mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-28 07:31:15 +00:00
powerpc/mpc85xx: Rewrite spin table to comply with ePAPR v1.1
Move spin table to cached memory to comply with ePAPR v1.1. Load R3 with 64-bit value if CONFIG_SYS_PPC64 is defined. 'M' bit is set for DDR TLB to maintain cache coherence. See details in doc/README.mpc85xx-spin-table. Signed-off-by: York Sun <yorksun@freescale.com> Signed-off-by: Andy Fleming <afleming@freescale.com>
This commit is contained in:
parent
3f0997b325
commit
ffd06e0231
8 changed files with 190 additions and 119 deletions
6
README
6
README
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@ -363,6 +363,12 @@ The following options need to be configured:
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ICache only when Code runs from RAM.
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- 85xx CPU Options:
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CONFIG_SYS_PPC64
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Specifies that the core is a 64-bit PowerPC implementation (implements
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the "64" category of the Power ISA). This is necessary for ePAPR
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compliance, among other possible reasons.
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CONFIG_SYS_FSL_TBCLK_DIV
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Defines the core time base clock divider ratio compared to the
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@ -47,7 +47,7 @@ extern void ft_srio_setup(void *blob);
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void ft_fixup_cpu(void *blob, u64 memory_limit)
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{
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int off;
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ulong spin_tbl_addr = get_spin_phys_addr();
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phys_addr_t spin_tbl_addr = get_spin_phys_addr();
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u32 bootpg = determine_mp_bootpg(NULL);
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u32 id = get_my_id();
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const char *enable_method;
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@ -97,7 +97,16 @@ void ft_fixup_cpu(void *blob, u64 memory_limit)
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if ((u64)bootpg < memory_limit) {
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off = fdt_add_mem_rsv(blob, bootpg, (u64)4096);
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if (off < 0)
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printf("%s: %s\n", __FUNCTION__, fdt_strerror(off));
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printf("Failed to reserve memory for bootpg: %s\n",
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fdt_strerror(off));
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}
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/* Reserve spin table page */
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if (spin_tbl_addr < memory_limit) {
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off = fdt_add_mem_rsv(blob,
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(spin_tbl_addr & ~0xffful), 4096);
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if (off < 0)
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printf("Failed to reserve memory for spin table: %s\n",
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fdt_strerror(off));
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}
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}
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#endif
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@ -33,6 +33,8 @@
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DECLARE_GLOBAL_DATA_PTR;
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u32 fsl_ddr_get_intl3r(void);
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extern u32 __spin_table[];
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u32 get_my_id()
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{
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return mfspr(SPRN_PIR);
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@ -78,10 +80,10 @@ int cpu_status(int nr)
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return 0;
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if (nr == id) {
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table = (u32 *)get_spin_virt_addr();
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table = (u32 *)&__spin_table;
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printf("table base @ 0x%p\n", table);
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} else {
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table = (u32 *)get_spin_virt_addr() + nr * NUM_BOOT_ENTRY;
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table = (u32 *)&__spin_table + nr * NUM_BOOT_ENTRY;
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printf("Running on cpu %d\n", id);
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printf("\n");
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printf("table @ 0x%p\n", table);
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@ -154,7 +156,7 @@ static u8 boot_entry_map[4] = {
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int cpu_release(int nr, int argc, char * const argv[])
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{
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u32 i, val, *table = (u32 *)get_spin_virt_addr() + nr * NUM_BOOT_ENTRY;
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u32 i, val, *table = (u32 *)&__spin_table + nr * NUM_BOOT_ENTRY;
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u64 boot_addr;
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if (hold_cores_in_reset(1))
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@ -200,11 +202,11 @@ u32 determine_mp_bootpg(unsigned int *pagesize)
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struct law_entry e;
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#endif
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/* if we have 4G or more of memory, put the boot page at 4Gb-4k */
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if ((u64)gd->ram_size > 0xfffff000)
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bootpg = 0xfffff000;
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else
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bootpg = gd->ram_size - 4096;
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/* use last 4K of mapped memory */
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bootpg = ((gd->ram_size > CONFIG_MAX_MEM_MAPPED) ?
