable(SPI_X)) (void)spi_get_hw(SPI_X)->dr; \
spi_get_hw(SPI_X)->icr = SPI_SSPICR_RORIC_BITS
// To be safe, SUPPORT_TRANSACTIONS is assumed mandatory
#if !defined (SUPPORT_TRANSACTIONS)
#define SUPPORT_TRANSACTIONS
#endif
#else
// Different controllers have different minimum write cycle periods, so the PIO clock is changed accordingly
// The PIO clock is a division of the CPU clock so scales when the processor is overclocked
// PIO write frequency = (CPU clock/(4 * RP2040_PIO_CLK_DIV))
// The write cycle periods below assume a 125MHz CPU clock speed
#if defined (TFT_PARALLEL_8_BIT) || defined (TFT_PARALLEL_16_BIT)
#if defined (RP2040_PIO_CLK_DIV)
#if (RP2040_PIO_CLK_DIV > 0)
#define DIV_UNITS RP2040_PIO_CLK_DIV
#define DIV_FRACT 0
#else
#define DIV_UNITS 3
#define DIV_FRACT 0
#endif
#elif defined (TFT_PARALLEL_16_BIT)
// Different display drivers have different minimum write cycle times
#if defined (HX8357C_DRIVER) || defined (SSD1963_DRIVER)
#define DIV_UNITS 1 // 32ns write cycle time SSD1963, HX8357C (maybe HX8357D?)
#elif defined (ILI9486_DRIVER) || defined (HX8357B_DRIVER) || defined (HX8357D_DRIVER)
#define DIV_UNITS 2 // 64ns write cycle time ILI9486, HX8357D, HX8357B
#else // ILI9481 needs a slower cycle time
#define DIV_UNITS 3 // 96ns write cycle time
#endif
#define DIV_FRACT 0
#else // 8 bit parallel mode default 64ns write cycle time
#define DIV_UNITS 2
#define DIV_FRACT 0 // Note: Fractional values done with clock period dithering
#endif
#endif
// Initialise TFT data bus
#if defined (TFT_PARALLEL_8_BIT) || defined (TFT_PARALLEL_16_BIT)
#define INIT_TFT_DATA_BUS pioinit(DIV_UNITS, DIV_FRACT);
#elif defined (RP2040_PIO_SPI)
#define INIT_TFT_DATA_BUS pioinit(SPI_FREQUENCY);
#endif
#define SPI_BUSY_CHECK
// Set the state machine clock divider (from integer and fractional parts - 16:8)
#define PARALLEL_INIT_TFT_DATA_BUS // Not used
#endif
// If smooth fonts are enabled the filing system may need to be loaded
#if defined (SMOOTH_FONT) && !defined (ARDUINO_ARCH_MBED)
// Call up the filing system for the anti-aliased fonts
//#define FS_NO_GLOBALS
#include <FS.h>
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Define the DC (TFT Data/Command or Register Select (RS))pin drive code
////////////////////////////////////////////////////////////////////////////////////////
#ifndef TFT_DC
#define DC_C // No macro allocated so it generates no code
#define DC_D // No macro allocated so it generates no code
#else
#if !defined (RP2040_PIO_INTERFACE)// SPI
//#define DC_C sio_hw->gpio_clr = (1ul << TFT_DC)
//#define DC_D sio_hw->gpio_set = (1ul << TFT_DC)
#if defined (RPI_DISPLAY_TYPE) && !defined (MHS_DISPLAY_TYPE)
#define DC_C digitalWrite(TFT_DC, LOW);
#define DC_D digitalWrite(TFT_DC, HIGH);
#else
