From: Corey Hickey <bugfood-c@xxxxxxxxxx> Loading the amd_pmc module as: amd_pmc enable_stb=1 ...can result in the following messages in the kernel ring buffer: amd_pmc AMDI0009:00: SMU cmd failed. err: 0xff ioremap on RAM at 0x0000000000000000 - 0x0000000000ffffff WARNING: CPU: 10 PID: 2151 at arch/x86/mm/ioremap.c:217 __ioremap_caller+0x2cd/0x340 Additional debug shows that this happens when the calls to obtain S2D_PHYS_ADDR_LOW and S2D_PHYS_ADDR_HIGH return 0. According to Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>, this condition indicates that the STB is not available. In order to avoid the ioremap warning, and to help the user understand the situation, catch the invalid address and print an error. Link: https://lore.kernel.org/platform-driver-x86/c588ff5d-3e04-4549-9a86-284b9b4419ba@xxxxxxx Fixes: 3d7d407dfb05 ("platform/x86: amd-pmc: Add support for AMD Spill to DRAM STB feature") Signed-off-by: Corey Hickey <bugfood-c@xxxxxxxxxx> --- drivers/platform/x86/amd/pmc/pmc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c index bbb8edb62e00..5669f94c3d06 100644 --- a/drivers/platform/x86/amd/pmc/pmc.c +++ b/drivers/platform/x86/amd/pmc/pmc.c @@ -998,6 +998,11 @@ static int amd_pmc_s2d_init(struct amd_pmc_dev *dev) amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low, dev->s2d_msg_id, true); amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->s2d_msg_id, true); + if (!phys_addr_hi && !phys_addr_low) { + dev_err(dev->dev, "STB is not enabled on the system; disable enable_stb or contact system vendor\n"); + return -EINVAL; + } + stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low); /* Clear msg_port for other SMU operation */ -- 2.45.2