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CONFIG_MAX_MEM_MAPPED : gd->ram_size) +
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CONFIG_SYS_SDRAM_BASE - 4096;
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if (pagesize)
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*pagesize = 4096;
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@ -255,29 +257,16 @@ u32 determine_mp_bootpg(unsigned int *pagesize)
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return bootpg;
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}
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ulong get_spin_phys_addr(void)
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phys_addr_t get_spin_phys_addr(void)
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{
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extern ulong __secondary_start_page;
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extern ulong __spin_table;
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return (determine_mp_bootpg() +
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(ulong)&__spin_table - (ulong)&__secondary_start_page);
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}
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ulong get_spin_virt_addr(void)
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{
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extern ulong __secondary_start_page;
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extern ulong __spin_table;
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return (CONFIG_BPTR_VIRT_ADDR +
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(ulong)&__spin_table - (ulong)&__secondary_start_page);
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return virt_to_phys(&__spin_table);
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}
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#ifdef CONFIG_FSL_CORENET
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static void plat_mp_up(unsigned long bootpg, unsigned int pagesize)
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{
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u32 cpu_up_mask, whoami, brsize = LAW_SIZE_4K;
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u32 *table = (u32 *)get_spin_virt_addr();
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u32 *table = (u32 *)&__spin_table;
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volatile ccsr_gur_t *gur;
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volatile ccsr_local_t *ccm;
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volatile ccsr_rcpm_t *rcpm;
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@ -356,7 +345,7 @@ static void plat_mp_up(unsigned long bootpg, unsigned int pagesize)
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static void plat_mp_up(unsigned long bootpg, unsigned int pagesize)
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{
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u32 up, cpu_up_mask, whoami;
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u32 *table = (u32 *)get_spin_virt_addr();
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u32 *table = (u32 *)&__spin_table;
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volatile u32 bpcr;
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volatile ccsr_local_ecm_t *ecm = (void *)(CONFIG_SYS_MPC85xx_ECM_ADDR);
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volatile ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
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@ -440,10 +429,11 @@ void cpu_mp_lmb_reserve(struct lmb *lmb)
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void setup_mp(void)
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{
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extern ulong __secondary_start_page;
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extern ulong __bootpg_addr;
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extern u32 __secondary_start_page;
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extern u32 __bootpg_addr, __spin_table_addr, __second_half_boot_page;
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ulong fixup = (ulong)&__secondary_start_page;
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int i;
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ulong fixup = (u32)&__secondary_start_page;
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u32 bootpg, bootpg_map, pagesize;
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bootpg = determine_mp_bootpg(&pagesize);
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@ -464,11 +454,20 @@ void setup_mp(void)
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if (hold_cores_in_reset(0))
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return;
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/* Store the bootpg's SDRAM address for use by secondary CPU cores */
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__bootpg_addr = bootpg;
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/*
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* Store the bootpg's cache-able half address for use by secondary
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* CPU cores to continue to boot
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*/
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__bootpg_addr = (u32)virt_to_phys(&__second_half_boot_page);
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/* Store spin table's physical address for use by secondary cores */
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__spin_table_addr = (u32)get_spin_phys_addr();
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/* flush bootpg it before copying invalidate any staled cacheline */
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flush_cache(bootpg, 4096);
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/* look for the tlb covering the reset page, there better be one */
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int i = find_tlb_idx((void *)CONFIG_BPTR_VIRT_ADDR, 1);
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i = find_tlb_idx((void *)CONFIG_BPTR_VIRT_ADDR, 1);
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/* we found a match */
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if (i != -1) {
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@ -3,8 +3,7 @@
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#include <asm/mp.h>
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ulong get_spin_phys_addr(void);
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ulong get_spin_virt_addr(void);
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phys_addr_t get_spin_phys_addr(void);
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u32 get_my_id(void);
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int hold_cores_in_reset(int verbose);
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@ -16,7 +15,7 @@ int hold_cores_in_reset(int verbose);
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#define BOOT_ENTRY_PIR 5
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#define BOOT_ENTRY_R6_UPPER 6
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#define BOOT_ENTRY_R6_LOWER 7
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#define NUM_BOOT_ENTRY 8
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#define NUM_BOOT_ENTRY 16 /* pad to 64 bytes */
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#define SIZE_BOOT_ENTRY (NUM_BOOT_ENTRY * sizeof(u32))
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#endif
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@ -150,10 +150,14 @@ __secondary_start_page:
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#define toreset(x) (x - __secondary_start_page + 0xfffff000)
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/* get our PIR to figure out our table entry */
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lis r3,toreset(__spin_table)@h
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ori r3,r3,toreset(__spin_table)@l
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lis r3,toreset(__spin_table_addr)@h
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ori r3,r3,toreset(__spin_table_addr)@l
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lwz r3,0(r3)
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/* r10 has the base address for the entry */
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/*
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* r10 has the base address for the entry.