#define DC_C sio_hw->gpio_clr = (1ul << TFT_DC)
#define DC_D sio_hw->gpio_set = (1ul << TFT_DC)
#endif
#else
// PIO takes control of TFT_DC
// Must wait for data to flush through before changing DC line
#define DC_C WAIT_FOR_STALL; \
tft_pio->sm[pio_sm].instr = pio_instr_clr_dc
// Flush has happened before this and mode changed back to 16 bit
#define DC_D tft_pio->sm[pio_sm].instr = pio_instr_set_dc
#endif
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Define the CS (TFT chip select) pin drive code
////////////////////////////////////////////////////////////////////////////////////////
#ifndef TFT_CS
#define CS_L // No macro allocated so it generates no code
#define CS_H // No macro allocated so it generates no code
#else
#if !defined (RP2040_PIO_INTERFACE) // SPI
#if defined (RPI_DISPLAY_TYPE) && !defined (MHS_DISPLAY_TYPE)
#define CS_L digitalWrite(TFT_CS, LOW);
#define CS_H digitalWrite(TFT_CS, HIGH);
#else
#define CS_L sio_hw->gpio_clr = (1ul << TFT_CS)
#define CS_H sio_hw->gpio_set = (1ul << TFT_CS)
#endif
#else // PIO interface display
#define CS_L sio_hw->gpio_clr = (1ul << TFT_CS)
#define CS_H WAIT_FOR_STALL; sio_hw->gpio_set = (1ul << TFT_CS)
#endif
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Make sure TFT_RD is defined if not used to avoid an error message
////////////////////////////////////////////////////////////////////////////////////////
// At the moment read is not supported for parallel mode, tie TFT signal high
#ifdef TFT_RD
#if (TFT_RD >= 0)
#define RD_L sio_hw->gpio_clr = (1ul << TFT_RD)
//#define RD_L digitalWrite(TFT_WR, LOW)
#define RD_H sio_hw->gpio_set = (1ul << TFT_RD)
//#define RD_H digitalWrite(TFT_WR, HIGH)
#else
#define RD_L
#define RD_H
#endif
#else
#define TFT_RD -1
#define RD_L
#define RD_H
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Define the WR (TFT Write) pin drive code
////////////////////////////////////////////////////////////////////////////////////////
#if !defined (TFT_PARALLEL_8_BIT) && !defined (TFT_PARALLEL_16_BIT) // SPI
#ifdef TFT_WR
#define WR_L digitalWrite(TFT_WR, LOW)
#define WR_H digitalWrite(TFT_WR, HIGH)
#endif
#else
// The PIO manages the write line
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Define the touch screen chip select pin drive code
////////////////////////////////////////////////////////////////////////////////////////
#if !defined (RP2040_PIO_INTERFACE)// SPI
#if !defined TOUCH_CS || (TOUCH_CS < 0)
#define T_CS_L // No macro allocated so it generates no code
#define T_CS_H // No macro allocated so it generates no code
#else
#define T_CS_L digitalWrite(TOUCH_CS, LOW)
#define T_CS_H digitalWrite(TOUCH_CS, HIGH)
#endif
#else
#ifdef TOUCH_CS
#error Touch screen not supported in parallel or SPI PIO mode, use a separate library.
