From 2100b6b21ef9c64a3cca1582dbd573c17c97bc4a Mon Sep 17 00:00:00 2001 From: BALATON Zoltan Date: Thu, 14 Jun 2018 02:17:00 +0200 Subject: [PATCH] sm501: Do not clear read only bits when writing registers When writing registers that have read only bits we have to avoid changing these bits as they may have non zero values. Make sure we use the correct masks to mask out read only and reserved bits when changing registers. Also remove extra spaces from dram_control and arbitration_control assignments. Signed-off-by: BALATON Zoltan Signed-off-by: David Gibson --- hw/display/sm501.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/hw/display/sm501.c b/hw/display/sm501.c index e47be99451..ca0840f6fa 100644 --- a/hw/display/sm501.c +++ b/hw/display/sm501.c @@ -836,27 +836,30 @@ static void sm501_system_config_write(void *opaque, hwaddr addr, switch (addr) { case SM501_SYSTEM_CONTROL: - s->system_control = value & 0xE300B8F7; + s->system_control &= 0x10DB0000; + s->system_control |= value & 0xEF00B8F7; break; case SM501_MISC_CONTROL: - s->misc_control = value & 0xFF7FFF20; + s->misc_control &= 0xEF; + s->misc_control |= value & 0xFF7FFF10; break; case SM501_GPIO31_0_CONTROL: s->gpio_31_0_control = value; break; case SM501_GPIO63_32_CONTROL: - s->gpio_63_32_control = value; + s->gpio_63_32_control = value & 0xFF80FFFF; break; case SM501_DRAM_CONTROL: s->local_mem_size_index = (value >> 13) & 0x7; /* TODO : check validity of size change */ - s->dram_control |= value & 0x7FFFFFC3; + s->dram_control &= 0x80000000; + s->dram_control |= value & 0x7FFFFFC3; break; case SM501_ARBTRTN_CONTROL: - s->arbitration_control = value & 0x37777777; + s->arbitration_control = value & 0x37777777; break; case SM501_IRQ_MASK: - s->irq_mask = value; + s->irq_mask = value & 0xFFDF3F5F; break; case SM501_MISC_TIMING: s->misc_timing = value & 0xF31F1FFF;