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* we cannot access it yet before setting up a new TLB
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*/
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mfspr r0,SPRN_PIR
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#if defined(CONFIG_E6500)
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/*
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@ -180,7 +184,7 @@ __secondary_start_page:
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#else
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mr r4,r0
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#endif
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slwi r8,r4,5
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slwi r8,r4,6 /* spin table is padded to 64 byte */
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add r10,r3,r8
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#ifdef CONFIG_E6500
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@ -277,73 +281,111 @@ __secondary_start_page:
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beq 2b
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#endif
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3:
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/* setup mapping for the spin table, WIMGE=0b00100 */
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lis r13,toreset(__spin_table_addr)@h
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ori r13,r13,toreset(__spin_table_addr)@l
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lwz r13,0(r13)
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/* mask by 4K */
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rlwinm r13,r13,0,0,19
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#define EPAPR_MAGIC (0x45504150)
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lis r11,(MAS0_TLBSEL(1)|MAS0_ESEL(1))@h
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mtspr SPRN_MAS0,r11
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lis r11,(MAS1_VALID|MAS1_IPROT)@h
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ori r11,r11,(MAS1_TS|MAS1_TSIZE(BOOKE_PAGESZ_4K))@l
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mtspr SPRN_MAS1,r11
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oris r11,r13,(MAS2_M|MAS2_G)@h
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ori r11,r13,(MAS2_M|MAS2_G)@l
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mtspr SPRN_MAS2,r11
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oris r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@h
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ori r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@l
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mtspr SPRN_MAS3,r11
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li r11,0
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mtspr SPRN_MAS7,r11
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tlbwe
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/*
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* __bootpg_addr has the address of __second_half_boot_page
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* jump there in AS=1 space with cache enabled
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*/
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lis r13,toreset(__bootpg_addr)@h
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ori r13,r13,toreset(__bootpg_addr)@l
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lwz r11,0(r13)
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mtspr SPRN_SRR0,r11
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mfmsr r13
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ori r12,r13,MSR_IS|MSR_DS@l
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mtspr SPRN_SRR1,r12
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rfi
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/*
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* Allocate some space for the SDRAM address of the bootpg.
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* This variable has to be in the boot page so that it can
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* be accessed by secondary cores when they come out of reset.
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*/
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.align L1_CACHE_SHIFT
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.globl __bootpg_addr
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__bootpg_addr:
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.long 0
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.global __spin_table_addr
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__spin_table_addr:
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.long 0
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/*
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* This variable is set by cpu_init_r() after parsing hwconfig
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* to enable workaround for erratum NMG_CPU_A011.
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*/
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.align L1_CACHE_SHIFT
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.global enable_cpu_a011_workaround
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enable_cpu_a011_workaround:
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.long 1
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/* Fill in the empty space. The actual reset vector is
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* the last word of the page */
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__secondary_start_code_end:
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.space 4092 - (__secondary_start_code_end - __secondary_start_page)
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__secondary_reset_vector:
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b __secondary_start_page
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/* this is a separated page for the spin table and cacheable boot code */
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.align L1_CACHE_SHIFT
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.global __second_half_boot_page
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__second_half_boot_page:
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#define EPAPR_MAGIC 0x45504150
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#define ENTRY_ADDR_UPPER 0
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#define ENTRY_ADDR_LOWER 4
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#define ENTRY_R3_UPPER 8
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#define ENTRY_R3_LOWER 12
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#define ENTRY_RESV 16
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#define ENTRY_PIR 20
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#define ENTRY_R6_UPPER 24
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#define ENTRY_R6_LOWER 28
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#define ENTRY_SIZE 32
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/* setup the entry */
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#define ENTRY_SIZE 64
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/*
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* setup the entry
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* r10 has the base address of the spin table.