#endif
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Make sure TFT_MISO is defined if not used to avoid an error message
////////////////////////////////////////////////////////////////////////////////////////
#ifndef TFT_MISO
#define TFT_MISO -1
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Macros to write commands/pixel colour data to a SPI ILI948x TFT
////////////////////////////////////////////////////////////////////////////////////////
#if !defined (RP2040_PIO_INTERFACE) // SPI
#if defined (SPI_18BIT_DRIVER) // SPI 18 bit colour
// Write 8 bits to TFT
#define tft_Write_8(C) spi_get_hw(SPI_X)->dr = (uint32_t)(C); \
while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
//#define tft_Write_8(C) spi.transfer(C);
#define tft_Write_8N(B) while (!spi_is_writable(SPI_X)){}; \
spi_get_hw(SPI_X)->dr = (uint8_t)(B)
// Convert 16 bit colour to 18 bit and write in 3 bytes
#define tft_Write_16(C) tft_Write_8N(((C) & 0xF800)>>8); \
tft_Write_8N(((C) & 0x07E0)>>3); \
tft_Write_8N(((C) & 0x001F)<<3)
// Convert 16 bit colour to 18 bit and write in 3 bytes
#define tft_Write_16N(C) tft_Write_8N(((C) & 0xF800)>>8); \
tft_Write_8N(((C) & 0x07E0)>>3); \
tft_Write_8N(((C) & 0x001F)<<3)
// Convert swapped byte 16 bit colour to 18 bit and write in 3 bytes
#define tft_Write_16S(C) tft_Write_8N((C) & 0xF8); \
tft_Write_8N(((C) & 0xE000)>>11 | ((C) & 0x07)<<5); \
tft_Write_8N(((C) & 0x1F00)>>5)
// Write 32 bits to TFT
#define tft_Write_32(C) tft_Write_8N(C>>24); \
tft_Write_8N(C>>16); \
tft_Write_8N(C>>8); \
tft_Write_8N(C)
// Write two address coordinates
#define tft_Write_32C(C,D) tft_Write_8N(C>>8); \
tft_Write_8N(C); \
tft_Write_8N(D>>8); \
tft_Write_8N(D)
// Write same value twice
#define tft_Write_32D(C) tft_Write_8N(C>>8); \
tft_Write_8N(C); \
tft_Write_8N(C>>8); \
tft_Write_8N(C)
////////////////////////////////////////////////////////////////////////////////////////
// Macros to write commands/pixel colour data to other displays
////////////////////////////////////////////////////////////////////////////////////////
#else
#if defined (MHS_DISPLAY_TYPE) // High speed RPi TFT type always needs 16 bit transfers
// This swaps to 16 bit mode, used for commands so wait avoids clash with DC timing
#define tft_Write_8(C) while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
hw_write_masked(&spi_get_hw(SPI_X)->cr0, (16 - 1) << SPI_SSPCR0_DSS_LSB, SPI_SSPCR0_DSS_BITS); \
spi_get_hw(SPI_X)->dr = (uint32_t)((C) | ((C)<<8)); \
while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
// Note: the following macros do not wait for the end of transmission
#define tft_Write_16(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_16N(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_16S(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)<<8 | (C)>>8
#define tft_Write_32(C) spi_get_hw(SPI_X)->dr = (uint32_t)((C)>>16); spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_32C(C,D) spi_get_hw(SPI_X)->dr = (uint32_t)(C); spi_get_hw(SPI_X)->dr = (uint32_t)(D)
#define tft_Write_32D(C) spi_get_hw(SPI_X)->dr = (uint32_t)(C); spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#elif defined (RPI_DISPLAY_TYPE) // RPi TFT type always needs 16 bit transfers
#define tft_Write_8(C) spi.transfer(C); spi.transfer(C)
#define tft_Write_16(C) spi.transfer((uint8_t)((C)>>8));spi.transfer((uint8_t)((C)>>0))
#define tft_Write_16N(C) spi.transfer((uint8_t)((C)>>8));spi.transfer((uint8_t)((C)>>0))
#define tft_Write_16S(C) spi.transfer((uint8_t)((C)>>0));spi.transfer((uint8_t)((C)>>8))
#define tft_Write_32(C) \
tft_Write_16((uint16_t) ((C)>>16)); \
tft_Write_16((uint16_t) ((C)>>0))
#define tft_Write_32C(C,D) \
spi.transfer(0); spi.transfer((C)>>8); \
spi.transfer(0); spi.transfer((C)>>0); \
spi.transfer(0); spi.transfer((D)>>8); \
spi.transfer(0); spi.transfer((D)>>0)
#define tft_Write_32D(C) \
spi.transfer(0); spi.transfer((C)>>8); \
spi.transfer(0); spi.transfer((C)>>0); \
spi.transfer(0); spi.transfer((C)>>8); \
spi.transfer(0); spi.transfer((C)>>0)
#elif defined (ILI9225_DRIVER) // Needs gaps between commands + data bytes, so use slower transfer functions
// Warning: these all end in 8 bit SPI mode!
