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e95d8eaee2
The ARCH_FEATURES function ID is a 32-bit SMC call, which returns
a 32-bit result per the SMCCC spec. Current code is doing a 64-bit
comparison against -1 (SMCCC_RET_NOT_SUPPORTED) to detect that the
feature is unimplemented. That check doesn't work in a Hyper-V VM,
where the upper 32-bits are zero as allowed by the spec.
Cast the result as an 'int' so the comparison works. The change also
makes the code consistent with other similar checks in this file.
Fixes: 821b67fa46 ("firmware: smccc: Add ARCH_SOC_ID support")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
114 lines
2.9 KiB
C
114 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright 2020 Arm Limited
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*/
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#define pr_fmt(fmt) "SMCCC: SOC_ID: " fmt
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#include <linux/arm-smccc.h>
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#include <linux/bitfield.h>
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#include <linux/device.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/sys_soc.h>
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#define SMCCC_SOC_ID_JEP106_BANK_IDX_MASK GENMASK(30, 24)
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/*
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* As per the SMC Calling Convention specification v1.2 (ARM DEN 0028C)
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* Section 7.4 SMCCC_ARCH_SOC_ID bits[23:16] are JEP-106 identification
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* code with parity bit for the SiP. We can drop the parity bit.
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*/
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#define SMCCC_SOC_ID_JEP106_ID_CODE_MASK GENMASK(22, 16)
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#define SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK GENMASK(15, 0)
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#define JEP106_BANK_CONT_CODE(x) \
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(u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_BANK_IDX_MASK, (x)))
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#define JEP106_ID_CODE(x) \
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(u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_ID_CODE_MASK, (x)))
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#define IMP_DEF_SOC_ID(x) \
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(u16)(FIELD_GET(SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK, (x)))
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static struct soc_device *soc_dev;
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static struct soc_device_attribute *soc_dev_attr;
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static int __init smccc_soc_init(void)
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{
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struct arm_smccc_res res;
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int soc_id_rev, soc_id_version;
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static char soc_id_str[20], soc_id_rev_str[12];
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static char soc_id_jep106_id_str[12];
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if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2)
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return 0;
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if (arm_smccc_1_1_get_conduit() == SMCCC_CONDUIT_NONE) {
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pr_err("%s: invalid SMCCC conduit\n", __func__);
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return -EOPNOTSUPP;
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}
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arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
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ARM_SMCCC_ARCH_SOC_ID, &res);
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if ((int)res.a0 == SMCCC_RET_NOT_SUPPORTED) {
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pr_info("ARCH_SOC_ID not implemented, skipping ....\n");
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return 0;
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}
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if ((int)res.a0 < 0) {
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pr_info("ARCH_FEATURES(ARCH_SOC_ID) returned error: %lx\n",
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res.a0);
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return -EINVAL;
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}
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arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 0, &res);
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if ((int)res.a0 < 0) {
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pr_err("ARCH_SOC_ID(0) returned error: %lx\n", res.a0);
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return -EINVAL;
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}
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soc_id_version = res.a0;
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arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 1, &res);
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if ((int)res.a0 < 0) {
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pr_err("ARCH_SOC_ID(1) returned error: %lx\n", res.a0);
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return -EINVAL;
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}
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soc_id_rev = res.a0;
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soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
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if (!soc_dev_attr)
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return -ENOMEM;
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sprintf(soc_id_rev_str, "0x%08x", soc_id_rev);
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sprintf(soc_id_jep106_id_str, "jep106:%02x%02x",
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JEP106_BANK_CONT_CODE(soc_id_version),
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JEP106_ID_CODE(soc_id_version));
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sprintf(soc_id_str, "%s:%04x", soc_id_jep106_id_str,
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IMP_DEF_SOC_ID(soc_id_version));
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soc_dev_attr->soc_id = soc_id_str;
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soc_dev_attr->revision = soc_id_rev_str;
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soc_dev_attr->family = soc_id_jep106_id_str;
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soc_dev = soc_device_register(soc_dev_attr);
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if (IS_ERR(soc_dev)) {
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kfree(soc_dev_attr);
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return PTR_ERR(soc_dev);
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}
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pr_info("ID = %s Revision = %s\n", soc_dev_attr->soc_id,
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soc_dev_attr->revision);
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return 0;
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}
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module_init(smccc_soc_init);
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static void __exit smccc_soc_exit(void)
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{
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if (soc_dev)
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soc_device_unregister(soc_dev);
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kfree(soc_dev_attr);
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}
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module_exit(smccc_soc_exit);
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