diff options
| -rw-r--r-- | arch/arm/kernel/tcm.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/arch/arm/kernel/tcm.c b/arch/arm/kernel/tcm.c index 30e302d33e0a..01ec453bb924 100644 --- a/arch/arm/kernel/tcm.c +++ b/arch/arm/kernel/tcm.c @@ -180,9 +180,9 @@ static int __init setup_tcm_bank(u8 type, u8 bank, u8 banks, */ void __init tcm_init(void) { - u32 tcm_status = read_cpuid_tcmstatus(); - u8 dtcm_banks = (tcm_status >> 16) & 0x03; - u8 itcm_banks = (tcm_status & 0x03); + u32 tcm_status; + u8 dtcm_banks; + u8 itcm_banks; size_t dtcm_code_sz = &__edtcm_data - &__sdtcm_data; size_t itcm_code_sz = &__eitcm_text - &__sitcm_text; char *start; @@ -191,6 +191,22 @@ void __init tcm_init(void) int ret; int i; + /* + * Prior to ARMv5 there is no TCM, and trying to read the status + * register will hang the processor. + */ + if (cpu_architecture() < CPU_ARCH_ARMv5) { + if (dtcm_code_sz || itcm_code_sz) + pr_info("CPU TCM: %u bytes of DTCM and %u bytes of " + "ITCM code compiled in, but no TCM present " + "in pre-v5 CPU\n", dtcm_code_sz, itcm_code_sz); + return; + } + + tcm_status = read_cpuid_tcmstatus(); + dtcm_banks = (tcm_status >> 16) & 0x03; + itcm_banks = (tcm_status & 0x03); + /* Values greater than 2 for D/ITCM banks are "reserved" */ if (dtcm_banks > 2) dtcm_banks = 0; |