Fixes for PolarFire SoC eMMC/SD to stabilize and add read DMA support. Refactor the RISC-V boot/vector code for use on both 32-bit and 64-bit architectures.

Author: dgarske

arch.mk

@@ -542,7 +542,7 @@ ifeq ($(ARCH),RENESAS_RX)
 endif
 
 
-## RISCV
+## RISCV (32-bit)
 ifeq ($(ARCH),RISCV)
   CROSS_COMPILE?=riscv32-unknown-elf-
   ARCH_FLAGS=-march=rv32imac -mabi=ilp32 -mcmodel=medany
@@ -555,11 +555,12 @@ ifeq ($(ARCH),RISCV)
   CFLAGS +=-ffunction-sections -fdata-sections
   LDFLAGS+=-Wl,--gc-sections
 
-  OBJS+=src/boot_riscv.o src/vector_riscv.o
+  # Unified RISC-V boot code (32/64-bit via __riscv_xlen)
+  OBJS+=src/boot_riscv_start.o src/boot_riscv.o src/vector_riscv.o
   ARCH_FLASH_OFFSET=0x20010000
 endif
 
-## RISCV64
+## RISCV64 (64-bit)
 ifeq ($(ARCH),RISCV64)
   CROSS_COMPILE?=riscv64-unknown-elf-
   CFLAGS+=-DMMU -DWOLFBOOT_DUALBOOT
@@ -568,15 +569,16 @@ ifeq ($(ARCH),RISCV64)
   OBJS += src/gpt.o
   OBJS += src/disk.o
   ARCH_FLAGS=-march=rv64imafd -mabi=lp64d -mcmodel=medany
-  CFLAGS+=-fno-builtin-printf -DUSE_M_TIME -g -nostartfiles -DARCH_RISCV64
+  CFLAGS+=-fno-builtin-printf -DUSE_M_TIME -g -nostartfiles -DARCH_RISCV -DARCH_RISCV64
   CFLAGS+=$(ARCH_FLAGS)
   LDFLAGS+=$(ARCH_FLAGS)
 
   # Prune unused functions and data
   CFLAGS +=-ffunction-sections -fdata-sections
   LDFLAGS+=-Wl,--gc-sections
 
-  OBJS+=src/boot_riscv64_start.o src/boot_riscv64.o src/vector_riscv64.o
+  # Unified RISC-V boot code (32/64-bit via __riscv_xlen)
+  OBJS+=src/boot_riscv_start.o src/boot_riscv.o src/vector_riscv.o
 
   CFLAGS+=-DWOLFBOOT_FDT
   OBJS+=src/fdt.o

config/examples/polarfire_mpfs250.config

@@ -48,8 +48,8 @@ WOLFBOOT_LOAD_ADDRESS?=0x8E000000
 WOLFBOOT_NO_PARTITIONS=1
 CFLAGS_EXTRA+=-DBOOT_PART_A=1
 CFLAGS_EXTRA+=-DBOOT_PART_B=2
-# Speed up disk partition read (1MB chunks)
-CFLAGS_EXTRA+=-DDISK_BLOCK_SIZE=0x100000
+# Speed up disk partition read (512KB chunks)
+CFLAGS_EXTRA+=-DDISK_BLOCK_SIZE=0x80000
 
 # DTS (Device Tree)
 WOLFBOOT_LOAD_DTS_ADDRESS?=0x8A000000

docs/Targets.md

@@ -1034,7 +1034,7 @@ set architecture riscv:rv64
 ### PolarFire Example Boot Output
 
 ```
-wolfBoot Version: 2.7.0 (Dec 22 2025 14:14:37)
+wolfBoot Version: 2.7.0 (Dec 29 2025 11:34:01)
 Reading MBR...
 Found GPT PTE at sector 1
 Found valid boot signature in MBR
@@ -1054,19 +1054,18 @@ Checking secondary OS image in 0,2...
 Versions, A:1 B:1
 Load address 0x8E000000
 Attempting boot from P:A
-Boot partition: 0x801FFDA0 (sz 19767000, ver 0x1, type 0x601)
-Loading image from disk...done.
-Boot partition: 0x8E000000 (sz 19767000, ver 0x1, type 0x601)
-Checking image integrity...done.
-Verifying image signature...done.
+Boot partition: 0x801FFD80 (sz 19767004, ver 0x1, type 0x601)
+Loading image from disk...done. (846 ms)
+Boot partition: 0x8E000000 (sz 19767004, ver 0x1, type 0x601)
+Checking image integrity...done. (1507 ms)
+Verifying image signature...done. (68 ms)
 Firmware Valid.
-Flattened uImage Tree: Version 17, Size 19767000
+Flattened uImage Tree: Version 17, Size 19767004
 Loading Image kernel-1: 0x8E0002C8 -> 0x80200000 (19745280 bytes)
 Image kernel-1: 0x80200000 (19745280 bytes)
 Loading Image fdt-1: 0x8F2D4DCC -> 0x8A000000 (19897 bytes)
 Image fdt-1: 0x8A000000 (19897 bytes)
 Loading DTS: 0x8A000000 -> 0x8A000000 (19897 bytes)
-Loading elf at 0x80200000
 Invalid elf, falling back to raw binary
 Booting at 80200000
 [    0.000000] Linux version 6.12.22-linux4microchip+fpga-2025.07-g032a7095303a (oe-user@oe-host) (riscv64-oe-linux-gcc (GCC) 13.3.0, GNU ld (GNU Binutils) 2.42.0.20240723) #1 SMP Tue Jul 22 10:04:20 UTC 2025
@@ -1078,14 +1077,13 @@ Booting at 80200000
 [    0.000000] SBI RFENCE extension detected
 [    0.000000] SBI SRST extension detected
 [    0.000000] earlycon: ns16550a0 at MMIO32 0x0000000020100000 (options '115200n8')
+[    0.000000] printk: legacy bootconsole [ns16550a0] enabled
 ...
 ```
 
 ### PolarFire TODO
 
 * Add eMMC/SD features:
-  - Improve mmc_delay and timeout handling
-  - DMA read support
   - Write support
   - eMMC support (not just SD)
 * Add support for reading serial number and modifying ethernet MAC in device tree