From 5e94c6e33e7c4726ef09f46c267e9ca232c5148a Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar Date: Sun, 9 Jan 2011 02:59:09 +0530 Subject: ARM: OMAP4: PM: Add L2X0 cache lowpower support When MPUSS hits off-mode, L2 cache is lost. This patch adds L2X0 necessary maintenance operations and context restoration in the low power code. Signed-off-by: Santosh Shilimkar Acked-by: Jean Pihet Reviewed-by: Kevin Hilman Tested-by: Vishwanath BS Signed-off-by: Kevin Hilman --- arch/arm/mach-omap2/sleep44xx.S | 95 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) (limited to 'arch/arm/mach-omap2/sleep44xx.S') diff --git a/arch/arm/mach-omap2/sleep44xx.S b/arch/arm/mach-omap2/sleep44xx.S index e5521945ba8e..3154b63def35 100644 --- a/arch/arm/mach-omap2/sleep44xx.S +++ b/arch/arm/mach-omap2/sleep44xx.S @@ -32,6 +32,9 @@ ppa_zero_params: .word 0x0 +ppa_por_params: + .word 1, 0 + /* * ============================= * == CPU suspend finisher == @@ -132,6 +135,54 @@ skip_scu_gp_set: mcrne p15, 0, r0, c1, c0, 1 isb dsb +#ifdef CONFIG_CACHE_L2X0 + /* + * Clean and invalidate the L2 cache. + * Common cache-l2x0.c functions can't be used here since it + * uses spinlocks. We are out of coherency here with data cache + * disabled. The spinlock implementation uses exclusive load/store + * instruction which can fail without data cache being enabled. + * OMAP4 hardware doesn't support exclusive monitor which can + * overcome exclusive access issue. Because of this, CPU can + * lead to deadlock. + */ + bl omap4_get_sar_ram_base + mov r8, r0 + mrc p15, 0, r5, c0, c0, 5 @ Read MPIDR + ands r5, r5, #0x0f + ldreq r0, [r8, #L2X0_SAVE_OFFSET0] @ Retrieve L2 state from SAR + ldrne r0, [r8, #L2X0_SAVE_OFFSET1] @ memory. + cmp r0, #3 + bne do_WFI +#ifdef CONFIG_PL310_ERRATA_727915 + mov r0, #0x03 + mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX + DO_SMC +#endif + bl omap4_get_l2cache_base + mov r2, r0 + ldr r0, =0xffff + str r0, [r2, #L2X0_CLEAN_INV_WAY] +wait: + ldr r0, [r2, #L2X0_CLEAN_INV_WAY] + ldr r1, =0xffff + ands r0, r0, r1 + bne wait +#ifdef CONFIG_PL310_ERRATA_727915 + mov r0, #0x00 + mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX + DO_SMC +#endif +l2x_sync: + bl omap4_get_l2cache_base + mov r2, r0 + mov r0, #0x0 + str r0, [r2, #L2X0_CACHE_SYNC] +sync: + ldr r0, [r2, #L2X0_CACHE_SYNC] + ands r0, r0, #0x1 + bne sync +#endif do_WFI: bl omap_do_wfi @@ -225,6 +276,50 @@ enable_smp_bit: mcreq p15, 0, r0, c1, c0, 1 isb skip_ns_smp_enable: +#ifdef CONFIG_CACHE_L2X0 + /* + * Restore the L2 AUXCTRL and enable the L2 cache. + * OMAP4_MON_L2X0_AUXCTRL_INDEX = Program the L2X0 AUXCTRL + * OMAP4_MON_L2X0_CTRL_INDEX = Enable the L2 using L2X0 CTRL + * register r0 contains value to be programmed. + * L2 cache is already invalidate by ROM code as part + * of MPUSS OFF wakeup path. + */ + ldr r2, =OMAP44XX_L2CACHE_BASE + ldr r0, [r2, #L2X0_CTRL] + and r0, #0x0f + cmp r0, #1 + beq skip_l2en @ Skip if already enabled + ldr r3, =OMAP44XX_SAR_RAM_BASE + ldr r1, [r3, #OMAP_TYPE_OFFSET] + cmp r1, #0x1 @ Check for HS device + bne set_gp_por + ldr r0, =OMAP4_PPA_L2_POR_INDEX + ldr r1, =OMAP44XX_SAR_RAM_BASE + ldr r4, [r1, #L2X0_PREFETCH_CTRL_OFFSET] + adr r3, ppa_por_params + str r4, [r3, #0x04] + mov r1, #0x0 @ Process ID + mov r2, #0x4 @ Flag + mov r6, #0xff + mov r12, #0x00 @ Secure Service ID + DO_SMC + b set_aux_ctrl +set_gp_por: + ldr r1, =OMAP44XX_SAR_RAM_BASE + ldr r0, [r1, #L2X0_PREFETCH_CTRL_OFFSET] + ldr r12, =OMAP4_MON_L2X0_PREFETCH_INDEX @ Setup L2 PREFETCH + DO_SMC +set_aux_ctrl: + ldr r1, =OMAP44XX_SAR_RAM_BASE + ldr r0, [r1, #L2X0_AUXCTRL_OFFSET] + ldr r12, =OMAP4_MON_L2X0_AUXCTRL_INDEX @ Setup L2 AUXCTRL + DO_SMC + mov r0, #0x1 + ldr r12, =OMAP4_MON_L2X0_CTRL_INDEX @ Enable L2 cache + DO_SMC +skip_l2en: +#endif b cpu_resume @ Jump to generic resume ENDPROC(omap4_cpu_resume) -- cgit v1.2.1