From 5e06ef4015ceacadc17d395db6ccca2e77b0c141 Mon Sep 17 00:00:00 2001
From: James Turton <james.turton@gmx.com>
Date: Thu, 1 Sep 2022 23:35:34 +0200
Subject: [PATCH] rp: Don't aboard program when attaching

Reading the sfdp parameter table in the flash causes the spi peripheral
to be reconfigure, and, while the previous configuration is restored,
this causes the running program to be aboarded. Reading the sfdp table
before erasing the memory could be considered safe as we are going to be
modifying the flash anyway.
---
 src/target/rp.c | 42 ++++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/src/target/rp.c b/src/target/rp.c
index 66aab4e..c3ba076 100644
--- a/src/target/rp.c
+++ b/src/target/rp.c
@@ -174,31 +174,21 @@ static void rp_add_flash(target *t)
 		return;
 	}
 
-	rp_flash_prepare(t);
-	spi_parameters_s spi_parameters;
-	if (!sfdp_read_parameters(t, &spi_parameters, rp_spi_read_sfdp)) {
-		/* SFDP readout failed, so make some assumptions and hope for the best. */
-		spi_parameters.page_size = 256U;
-		spi_parameters.sector_size = 4096U;
-		spi_parameters.capacity = rp_get_flash_length(t);
-		spi_parameters.sector_erase_opcode = SPI_FLASH_CMD_SECTOR_ERASE;
-	}
-	rp_flash_resume(t);
-
-	DEBUG_INFO("Flash size: %zu MB\n", spi_parameters.capacity / (1024U * 1024U));
-
+	/* Make some assumptions and hope for the best. */
 	target_flash_s *const f = &flash->f;
 	f->start = RP_XIP_FLASH_BASE;
-	f->length = spi_parameters.capacity;
-	f->blocksize = spi_parameters.sector_size;
+	f->length = rp_get_flash_length(t);
+	f->blocksize = 4096U;
 	f->erase = rp_flash_erase;
 	f->write = rp_flash_write;
 	f->writesize = 2048; /* Max buffer size used otherwise */
 	f->erased = 0xffU;
 	target_add_flash(t, f);
 
-	flash->page_size = spi_parameters.page_size;
-	flash->sector_erase_opcode = spi_parameters.sector_erase_opcode;
+	DEBUG_INFO("Flash size: %d MB\n", f->length / (1024U * 1024U));
+
+	flash->page_size = 256U;
+	flash->sector_erase_opcode = SPI_FLASH_CMD_SECTOR_ERASE;
 }
 
 bool rp_probe(target *t)
@@ -220,6 +210,8 @@ bool rp_probe(target *t)
 		DEBUG_WARN("calloc: failed in %s\n", __func__);
 		return false;
 	}
+	priv_storage->is_prepared = false;
+	priv_storage->is_monitor = false;
 	t->target_storage = (void *)priv_storage;
 
 	t->mass_erase = rp_mass_erase;
@@ -387,12 +379,25 @@ static bool rp_flash_erase(target_flash_s *f, target_addr_t addr, size_t len)
 {
 	DEBUG_INFO("Erase addr 0x%08" PRIx32 " len 0x%" PRIx32 "\n", addr, (uint32_t)len);
 	target *t = f->t;
+
+	/* Update our assumptions with the SFDP params */
+	rp_flash_prepare(t);
+	spi_parameters_s spi_parameters;
+	rp_flash_s *flash = (rp_flash_s *)f;
+	if (sfdp_read_parameters(t, &spi_parameters, rp_spi_read_sfdp)) {
+		 f->blocksize = spi_parameters.sector_size;
+	     flash->page_size = spi_parameters.page_size;
+	     flash->sector_erase_opcode = spi_parameters.sector_erase_opcode;
+	}
+
 	if (addr & (f->blocksize - 1)) {
 		DEBUG_WARN("Unaligned erase\n");
+		rp_flash_resume(t);
 		return false;
 	}
 	if ((addr < f->start) || (addr >= f->start + f->length)) {
 		DEBUG_WARN("Address is invalid\n");
+		rp_flash_resume(t);
 		return false;
 	}
 	addr -= f->start;
@@ -404,7 +409,6 @@ static bool rp_flash_erase(target_flash_s *f, target_addr_t addr, size_t len)
 	platform_timeout_set(&timeout, 500);
 
 	/* erase */
-	rp_flash_prepare(t);
 	bool ret = false;
 	while (len) {
 		if (len >= FLASHSIZE_64K_BLOCK) {
@@ -428,7 +432,6 @@ static bool rp_flash_erase(target_flash_s *f, target_addr_t addr, size_t len)
 			len -= chunk;
 			addr += chunk;
 		} else {
-			rp_flash_s *flash = (rp_flash_s *)f;
 			ps->regs[0] = addr;
 			ps->regs[1] = len;
 			ps->regs[2] = f->blocksize;
@@ -568,7 +571,6 @@ static uint32_t rp_get_flash_length(target *t)
 	uint32_t bootsec[16];
 	size_t i;
 
-	rp_flash_resume(t);
 	target_mem_read(t, bootsec, RP_XIP_FLASH_BASE, sizeof(bootsec));
 	for (i = 0; i < 16; i++) {
 		if ((bootsec[i] != 0x00) && (bootsec[i] != 0xff))