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/* SPDX-License-Identifier: GPL-2.0-only */
#include <cpu/x86/msr.h>
#include <cpu/x86/mtrr.h>
#include <cpu/amd/mtrr.h>
#include <cpu/amd/msr.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/smm.h>
#include <cpu/x86/smi_deprecated.h>
#include <string.h>
void smm_init(void)
{
msr_t msr, syscfg_orig, mtrr_aseg_orig;
/* Back up MSRs for later restore */
syscfg_orig = rdmsr(SYSCFG_MSR);
mtrr_aseg_orig = rdmsr(MTRR_FIX_16K_A0000);
/* MTRR changes don't like an enabled cache */
disable_cache();
msr = syscfg_orig;
/* Allow changes to MTRR extended attributes */
msr.lo |= SYSCFG_MSR_MtrrFixDramModEn;
/* turn the extended attributes off until we fix
* them so A0000 is routed to memory
*/
msr.lo &= ~SYSCFG_MSR_MtrrFixDramEn;
wrmsr(SYSCFG_MSR, msr);
/* set DRAM access to 0xa0000 */
msr.lo = 0x18181818;
msr.hi = 0x18181818;
wrmsr(MTRR_FIX_16K_A0000, msr);
/* enable the extended features */
msr = syscfg_orig;
msr.lo |= SYSCFG_MSR_MtrrFixDramModEn;
msr.lo |= SYSCFG_MSR_MtrrFixDramEn;
wrmsr(SYSCFG_MSR, msr);
enable_cache();
/* copy the real SMM handler */
memcpy((void *)SMM_BASE, _binary_smm_start, _binary_smm_end - _binary_smm_start);
wbinvd();
disable_cache();
/* Restore SYSCFG and MTRR */
wrmsr(SYSCFG_MSR, syscfg_orig);
wrmsr(MTRR_FIX_16K_A0000, mtrr_aseg_orig);
enable_cache();
/* CPU MSR are set in CPU init */
}
void smm_init_completion(void)
{
}
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