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| author | Utkarsh Gupta <utkarsh.gupta@nxp.com> | 2016-08-31 18:41:17 -0500 |
|---|---|---|
| committer | Utkarsh Gupta <utkarsh.gupta@nxp.com> | 2016-09-01 15:57:15 -0500 |
| commit | 59dfb4293bab3dd75923ab06e68043603e3dcf4f (patch) | |
| tree | e7597f4969f879d393b2dbc7e3544e191d1c009b | |
| parent | 6f7f185664a401f03f6ce6c81b996c1f27fdbe73 (diff) | |
| download | u-boot-imx-59dfb4293bab3dd75923ab06e68043603e3dcf4f.zip u-boot-imx-59dfb4293bab3dd75923ab06e68043603e3dcf4f.tar.gz u-boot-imx-59dfb4293bab3dd75923ab06e68043603e3dcf4f.tar.bz2 | |
Disable MMU and Cache when using plugin
Signed-off-by: Utkarsh Gupta <utkarsh.gupta@nxp.com>
| -rw-r--r-- | arch/arm/include/asm/arch-mx6/mx6_plugin.S | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/arm/include/asm/arch-mx6/mx6_plugin.S b/arch/arm/include/asm/arch-mx6/mx6_plugin.S index 1560a65..ed0fb58 100644 --- a/arch/arm/include/asm/arch-mx6/mx6_plugin.S +++ b/arch/arm/include/asm/arch-mx6/mx6_plugin.S @@ -92,6 +92,34 @@ before_calling_rom___pu_irom_hwcnfg_setup: blx r4 after_calling_rom___pu_irom_hwcnfg_setup: +/* + * ROM_API_HWCNFG_SETUP function enables MMU & Caches. + * Thus disable MMU & Caches. + */ + +#define ENABLE_CACHE 0x01 + + MRC p15, 0, r0, c1, c0, 0 /* read CP15 register 1 into r0 */ + ANDS r0, r0, #0x1 /* check if MMU is enabled */ + BEQ mmu_disable_notreq /* exit if MMU is already disabled */ + +/* Disable caches, MMU */ + MRC p15, 0, r0, c1, c0, 0 /* read CP15 register 1 into r0 */ + BIC r0, r0, #(ENABLE_CACHE << 2) /* disable D Cache */ + BIC r0, r0, #0x1 /* clear bit 0 ; MMU off */ + + BIC r0, r0, #(0x1 << 11) /* disable Z, branch prediction */ + BIC r0, r0, #(0x1 << 1) /* disable A, Strict alignment */ + /* check enabled. */ + + MCR p15, 0, r0, c1, c0, 0 /* write CP15 register 1 */ + MOV r0, r0 + MOV r0, r0 + MOV r0, r0 + MOV r0, r0 + +mmu_disable_notreq: + NOP /* To return to ROM from plugin, we need to fill in these argument. * Here is what need to do: |