From 17ee1a877d2d8d3f1b47d917ceb4cb1b6dec792c Mon Sep 17 00:00:00 2001 From: Martino Facchin Date: Mon, 24 May 2021 23:32:56 +0200 Subject: [PATCH] Add support for Arduino Nano RP2040 Connect (#425) * Add support for Arduino Nano RP2040 Connect * Add support for at25sf128a flash Derived from W25Q080 code, QE bit is set via a single command --- .../boards/arduino_nano_rp2040_connect.h | 88 ++++++ src/rp2_common/boot_stage2/boot2_at25sf128a.S | 285 ++++++++++++++++++ .../boot_stage2/include/boot_stage2/config.h | 12 + 3 files changed, 385 insertions(+) create mode 100644 src/boards/include/boards/arduino_nano_rp2040_connect.h create mode 100644 src/rp2_common/boot_stage2/boot2_at25sf128a.S diff --git a/src/boards/include/boards/arduino_nano_rp2040_connect.h b/src/boards/include/boards/arduino_nano_rp2040_connect.h new file mode 100644 index 0000000..9725cb7 --- /dev/null +++ b/src/boards/include/boards/arduino_nano_rp2040_connect.h @@ -0,0 +1,88 @@ +/* + * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +// ----------------------------------------------------- +// NOTE: THIS HEADER IS ALSO INCLUDED BY ASSEMBLER SO +// SHOULD ONLY CONSIST OF PREPROCESSOR DIRECTIVES +// ----------------------------------------------------- + +#ifndef _BOARDS_ARDUINO_NANO_RP2040_CONNECT_H +#define _BOARDS_ARDUINO_NANO_RP2040_CONNECT_H + +// For board detection +#define ARDUINO_NANO_RP2040_CONNECT + +//------------- UART -------------// +#ifndef PICO_DEFAULT_UART +#define PICO_DEFAULT_UART 0 +#endif + +#ifndef PICO_DEFAULT_UART_TX_PIN +#define PICO_DEFAULT_UART_TX_PIN 0 +#endif + +#ifndef PICO_DEFAULT_UART_RX_PIN +#define PICO_DEFAULT_UART_RX_PIN 1 +#endif + +//------------- LED -------------// +#ifndef PICO_DEFAULT_LED_PIN +#define PICO_DEFAULT_LED_PIN 6 +#endif +// no PICO_DEFAULT_WS2812_PIN + +//------------- I2C -------------// +#ifndef PICO_DEFAULT_I2C +#define PICO_DEFAULT_I2C 0 +#endif + +#ifndef PICO_DEFAULT_I2C_SDA_PIN +#define PICO_DEFAULT_I2C_SDA_PIN 12 +#endif + +#ifndef PICO_DEFAULT_I2C_SCL_PIN +#define PICO_DEFAULT_I2C_SCL_PIN 13 +#endif + +//------------- SPI -------------// +#ifndef PICO_DEFAULT_SPI +#define PICO_DEFAULT_SPI 0 +#endif + +#ifndef PICO_DEFAULT_SPI_TX_PIN +#define PICO_DEFAULT_SPI_TX_PIN 7 +#endif + +#ifndef PICO_DEFAULT_SPI_RX_PIN +#define PICO_DEFAULT_SPI_RX_PIN 4 +#endif + +#ifndef PICO_DEFAULT_SPI_SCK_PIN +#define PICO_DEFAULT_SPI_SCK_PIN 6 +#endif + +//------------- FLASH -------------// + +#define PICO_BOOT_STAGE2_CHOOSE_AT25SF128A 1 + +#ifndef PICO_FLASH_SPI_CLKDIV +#define PICO_FLASH_SPI_CLKDIV 2 +#endif + +#ifndef PICO_FLASH_SIZE_BYTES +#define PICO_FLASH_SIZE_BYTES (16 * 1024 * 1024) +#endif + +// All boards have B1 RP2040 +#ifndef PICO_FLOAT_SUPPORT_ROM_V1 +#define PICO_FLOAT_SUPPORT_ROM_V1 0 +#endif + +#ifndef PICO_DOUBLE_SUPPORT_ROM_V1 +#define PICO_DOUBLE_SUPPORT_ROM_V1 0 +#endif + +#endif diff --git a/src/rp2_common/boot_stage2/boot2_at25sf128a.S b/src/rp2_common/boot_stage2/boot2_at25sf128a.S new file mode 100644 index 0000000..be232ff --- /dev/null +++ b/src/rp2_common/boot_stage2/boot2_at25sf128a.S @@ -0,0 +1,285 @@ +// ---------------------------------------------------------------------------- +// Second stage boot code +// Copyright (c) 2019-2021 Raspberry Pi (Trading) Ltd. +// SPDX-License-Identifier: BSD-3-Clause +// +// Device: Adesto AT25SF128A +// Based on W25Q080 code: main difference is the QE bit is being set +// via command 0x31 +// +// Description: Configures AT25SF128A to run in Quad I/O continuous read XIP mode +// +// Details: * Check status register 2 to determine if QSPI mode is enabled, +// and perform an SR2 programming cycle if necessary. +// * Use SSI to perform a dummy 0xEB read command, with the mode +// continuation bits set, so that the flash will not require +// 0xEB instruction prefix on subsequent reads. +// * Configure SSI to write address, mode bits, but no instruction. +// SSI + flash are now jointly in a state where continuous reads +// can take place. +// * Jump to exit pointer passed in via lr. Bootrom passes null, +// in which case this code uses a default 256 byte flash offset +// +// Building: * This code must be position-independent, and use stack only +// * The code will be padded to a size of 256 bytes, including a +// 4-byte checksum. Therefore code size cannot exceed 252 bytes. +// ---------------------------------------------------------------------------- + +#include "pico/asm_helper.S" +#include "hardware/regs/addressmap.h" +#include "hardware/regs/ssi.h" +#include "hardware/regs/pads_qspi.h" + +// ---------------------------------------------------------------------------- +// Config section +// ---------------------------------------------------------------------------- +// It should be possible to support most flash devices by modifying this section + +// The serial flash interface will run at clk_sys/PICO_FLASH_SPI_CLKDIV. +// This must be a positive, even integer. +// The bootrom is very conservative with SPI frequency, but here we should be +// as aggressive as possible. + +#ifndef PICO_FLASH_SPI_CLKDIV +#define PICO_FLASH_SPI_CLKDIV 4 +#endif +#if PICO_FLASH_SPI_CLKDIV & 1 +#error PICO_FLASH_SPI_CLKDIV must be even +#endif + +// Define interface width: single/dual/quad IO +#define FRAME_FORMAT SSI_CTRLR0_SPI_FRF_VALUE_QUAD + +// For W25Q080 this is the "Read data fast quad IO" instruction: +#define CMD_READ 0xeb + +// "Mode bits" are 8 special bits sent immediately after +// the address bits in a "Read Data Fast Quad I/O" command sequence. +// On W25Q080, the four LSBs are don't care, and if MSBs == 0xa, the +// next read does not require the 0xeb instruction prefix. +#define MODE_CONTINUOUS_READ 0x20 + +// The number of address + mode bits, divided by 4 (always 4, not function of +// interface width). +#define ADDR_L 8 + +// How many clocks of Hi-Z following the mode bits. For W25Q080, 4 dummy cycles +// are required. +#define WAIT_CYCLES 4 + +// If defined, we will read status reg, compare to SREG_DATA, and overwrite +// with our value