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#include <console/console.h>
#include <device/device.h>
#include <arch/cpu.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/msr.h>
#include <cpu/amd/mtrr.h>
#include <cpu/x86/cache.h>
/* These will likely move to some device node or cbmem. */
static uint64_t amd_topmem = 0;
static uint64_t amd_topmem2 = 0;
uint64_t bsp_topmem(void)
{
return amd_topmem;
}
uint64_t bsp_topmem2(void)
{
return amd_topmem2;
}
/* Take a copy of BSP CPUs TOP_MEM and TOP_MEM2 registers,
* so they can be distributed to AP CPUs. Not strictly MTRRs,
* but this is not that bad a place to have this code.
*/
void setup_bsp_ramtop(void)
{
msr_t msr, msr2;
/* TOP_MEM: the top of DRAM below 4G */
msr = rdmsr(TOP_MEM);
printk(BIOS_INFO,
"%s, TOP MEM: msr.lo = 0x%08x, msr.hi = 0x%08x\n",
__func__, msr.lo, msr.hi);
/* TOP_MEM2: the top of DRAM above 4G */
msr2 = rdmsr(TOP_MEM2);
printk(BIOS_INFO,
"%s, TOP MEM2: msr.lo = 0x%08x, msr.hi = 0x%08x\n",
__func__, msr2.lo, msr2.hi);
amd_topmem = (uint64_t) msr.hi<<32 | msr.lo;
amd_topmem2 = (uint64_t) msr2.hi<<32 | msr2.lo;
}
static void setup_ap_ramtop(void)
{
msr_t msr;
uint64_t v;
v = bsp_topmem();
if (!v)
return;
msr.hi = v >> 32;
msr.lo = (uint32_t) v;
wrmsr(TOP_MEM, msr);
v = bsp_topmem2();
msr.hi = v >> 32;
msr.lo = (uint32_t) v;
wrmsr(TOP_MEM2, msr);
}
void amd_setup_mtrrs(void)
{
unsigned long address_bits;
unsigned long i;
msr_t msr, sys_cfg;
// Test if this CPU is a Fam 0Fh rev. F or later
const int cpu_id = cpuid_eax(0x80000001);
printk(BIOS_SPEW, "CPU ID 0x80000001: %x\n", cpu_id);
const int has_tom2wb =
(((cpu_id>>20 )&0xf) > 0) || // ExtendedFamily > 0
((((cpu_id>>8 )&0xf) == 0xf) && // Family == 0F
(((cpu_id>>16)&0xf) >= 0x4)); // Rev>=F deduced from rev tables
if(has_tom2wb)
printk(BIOS_DEBUG, "CPU is Fam 0Fh rev.F or later. We can use TOM2WB for any memory above 4GB\n");
/* Enable the access to AMD RdDram and WrDram extension bits */
disable_cache();
sys_cfg = rdmsr(SYSCFG_MSR);
sys_cfg.lo |= SYSCFG_MSR_MtrrFixDramModEn;
wrmsr(SYSCFG_MSR, sys_cfg);
enable_cache();
/* Setup fixed MTRRs, but do not enable them just yet. */
x86_setup_fixed_mtrrs_no_enable();
disable_cache();
setup_ap_ramtop();
/* if DRAM above 4GB: set SYSCFG_MSR_TOM2En and SYSCFG_MSR_TOM2WB */
sys_cfg.lo &= ~(SYSCFG_MSR_TOM2En | SYSCFG_MSR_TOM2WB);
if (bsp_topmem2() > (uint64_t)1<<32) {
sys_cfg.lo |= SYSCFG_MSR_TOM2En;
if(has_tom2wb)
sys_cfg.lo |= SYSCFG_MSR_TOM2WB;
}
/* zero the IORR's before we enable to prevent
* undefined side effects.
*/
msr.lo = msr.hi = 0;
for(i = IORR_FIRST; i <= IORR_LAST; i++) {
wrmsr(i, msr);
}
/* Enable Variable Mtrrs
* Enable the RdMem and WrMem bits in the fixed mtrrs.
* Disable access to the RdMem and WrMem in the fixed mtrr.
*/
sys_cfg.lo |= SYSCFG_MSR_MtrrVarDramEn | SYSCFG_MSR_MtrrFixDramEn;
sys_cfg.lo &= ~SYSCFG_MSR_MtrrFixDramModEn;
wrmsr(SYSCFG_MSR, sys_cfg);
enable_fixed_mtrr();
enable_cache();
address_bits = CONFIG_CPU_ADDR_BITS; //K8 could be 40, and GH could be 48
/* AMD specific cpuid function to query number of address bits */
if (cpuid_eax(0x80000000) >= 0x80000008) {
address_bits = cpuid_eax(0x80000008) & 0xff;
}
/* Now that I have mapped what is memory and what is not
* Set up the mtrrs so we can cache the memory.
*/
// Rev. F K8 supports has SYSCFG_MSR_TOM2WB and doesn't need
// variable MTRR to span memory above 4GB
// Lower revisions K8 need variable MTRR over 4GB
x86_setup_var_mtrrs(address_bits, has_tom2wb ? 0 : 1);
}
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