#define tft_Write_8(C) spi.transfer(C);
#define tft_Write_16(C) spi.transfer16(C)
#define tft_Write_16N(C) spi.transfer16(C)
#define tft_Write_16S(C) spi.transfer16((C)<<8 | (C)>>8)
#define tft_Write_32(C) spi.transfer16((C)>>16); spi.transfer16(C)
#define tft_Write_32C(C,D) spi.transfer16(C); spi.transfer16(D)
#define tft_Write_32D(C) spi.transfer16(C); spi.transfer16(C)
#else
// This swaps to 8 bit mode, then back to 16 bit mode
#define tft_Write_8(C) while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
hw_write_masked(&spi_get_hw(SPI_X)->cr0, (8 - 1) << SPI_SSPCR0_DSS_LSB, SPI_SSPCR0_DSS_BITS); \
spi_get_hw(SPI_X)->dr = (uint32_t)(C); \
while (spi_get_hw(SPI_X)->sr & SPI_SSPSR_BSY_BITS) {}; \
hw_write_masked(&spi_get_hw(SPI_X)->cr0, (16 - 1) << SPI_SSPCR0_DSS_LSB, SPI_SSPCR0_DSS_BITS)
// Note: the following macros do not wait for the end of transmission
#define tft_Write_16(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_16N(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_16S(C) while (!spi_is_writable(SPI_X)){}; spi_get_hw(SPI_X)->dr = (uint32_t)(C)<<8 | (C)>>8
#define tft_Write_32(C) spi_get_hw(SPI_X)->dr = (uint32_t)((C)>>16); spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#define tft_Write_32C(C,D) spi_get_hw(SPI_X)->dr = (uint32_t)(C); spi_get_hw(SPI_X)->dr = (uint32_t)(D)
#define tft_Write_32D(C) spi_get_hw(SPI_X)->dr = (uint32_t)(C); spi_get_hw(SPI_X)->dr = (uint32_t)(C)
#endif // RPI_DISPLAY_TYPE
#endif
#else // Parallel 8 bit or PIO SPI
// Wait for the PIO to stall (SM pull request finds no data in TX FIFO)
// This is used to detect when the SM is idle and hence ready for a jump instruction
#define WAIT_FOR_STALL tft_pio->fdebug = pull_stall_mask; while (!(tft_pio->fdebug & pull_stall_mask))
// Wait until at least "S" locations free
#define WAIT_FOR_FIFO_FREE(S) while (((tft_pio->flevel >> (pio_sm * 8)) & 0x000F) > (8-S)){}
// Wait until at least 5 locations free
#define WAIT_FOR_FIFO_5_FREE while ((tft_pio->flevel) & (0x000c << (pio_sm * 8))){}
// Wait until at least 1 location free
#define WAIT_FOR_FIFO_1_FREE while ((tft_pio->flevel) & (0x0008 << (pio_sm * 8))){}
// Wait for FIFO to empty (use before swapping to 8 bits)
#define WAIT_FOR_FIFO_EMPTY while(!(tft_pio->fstat & (1u << (PIO_FSTAT_TXEMPTY_LSB + pio_sm))))
// The write register of the TX FIFO.