if the SR doesn't match. +// We do a two-byte write to SR1 (01h cmd) rather than a one-byte write to +// SR2 (31h cmd) as the latter command isn't supported by WX25Q080. +// This isn't great because it will remove block protections. +// A better solution is to use a volatile SR write if your device supports it. +#define PROGRAM_STATUS_REG + +#define CMD_WRITE_ENABLE 0x06 +#define CMD_READ_STATUS 0x05 +#define CMD_READ_STATUS2 0x35 +#define CMD_WRITE_STATUS 0x01 +#define CMD_WRITE_STATUS2 0x31 +#define SREG_DATA 0x02 // Enable quad-SPI mode + +// ---------------------------------------------------------------------------- +// Start of 2nd Stage Boot Code +// ---------------------------------------------------------------------------- + +.syntax unified +.cpu cortex-m0plus +.thumb + +.section .text + +// The exit point is passed in lr. If entered from bootrom, this will be the +// flash address immediately following this second stage (0x10000100). +// Otherwise it will be a return address -- second stage being called as a +// function by user code, after copying out of XIP region. r3 holds SSI base, +// r0...2 used as temporaries. Other GPRs not used. +.global _stage2_boot +.type _stage2_boot,%function +.thumb_func +_stage2_boot: + push {lr} + + // Set pad configuration: + // - SCLK 8mA drive, no slew limiting + // - SDx disable input Schmitt to reduce delay + + ldr r3, =PADS_QSPI_BASE + movs r0, #(2 << PADS_QSPI_GPIO_QSPI_SCLK_DRIVE_LSB | PADS_QSPI_GPIO_QSPI_SCLK_SLEWFAST_BITS) + str r0, [r3, #PADS_QSPI_GPIO_QSPI_SCLK_OFFSET] + ldr r0, [r3, #PADS_QSPI_GPIO_QSPI_SD0_OFFSET] + movs r1, #PADS_QSPI_GPIO_QSPI_SD0_SCHMITT_BITS + bics r0, r1 + str r0, [r3, #PADS_QSPI_GPIO_QSPI_SD0_OFFSET] + str r0, [r3, #PADS_QSPI_GPIO_QSPI_SD1_OFFSET] + str r0, [r3, #PADS_QSPI_GPIO_QSPI_SD2_OFFSET] + str r0, [r3, #PADS_QSPI_GPIO_QSPI_SD3_OFFSET] + + ldr r3, =XIP_SSI_BASE + + // Disable SSI to allow further config + movs r1, #0 + str r1, [r3, #SSI_SSIENR_OFFSET] + + // Set baud rate + movs r1, #PICO_FLASH_SPI_CLKDIV + str r1, [r3, #SSI_BAUDR_OFFSET] + + // Set 1-cycle sample delay. If PICO_FLASH_SPI_CLKDIV == 2 then this means, + // if the flash launches data on SCLK posedge, we capture it at the time that + // the next SCLK posedge is launched. This is shortly before that posedge + // arrives at the flash, so data hold time should be ok. For + // PICO_FLASH_SPI_CLKDIV > 2 this pretty much has no effect. + + movs r1, #1 + movs r2, #SSI_RX_SAMPLE_DLY_OFFSET // == 0xf0 so need 8 bits of offset significance + str r1, [r3, r2] + + +// On QSPI parts we usually need a 01h SR-write command to enable QSPI mode +// (i.e. turn WPn and HOLDn into IO2/IO3) +#ifdef PROGRAM_STATUS_REG +program_sregs: +#define CTRL0_SPI_TXRX \ + (7 << SSI_CTRLR0_DFS_32_LSB) | /* 8 bits per data frame */ \ + (SSI_CTRLR0_TMOD_VALUE_TX_AND_RX << SSI_CTRLR0_TMOD_LSB) + + ldr r1, =(CTRL0_SPI_TXRX) + str r1, [r3, #SSI_CTRLR0_OFFSET] + + // Enable SSI and select slave 0 + movs r1, #1 + str r1, [r3, #SSI_SSIENR_OFFSET] + + // Check