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* spin table is defined as
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* struct {
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* uint64_t entry_addr;
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* uint64_t r3;
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* uint32_t rsvd1;
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* uint32_t pir;
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* };
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* we pad this struct to 64 bytes so each entry is in its own cacheline
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*/
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li r3,0
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li r8,1
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stw r4,ENTRY_PIR(r10)
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mfspr r4,SPRN_PIR
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stw r3,ENTRY_ADDR_UPPER(r10)
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stw r8,ENTRY_ADDR_LOWER(r10)
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stw r3,ENTRY_R3_UPPER(r10)
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stw r4,ENTRY_R3_LOWER(r10)
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stw r3,ENTRY_R6_UPPER(r10)
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stw r3,ENTRY_R6_LOWER(r10)
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/* load r13 with the address of the 'bootpg' in SDRAM */
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lis r13,toreset(__bootpg_addr)@h
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ori r13,r13,toreset(__bootpg_addr)@l
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lwz r13,0(r13)
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/* setup mapping for AS = 1, and jump there */
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lis r11,(MAS0_TLBSEL(1)|MAS0_ESEL(1))@h
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mtspr SPRN_MAS0,r11
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lis r11,(MAS1_VALID|MAS1_IPROT)@h
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ori r11,r11,(MAS1_TS|MAS1_TSIZE(BOOKE_PAGESZ_4K))@l
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mtspr SPRN_MAS1,r11
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oris r11,r13,(MAS2_I|MAS2_G)@h
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ori r11,r13,(MAS2_I|MAS2_G)@l
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mtspr SPRN_MAS2,r11
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oris r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@h
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ori r11,r13,(MAS3_SX|MAS3_SW|MAS3_SR)@l
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mtspr SPRN_MAS3,r11
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tlbwe
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bl 1f
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1: mflr r11
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/*
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* OR in 0xfff to create a mask of the bootpg SDRAM address. We use
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* this mask to fixup the cpu spin table and the address that we want
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* to jump to, eg change them from 0xfffffxxx to 0x7ffffxxx if the
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* bootpg is at 0x7ffff000 in SDRAM.
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*/
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ori r13,r13,0xfff
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and r11, r11, r13
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and r10, r10, r13
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addi r11,r11,(2f-1b)
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mfmsr r13
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ori r12,r13,MSR_IS|MSR_DS@l
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mtspr SPRN_SRR0,r11
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mtspr SPRN_SRR1,r12
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rfi
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stw r3,ENTRY_RESV(r10)
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stw r4,ENTRY_PIR(r10)
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msync
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stw r8,ENTRY_ADDR_LOWER(r10)
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/* spin waiting for addr */
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2:
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lwz r4,ENTRY_ADDR_LOWER(r10)
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3: lwz r4,ENTRY_ADDR_LOWER(r10)
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andi. r11,r4,1
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bne 2b
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bne 3b
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isync
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/* setup IVORs to match fixed offsets */
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@ -362,8 +404,17 @@ __secondary_start_page:
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/* mask by ~64M to setup our tlb we will jump to */
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rlwinm r12,r4,0,0,5
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/* setup r3, r4, r5, r6, r7, r8, r9 */
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/*
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* setup r3, r4, r5, r6, r7, r8, r9
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* r3 contains the value to put in the r3 register at secondary cpu
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* entry. The high 32-bits are ignored on 32-bit chip implementations.
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* 64-bit chip implementations however shall load all 64-bits
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*/
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#ifdef CONFIG_SYS_PPC64
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ld r3,ENTRY_R3_UPPER(r10)
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#else
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lwz r3,ENTRY_R3_LOWER(r10)
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#endif
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li r4,0
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li r5,0
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li r6,0
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@ -404,32 +455,10 @@ __secondary_start_page:
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mtspr SPRN_SRR1,r13
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rfi
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/*
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* Allocate some space for the SDRAM address of the bootpg.
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* This variable has to be in the boot page so that it can
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* be accessed by secondary cores when they come out of reset.
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*/
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.globl __bootpg_addr
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__bootpg_addr:
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.long 0
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.align L1_CACHE_SHIFT
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.align 6
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.globl __spin_table
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__spin_table:
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.space CONFIG_MAX_CPUS*ENTRY_SIZE
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/*
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* This variable is set by cpu_init_r() after parsing hwconfig
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* to enable workaround for erratum NMG_CPU_A011.