#define TX_FIFO tft_pio->txf[pio_sm]
// Temporary - to be deleted
#define GPIO_DIR_MASK 0
#if defined (SPI_18BIT_DRIVER) // SPI 18 bit colour
// This writes 8 bits, then switches back to 16 bit mode automatically
// Have already waited for pio stalled (last data write complete) when DC switched to command mode
// The wait for stall allows DC to be changed immediately afterwards
#define tft_Write_8(C) tft_pio->sm[pio_sm].instr = pio_instr_jmp8; \
TX_FIFO = (C); \
WAIT_FOR_STALL
// Used to send last byte for 32 bit macros below since PIO sends 24 bits
#define tft_Write_8L(C) WAIT_FOR_STALL; \
tft_pio->sm[pio_sm].instr = pio_instr_jmp8; \
TX_FIFO = (C)
// Note: the following macros do not wait for the end of transmission
#define tft_Write_16(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = ((((uint32_t)(C) & 0xF800)<<8) | (((C) & 0x07E0)<<5) | (((C) & 0x001F)<<3))
#define tft_Write_16N(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = ((((uint32_t)(C) & 0xF800)<<8) | (((C) & 0x07E0)<<5) | (((C) & 0x001F)<<3))
#define tft_Write_16S(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = ((((uint32_t)(C) & 0xF8) << 16) | (((C) & 0xE000)>>3) | (((C) & 0x07)<<13) | (((C) & 0x1F00)>>5))
#define tft_Write_32(C) WAIT_FOR_FIFO_FREE(2); TX_FIFO = ((C)>>8); WAIT_FOR_STALL; tft_Write_8(C)
#define tft_Write_32C(C,D) WAIT_FOR_FIFO_FREE(2); TX_FIFO = (((C)<<8) | ((D)>>8)); tft_Write_8L(D)
#define tft_Write_32D(C) WAIT_FOR_FIFO_FREE(2); TX_FIFO = (((C)<<8) | ((C)>>8)); tft_Write_8L(C)
#else // PIO interface, SPI or parallel
// This writes 8 bits, then switches back to 16 bit mode automatically
// Have already waited for pio stalled (last data write complete) when DC switched to command mode
// The wait for stall allows DC to be changed immediately afterwards
#if defined (TFT_PARALLEL_8_BIT) || defined (RP2040_PIO_SPI)
#define tft_Write_8(C) tft_pio->sm[pio_sm].instr = pio_instr_jmp8; \
TX_FIFO = (C); \
WAIT_FOR_STALL
#else // For 16 bit parallel 16 bits are always sent
#define tft_Write_8(C) TX_FIFO = (C); \
WAIT_FOR_STALL
#endif
// Note: the following macros do not wait for the end of transmission
#define tft_Write_16(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = (C)
#define tft_Write_16N(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = (C)
#define tft_Write_16S(C) WAIT_FOR_FIFO_FREE(1); TX_FIFO = ((C)<<8) | ((C)>>8)
#define tft_Write_32(C) WAIT_FOR_FIFO_FREE(2); TX_FIFO = ((C)>>16); TX_FIFO = (C)
#define tft_Write_32C(C,D) WAIT_FOR_FIFO_FREE(2); TX_FIFO = (C); TX_FIFO = (D)
#define tft_Write_32D(C) WAIT_FOR_FIFO_FREE(2); TX_FIFO = (C); TX_FIFO = (C)
#endif
#endif
#ifndef tft_Write_16N
#define tft_Write_16N tft_Write_16
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Macros to read from display using SPI or software SPI
////////////////////////////////////////////////////////////////////////////////////////
#if !defined (RP2040_PIO_INTERFACE)// SPI
#if defined (TFT_SDA_READ)
// Use a bit banged function call for STM32 and bi-directional SDA pin
#define TFT_eSPI_ENABLE_8_BIT_READ // Enable tft_Read_8(void);
#define SCLK_L digitalWrite(TFT_SCLK, LOW)
#define SCLK_H digitalWrite(TFT_SCLK, LOW)
#else
// Use a SPI read transfer
#define tft_Read_8() spi.transfer(0)
#endif
#endif
////////////////////////////////////////////////////////////////////////////////////////
// Temporary to keep the "Arduino Mbed OS RP2040 Boards" support package happy
////////////////////////////////////////////////////////////////////////////////////////
#if defined(ARDUINO_ARCH_RP2040)
#define ltoa itoa
#endif
#endif // Header end
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