whether SR needs updating + movs r0, #CMD_READ_STATUS2 + bl read_flash_sreg + movs r2, #SREG_DATA + cmp r0, r2 + beq skip_sreg_programming + + // Send write enable command + movs r1, #CMD_WRITE_ENABLE + str r1, [r3, #SSI_DR0_OFFSET] + + // Poll for completion and discard RX + bl wait_ssi_ready + ldr r1, [r3, #SSI_DR0_OFFSET] + + // Send status write command followed by data bytes + movs r1, #CMD_WRITE_STATUS2 + str r1, [r3, #SSI_DR0_OFFSET] + str r2, [r3, #SSI_DR0_OFFSET] + + bl wait_ssi_ready + ldr r1, [r3, #SSI_DR0_OFFSET] + ldr r1, [r3, #SSI_DR0_OFFSET] + ldr r1, [r3, #SSI_DR0_OFFSET] + + // Poll status register for write completion +1: + movs r0, #CMD_READ_STATUS + bl read_flash_sreg + movs r1, #1 + tst r0, r1 + bne 1b + +skip_sreg_programming: + + // Disable SSI again so that it can be reconfigured + movs r1, #0 + str r1, [r3, #SSI_SSIENR_OFFSET] +#endif + +// Currently the flash expects an 8 bit serial command prefix on every +// transfer, which is a waste of cycles. Perform a dummy Fast Read Quad I/O +// command, with mode bits set such that the flash will not expect a serial +// command prefix on *subsequent* transfers. We don't care about the results +// of the read, the important part is the mode bits. + +dummy_read: +#define CTRLR0_ENTER_XIP \ + (FRAME_FORMAT /* Quad I/O mode */ \ + << SSI_CTRLR0_SPI_FRF_LSB) | \ + (31 << SSI_CTRLR0_DFS_32_LSB) | /* 32 data bits */ \ + (SSI_CTRLR0_TMOD_VALUE_EEPROM_READ /* Send INST/ADDR, Receive Data */ \ + << SSI_CTRLR0_TMOD_LSB) + + ldr r1, =(CTRLR0_ENTER_XIP) + str r1, [r3, #SSI_CTRLR0_OFFSET] + + movs r1, #0x0 // NDF=0 (single 32b read) + str r1, [r3, #SSI_CTRLR1_OFFSET] + +#define SPI_CTRLR0_ENTER_XIP \ + (ADDR_L << SSI_SPI_CTRLR0_ADDR_L_LSB) | /* Address + mode bits */ \ + (WAIT_CYCLES << SSI_SPI_CTRLR0_WAIT_CYCLES_LSB) | /* Hi-Z dummy clocks following address + mode */ \ + (SSI_SPI_CTRLR0_INST_L_VALUE_8B \ + << SSI_SPI_CTRLR0_INST_L_LSB) | /* 8-bit instruction */ \ + (SSI_SPI_CTRLR0_TRANS_TYPE_VALUE_1C2A /* Send Command in serial mode then address in Quad I/O mode */ \ + << SSI_SPI_CTRLR0_TRANS_TYPE_LSB) + + ldr r1, =(SPI_CTRLR0_ENTER_XIP) + ldr r0, =(XIP_SSI_BASE + SSI_SPI_CTRLR0_OFFSET) // SPI_CTRL0 Register + str r1, [r0] + + movs r1, #1 // Re-enable SSI + str r1, [r3, #SSI_SSIENR_OFFSET] + + movs r1, #CMD_READ + str r1, [r3, #SSI_DR0_OFFSET] // Push SPI command into TX FIFO + movs r1, #MODE_CONTINUOUS_READ // 32-bit: 24 address bits (we don't care, so 0) and M[7:4]=1010 + str r1, [r3, #SSI_DR0_OFFSET] // Push Address into TX FIFO - this will trigger the transaction + + // Poll for completion + bl wait_ssi_ready + +// The flash is in a state where we can blast addresses in parallel, and get +// parallel data back. Now configure the SSI to translate XIP bus accesses +// into QSPI transfers of this form. + + movs r1, #0 + str r1, [r3, #SSI_SSIENR_OFFSET] // Disable SSI (and clear FIFO) to allow further config + +// Note that the INST_L field is used to select what XIP data gets pushed into +// the TX