|
||||
*/
|
||||
.align L1_CACHE_SHIFT
|
||||
.global enable_cpu_a011_workaround
|
||||
enable_cpu_a011_workaround:
|
||||
.long 1
|
||||
|
||||
/* Fill in the empty space. The actual reset vector is
|
||||
* the last word of the page */
|
||||
__secondary_start_code_end:
|
||||
.space 4092 - (__secondary_start_code_end - __secondary_start_page)
|
||||
__secondary_reset_vector:
|
||||
b __secondary_start_page
|
||||
__spin_table_end:
|
||||
.space 4096 - (__spin_table_end - __spin_table)
|
||||
|
|
|
@ -249,7 +249,7 @@ setup_ddr_tlbs_phys(phys_addr_t p_addr, unsigned int memsize_in_meg)
|
|||
{
|
||||
int i;
|
||||
unsigned int tlb_size;
|
||||
unsigned int wimge = 0;
|
||||
unsigned int wimge = MAS2_M;
|
||||
unsigned int ram_tlb_address = (unsigned int)CONFIG_SYS_DDR_SDRAM_BASE;
|
||||
unsigned int max_cam;
|
||||
u64 size, memsize = (u64)memsize_in_meg << 20;
|
||||
|
|
|
@ -416,6 +416,7 @@
|
|||
#define CONFIG_SYS_FSL_ERRATUM_SRIO_A004034
|
||||
|
||||
#elif defined(CONFIG_PPC_P5020) /* also supports P5010 */
|
||||
#define CONFIG_SYS_PPC64 /* 64-bit core */
|
||||
#define CONFIG_SYS_FSL_QORIQ_CHASSIS1
|
||||
#define CONFIG_MAX_CPUS 2
|
||||
#define CONFIG_SYS_FSL_NUM_CC_PLLS 2
|
||||
|
@ -485,6 +486,7 @@
|
|||
#define CONFIG_SYS_FSL_ERRATUM_ESDHC111
|
||||
|
||||
#elif defined(CONFIG_PPC_T4240)
|
||||
#define CONFIG_SYS_PPC64 /* 64-bit core */
|
||||
#define CONFIG_FSL_CORENET /* Freescale CoreNet platform */
|
||||
#define CONFIG_SYS_FSL_QORIQ_CHASSIS2 /* Freescale Chassis generation 2 */
|
||||
#define CONFIG_SYS_FSL_QMAN_V3 /* QMAN version 3 */
|
||||
|
@ -516,6 +518,7 @@
|
|||
#define CONFIG_SYS_CCSRBAR_DEFAULT 0xfe000000
|
||||
|
||||
#elif defined(CONFIG_PPC_B4860)
|
||||
#define CONFIG_SYS_PPC64 /* 64-bit core */
|
||||
#define CONFIG_FSL_CORENET /* Freescale CoreNet platform */
|
||||
#define CONFIG_SYS_FSL_QORIQ_CHASSIS2 /* Freescale Chassis generation 2 */
|
||||
#define CONFIG_SYS_FSL_QMAN_V3 /* QMAN version 3 */
|
||||
|
|
26
doc/README.mpc85xx-spin-table
Normal file
26
doc/README.mpc85xx-spin-table
Normal file
|
@ -0,0 +1,26 @@
|
|||
Spin table in cache
|
||||
=====================================
|
||||
As specified by ePAPR v1.1, the spin table needs to be in cached memory. After
|
||||
DDR is initialized and U-boot relocates itself into DDR, the spin table is
|
||||
accessible for core 0. It is part of release.S, within 4KB range after
|
||||
__secondary_start_page. For other cores to use the spin table, the booting
|
||||
process is described below:
|
||||
|
||||
Core 0 sets up the reset page on the top 4K of memory (or 4GB if total memory
|
||||
is more than 4GB), and creates a TLB to map it to 0xffff_f000, regardless of
|
||||
the physical address of this page, with WIMGE=0b01010. Core 0 also enables boot
|
||||
page translation for secondary cores to use this page of memory. Then 4KB
|
||||
memory is copied from __secondary_start_page to the boot page, after flusing
|
||||
cache because this page is mapped as normal DDR. Before copying the reset page,
|
||||
core 0 puts the physical address of the spin table (which is in release.S and
|
||||
relocated to the top of mapped memory) into a variable __spin_table_addr so
|
||||
that secondary cores can see it.
|
||||
|
||||
When secondary cores boot up from 0xffff_f000 page, they only have one default
|
||||
TLB. While booting, they set up another TLB in AS=1 space and jump into
|
||||
the new space. The new TLB covers the physical address of the spin table page,
|
||||
with WIMGE =0b00100. Now secondary cores can keep polling the spin table
|
||||
without stress DDR bus because both the code and the spin table is in cache.
|
||||
|
||||
For the above to work, DDR has to set the 'M' bit of WIMGE, in order to keep
|
||||
cache coherence.
|
Loading…
Reference in a new issue