Commit 5f51c7ce authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: CPPC: Fix up I/O port access in cpc_read() 



The code as currently implemented does not work on big endian systems,
so fix it up.

Fixes: a2c8f92b ("ACPI: CPPC: Implement support for SystemIO registers")
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Suggested-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/linux-acpi/20220111092928.GA24968@kili/


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarHuang Rui <ray.huang@amd.com>
parent b35b6d4d

drivers/acpi/cppc_acpi.c

+3 −1
Original line number Diff line number Diff line
@@ -929,16 +929,18 @@ static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) 


	if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {

		u32 width = 8 << (reg->access_width - 1);

		u32 val_u32;

		acpi_status status;



		status = acpi_os_read_port((acpi_io_address)reg->address,

					   (u32 *)val, width);

					   &val_u32, width);

		if (ACPI_FAILURE(status)) {

			pr_debug("Error: Failed to read SystemIO port %llx\n",

				 reg->address);

			return -EFAULT;

		}



		*val = val_u32;

		return 0;

	} else if (reg->space_id == ACPI_ADR_SPACE_PLATFORM_COMM && pcc_ss_id >= 0)

		vaddr = GET_PCC_VADDR(reg->address, pcc_ss_id);