From 5846b40f7444af96b0d8ddf3af9b558193c2475d Mon Sep 17 00:00:00 2001 From: Nick Brassel Date: Sat, 2 Jul 2022 15:18:50 +1000 Subject: RP2040 emulated EEPROM. (#17519) --- .../wear_leveling/wear_leveling_rp2040_flash.c | 221 +++++++++++++++++++++ 1 file changed, 221 insertions(+) create mode 100644 platforms/chibios/drivers/wear_leveling/wear_leveling_rp2040_flash.c (limited to 'platforms/chibios/drivers/wear_leveling/wear_leveling_rp2040_flash.c') diff --git a/platforms/chibios/drivers/wear_leveling/wear_leveling_rp2040_flash.c b/platforms/chibios/drivers/wear_leveling/wear_leveling_rp2040_flash.c new file mode 100644 index 0000000000..640628e1e9 --- /dev/null +++ b/platforms/chibios/drivers/wear_leveling/wear_leveling_rp2040_flash.c @@ -0,0 +1,221 @@ +/** + * Copyright (c) 2020 Raspberry Pi (Trading) Ltd. + * Copyright (c) 2022 Nick Brassel (@tzarc) + * Copyright (c) 2022 Stefan Kerkmann (@KarlK90) + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include "pico/bootrom.h" +#include "hardware/flash.h" +#include "hardware/sync.h" +#include "hardware/structs/ssi.h" +#include "hardware/structs/ioqspi.h" + +#include +#include "timer.h" +#include "wear_leveling.h" +#include "wear_leveling_internal.h" + +#ifndef WEAR_LEVELING_RP2040_FLASH_BULK_COUNT +# define WEAR_LEVELING_RP2040_FLASH_BULK_COUNT 64 +#endif // WEAR_LEVELING_RP2040_FLASH_BULK_COUNT + +#define FLASHCMD_PAGE_PROGRAM 0x02 +#define FLASHCMD_READ_STATUS 0x05 +#define FLASHCMD_WRITE_ENABLE 0x06 + +extern uint8_t BOOT2_ROM[256]; +static uint32_t BOOT2_ROM_RAM[64]; + +static ssi_hw_t *const ssi = (ssi_hw_t *)XIP_SSI_BASE; + +// Sanity check +check_hw_layout(ssi_hw_t, ssienr, SSI_SSIENR_OFFSET); +check_hw_layout(ssi_hw_t, spi_ctrlr0, SSI_SPI_CTRLR0_OFFSET); + +static void __no_inline_not_in_flash_func(flash_enable_xip_via_boot2)(void) { + ((void (*)(void))BOOT2_ROM_RAM + 1)(); +} + +// Bitbanging the chip select using IO overrides, in case RAM-resident IRQs +// are still running, and the FIFO bottoms out. (the bootrom does the same) +static void __no_inline_not_in_flash_func(flash_cs_force)(bool high) { + uint32_t field_val = high ? IO_QSPI_GPIO_QSPI_SS_CTRL_OUTOVER_VALUE_HIGH : IO_QSPI_GPIO_QSPI_SS_CTRL_OUTOVER_VALUE_LOW; + hw_write_masked(&ioqspi_hw->io[1].ctrl, field_val << IO_QSPI_GPIO_QSPI_SS_CTRL_OUTOVER_LSB, IO_QSPI_GPIO_QSPI_SS_CTRL_OUTOVER_BITS); +} + +// Also allow any unbounded loops to check whether the above abort condition +// was asserted, and terminate early +static int __no_inline_not_in_flash_func(flash_was_aborted)(void) { + return *(io_rw_32 *)(IO_QSPI_BASE + IO_QSPI_GPIO_QSPI_SD1_CTRL_OFFSET) & IO_QSPI_GPIO_QSPI_SD1_CTRL_INOVER_BITS; +} + +// Put bytes from one buffer, and get bytes into another buffer. +// These can be the same buffer. +// If tx is NULL then send zeroes. +// If rx is NULL then all read data will be dropped. +// +// If rx_skip is nonzero, this many bytes will first be consumed from the FIFO, +// before reading a further count bytes into *rx. +// E.g. if you have written a command+address just before calling this function. +static void __no_inline_not_in_flash_func(flash_put_get)(const uint8_t *tx, uint8_t *rx, size_t count, size_t rx_skip) { + // Make sure there is never more data in flight than the depth of the RX + // FIFO. Otherwise, when we are interrupted for long periods, hardware + // will overflow the RX FIFO. + const uint max_in_flight = 16 - 2; // account for data internal to SSI + size_t tx_count = count; + size_t rx_count = count; + while (tx_count || rx_skip || rx_count) { + // NB order of reads, for pessimism rather than optimism + uint32_t tx_level = ssi_hw->txflr; + uint32_t rx_level = ssi_hw->rxflr; + bool did_something = false; // Expect this to be folded into control flow, not register + if (tx_count && tx_level + rx_level < max_in_flight) { + ssi->dr0 = (uint32_t)(tx ? *tx++ : 0); + --tx_count; + did_something = true; + } + if (rx_level) { + uint8_t rxbyte = ssi->dr0; + did_something = true; + if (rx_skip) { + --rx_skip; + } else { + if (rx) *rx++ = rxbyte; + --rx_count; + } + } + // APB load costs 4 cycles, so only do it on idle loops (our budget is + // 48 cyc/byte) + if (!did_something && __builtin_expect(flash_was_aborted(), 0)) break; + } + flash_cs_force(1); +} + +// Convenience wrapper for above +// (And it's hard for the debug host to get the tight timing between +// cmd DR0 write and the remaining data) +static