From 9845a064ad22dd6cc6c720a8b765978a16e71ff7 Mon Sep 17 00:00:00 2001 From: Sean Cross Date: Thu, 2 Apr 2020 11:21:22 +0800 Subject: [PATCH] ports: fomu: move more functions into ram for stability The SPI flash on current Fomu firmware is slow. Circuitpython runs XIP from SPI flash, and so execution time can also be slow. Ordinarily this isn't a problem, however certain operations are time-sensitive. In particular, USB function needs to be handled quickly in order to prevent the host from re-enumerating the device. Place several critical TinyUSB structures into RAM, as well as several hot functions that are frequently called. This reduces execution time at the expense of system memory, and greatly improves system stability. Signed-off-by: Sean Cross --- ports/litex/boards/fomu/fomu-spi.ld | 40 ++++++++++++++++++++++++++--- 1 file changed, 37 insertions(+), 3 deletions(-) diff --git a/ports/litex/boards/fomu/fomu-spi.ld b/ports/litex/boards/fomu/fomu-spi.ld index 161ba607b..486c3cad1 100644 --- a/ports/litex/boards/fomu/fomu-spi.ld +++ b/ports/litex/boards/fomu/fomu-spi.ld @@ -26,8 +26,42 @@ SECTIONS . = ALIGN(4); _sdata = .; /* create a global symbol at data start; used by startup code in order to initialise the .data section in RAM */ - *(.itcm.*) /* Instruction Tightly Coupled Memory */ - *(.dtcm_data.*) /* Data Tightly Coupled Memory */ + *(.itcm.*) /* Instruction Tightly Coupled Memory */ + *(.dtcm_data.*) /* Data Tightly Coupled Memory */ + + *(.text.cmp_lfn) + *(.text.qstr_find_strn) + *(.text.dcd_edpt_xfer) + *(.text.pop_rule) + *(.text.ff_wtoupper) + *(.text.dir_find) + *(.text.push_rule) + *(.text.csr_writel) + *(.text.csr_readl) + *(.text.timer0_ev_pending_write) + *(.text.autoreload_tick) + *(.text.filesystem_tick) + *(.text.usb_background) + + *(.text.dcd_*) + *(.text.tud_control_*) + *(.text.tud_cdc_n_write_flush) + *(.text.tud_task) + *(.text.tu_edpt_dir) + *(.text.tu_fifo_empty) + *(.text.usbd_edpt_busy) + *(.text.irq_getmask) + *(.text.irq_setmask) + *(.text.irq_pending) + *(.text._osal_q_lock) + *(.text.osal_queue_receive) + + *(.text.mp_obj_get_type) + *(.text.mp_parse) + *(.text.parse_compile_execute) + *(.text.mp_map_lookup) + *(.text.mp_execute_bytecode) /* Note: this function is 7kb */ + *(.ramtext) /* .text* sections (code) */ *(.ramtext*) /* .text* sections (code) */ *(.data) /* .data sections */ @@ -63,7 +97,7 @@ SECTIONS _sbss = .; /* define a global symbol at bss start; used by startup code */ *(.bss) *(.bss*) - *(.dtcm_bss.*) /* Data Tightly Coupled Memory */ + *(.dtcm_bss.*) /* Data Tightly Coupled Memory */ *(.sbss) *(.sbss*) *(COMMON)