From 935fe442dc234c7b3fa52d346ced7a614696107e Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 15 Feb 2019 09:56:39 +0000 Subject: [PATCH] hw/intc/armv7m_nvic: Allow byte accesses to SHPR1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The code for handling the NVIC SHPR1 register intends to permit byte and halfword accesses (as the architecture requires). However the 'case' line for it only lists the base address of the register, so attempts to access bytes other than the first one end up in the "bad write" default logic. This bug was added accidentally when we split out the SHPR1 logic from SHPR2 and SHPR3 to support v6M. Fixes: 7c9140afd594 ("nvic: Handle ARMv6-M SCS reserved registers") Signed-off-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daudé --- The Zephyr RTOS happens to access SHPR1 byte at a time, which is how I spotted this. --- hw/intc/armv7m_nvic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c index 790a3d9584..ab822f4251 100644 --- a/hw/intc/armv7m_nvic.c +++ b/hw/intc/armv7m_nvic.c @@ -1841,7 +1841,7 @@ static MemTxResult nvic_sysreg_read(void *opaque, hwaddr addr, } } break; - case 0xd18: /* System Handler Priority (SHPR1) */ + case 0xd18 ... 0xd1b: /* System Handler Priority (SHPR1) */ if (!arm_feature(&s->cpu->env, ARM_FEATURE_M_MAIN)) { val = 0; break; @@ -1956,7 +1956,7 @@ static MemTxResult nvic_sysreg_write(void *opaque, hwaddr addr, } nvic_irq_update(s); return MEMTX_OK; - case 0xd18: /* System Handler Priority (SHPR1) */ + case 0xd18 ... 0xd1b: /* System Handler Priority (SHPR1) */ if (!arm_feature(&s->cpu->env, ARM_FEATURE_M_MAIN)) { return MEMTX_OK; }