FIFO: +// INST_L_0_BITS {ADDR[23:0],XIP_CMD[7:0]} Load "mode bits" into XIP_CMD +// Anything else {XIP_CMD[7:0],ADDR[23:0]} Load SPI command into XIP_CMD +configure_ssi: +#define SPI_CTRLR0_XIP \ + (MODE_CONTINUOUS_READ /* Mode bits to keep flash in continuous read mode */ \ + << SSI_SPI_CTRLR0_XIP_CMD_LSB) | \ + (ADDR_L << SSI_SPI_CTRLR0_ADDR_L_LSB) | /* Total number of address + mode bits */ \ + (WAIT_CYCLES << SSI_SPI_CTRLR0_WAIT_CYCLES_LSB) | /* Hi-Z dummy clocks following address + mode */ \ + (SSI_SPI_CTRLR0_INST_L_VALUE_NONE /* Do not send a command, instead send XIP_CMD as mode bits after address */ \ + << SSI_SPI_CTRLR0_INST_L_LSB) | \ + (SSI_SPI_CTRLR0_TRANS_TYPE_VALUE_2C2A /* Send Address in Quad I/O mode (and Command but that is zero bits long) */ \ + << SSI_SPI_CTRLR0_TRANS_TYPE_LSB) + + ldr r1, =(SPI_CTRLR0_XIP) + ldr r0, =(XIP_SSI_BASE + SSI_SPI_CTRLR0_OFFSET) + str r1, [r0] + + movs r1, #1 + str r1, [r3, #SSI_SSIENR_OFFSET] // Re-enable SSI + +// Bus accesses to the XIP window will now be transparently serviced by the +// external flash on cache miss. We are ready to run code from flash. + +// Pull in standard exit routine +#include "boot2_helpers/exit_from_boot2.S" + +// Common functions +#include "boot2_helpers/wait_ssi_ready.S" +#ifdef PROGRAM_STATUS_REG +#include "boot2_helpers/read_flash_sreg.S" +#endif + +.global literals +literals: +.ltorg + +.end diff --git a/src/rp2_common/boot_stage2/include/boot_stage2/config.h b/src/rp2_common/boot_stage2/include/boot_stage2/config.h index a8179b9..5e57f95 100644 --- a/src/rp2_common/boot_stage2/include/boot_stage2/config.h +++ b/src/rp2_common/boot_stage2/include/boot_stage2/config.h @@ -44,6 +44,16 @@ #endif #define _BOOT_STAGE2_SELECTED #endif +// PICO_CONFIG: PICO_BOOT_STAGE2_CHOOSE_AT25SF128A, Select boot2_at25sf128a as the boot stage 2 when no boot stage 2 selection is made by the CMake build, type=bool, default=0, group=boot_stage2 +#ifndef PICO_BOOT_STAGE2_CHOOSE_AT25SF128A + #define PICO_BOOT_STAGE2_CHOOSE_AT25SF128A 0 +#elif PICO_BOOT_STAGE2_CHOOSE_AT25SF128A + #ifdef _BOOT_STAGE2_SELECTED + #error multiple boot stage 2 options chosen + #endif + #define _BOOT_STAGE2_SELECTED +#endif + // PICO_CONFIG: PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H, Select boot2_generic_03h as the boot stage 2 when no boot stage 2 selection is made by the CMake build, type=bool, default=1, group=boot_stage2 #if defined(PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H) && PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H #ifdef _BOOT_STAGE2_SELECTED @@ -65,6 +75,8 @@ #define _BOOT_STAGE2 boot2_w25q080 #elif PICO_BOOT_STAGE2_CHOOSE_W25X10CL #define _BOOT_STAGE2 boot2_w25x10cl + #elif PICO_BOOT_STAGE2_CHOOSE_AT25SF128A + #define _BOOT_STAGE2 boot2_at25sf128a #elif !defined(PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H) || PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H #undef PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H #define PICO_BOOT_STAGE2_CHOOSE_GENERIC_03H 1