void __no_inline_not_in_flash_func(_flash_do_cmd)(uint8_t cmd, const uint8_t *tx, uint8_t *rx, size_t count) { + flash_cs_force(0); + ssi->dr0 = cmd; + flash_put_get(tx, rx, count, 1); +} + +// Timing of this one is critical, so do not expose the symbol to debugger etc +static void __no_inline_not_in_flash_func(flash_put_cmd_addr)(uint8_t cmd, uint32_t addr) { + flash_cs_force(0); + addr |= cmd << 24; + for (int i = 0; i < 4; ++i) { + ssi->dr0 = addr >> 24; + addr <<= 8; + } +} + +// Poll the flash status register until the busy bit (LSB) clears +static void __no_inline_not_in_flash_func(flash_wait_ready)(void) { + uint8_t stat; + do { + _flash_do_cmd(FLASHCMD_READ_STATUS, NULL, &stat, 1); + } while (stat & 0x1 && !flash_was_aborted()); +} + +// Set the WEL bit (needed before any program/erase operation) +static void __no_inline_not_in_flash_func(flash_enable_write)(void) { + _flash_do_cmd(FLASHCMD_WRITE_ENABLE, NULL, NULL, 0); +} + +static void __no_inline_not_in_flash_func(pico_program_bulk)(uint32_t flash_address, backing_store_int_t *values, size_t item_count) { + rom_connect_internal_flash_fn connect_internal_flash = (rom_connect_internal_flash_fn)rom_func_lookup_inline(ROM_FUNC_CONNECT_INTERNAL_FLASH); + rom_flash_exit_xip_fn flash_exit_xip = (rom_flash_exit_xip_fn)rom_func_lookup_inline(ROM_FUNC_FLASH_EXIT_XIP); + rom_flash_flush_cache_fn flash_flush_cache = (rom_flash_flush_cache_fn)rom_func_lookup_inline(ROM_FUNC_FLASH_FLUSH_CACHE); + assert(connect_internal_flash && flash_exit_xip && flash_flush_cache); + + static backing_store_int_t bulk_write_buffer[WEAR_LEVELING_RP2040_FLASH_BULK_COUNT]; + + while (item_count) { + size_t batch_size = MIN(item_count, WEAR_LEVELING_RP2040_FLASH_BULK_COUNT); + for (size_t i = 0; i < batch_size; i++, values++, item_count--) { + bulk_write_buffer[i] = ~(*values); + } + __compiler_memory_barrier(); + + connect_internal_flash(); + flash_exit_xip(); + flash_enable_write(); + + flash_put_cmd_addr(FLASHCMD_PAGE_PROGRAM, flash_address); + flash_put_get((uint8_t *)bulk_write_buffer, NULL, batch_size * sizeof(backing_store_int_t), 4); + flash_wait_ready(); + flash_address += batch_size * sizeof(backing_store_int_t); + + flash_flush_cache(); + flash_enable_xip_via_boot2(); + } +} + +//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +// QMK Wear-Leveling Backing Store implementation + +static int interrupts; + +bool backing_store_init(void) { + bs_dprintf("Init\n"); + memcpy(BOOT2_ROM_RAM, BOOT2_ROM, sizeof(BOOT2_ROM)); + __compiler_memory_barrier(); + return true; +} + +bool backing_store_unlock(void) { + bs_dprintf("Unlock\n"); + return true; +} + +bool backing_store_erase(void) { +#ifdef WEAR_LEVELING_DEBUG_OUTPUT + uint32_t start = timer_read32(); +#endif + + // Ensure the backing size can be cleanly subtracted from the flash size without alignment issues. + _Static_assert((WEAR_LEVELING_BACKING_SIZE) % (FLASH_SECTOR_SIZE) == 0, "Backing size must be a multiple of FLASH_SECTOR_SIZE"); + + interrupts = save_and_disable_interrupts(); + flash_range_erase((WEAR_LEVELING_RP2040_FLASH_BASE), (WEAR_LEVELING_BACKING_SIZE)); + restore_interrupts(interrupts); + + bs_dprintf("Backing store erase took %ldms to complete\n", ((long)(timer_read32() - start))); + return true; +} + +bool backing_store_write(uint32_t address, backing_store_int_t value) { + return backing_store_write_bulk(address, &value, 1); +} + +bool backing_store_write_bulk(uint32_t address, backing_store_int_t *values, size_t item_count) { + uint32_t offset = (WEAR_LEVELING_RP2040_FLASH_BASE) + address; + bs_dprintf("Write "); + wl_dump(offset, values, sizeof(backing_store_int_t) * item_count); + interrupts = save_and_disable_interrupts(); + pico_program_bulk(offset, values, item_count); + restore_interrupts(interrupts); + return true; +} + +bool backing_store_lock(void) { + return true; +} + +bool backing_store_read(uint32_t address, backing_store_int_t *value) { + return backing_store_read_bulk(address, value, 1); +} + +bool backing_store_read_bulk(uint32_t address, backing_store_int_t *values, size_t item_count) { + uint32_t offset = (WEAR_LEVELING_RP2040_FLASH_BASE) + address; + backing_store_int_t *loc = (backing_store_int_t *)((XIP_BASE) + offset); + for (size_t i = 0; i < item_count; ++i) { + values[i] = ~loc[i]; + } + bs_dprintf("Read "); + wl_dump(offset, values, item_count * sizeof(backing_store_int_t)); + return true; +} -- cgit v1.2.3