From 77451997237fa7e8ba4f5e2f0fcd99898f78ff9b Mon Sep 17 00:00:00 2001 From: Matt Redfearn Date: Wed, 7 Sep 2016 10:45:18 +0100 Subject: [PATCH] MIPS: pm-cps: Support CM3 changes to Coherence Enable Register MIPS CM3 changed the management of coherence. Instead of a coherence control register with a bitmask of coherent domains, CM3 simply has a coherence enable register with a single bit to enable coherence of the local core. Support this by clearing and setting this single bit to disable / enable coherence. Signed-off-by: Matt Redfearn Reviewed-by: Paul Burton Cc: Adam Buchbinder Cc: Tony Wu Cc: Masahiro Yamada Cc: Nikolay Martynov Cc: Kees Cook Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14226/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mips-cm.h | 1 + arch/mips/kernel/pm-cps.c | 31 ++++++++++++++++++------------- 2 files changed, 19 insertions(+), 13 deletions(-) diff --git a/arch/mips/include/asm/mips-cm.h b/arch/mips/include/asm/mips-cm.h index 4fafeefe65c2..2e4180797b21 100644 --- a/arch/mips/include/asm/mips-cm.h +++ b/arch/mips/include/asm/mips-cm.h @@ -359,6 +359,7 @@ BUILD_CM_Cx_R_(tcid_8_priority, 0x80) /* GCR_Cx_COHERENCE register fields */ #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_SHF 0 #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK (_ULCAST_(0xff) << 0) +#define CM3_GCR_Cx_COHERENCE_COHEN_MSK (_ULCAST_(0x1) << 0) /* GCR_Cx_CONFIG register fields */ #define CM_GCR_Cx_CONFIG_IOCUTYPE_SHF 10 diff --git a/arch/mips/kernel/pm-cps.c b/arch/mips/kernel/pm-cps.c index 440e79259566..05bcdedcf9bd 100644 --- a/arch/mips/kernel/pm-cps.c +++ b/arch/mips/kernel/pm-cps.c @@ -480,18 +480,20 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) uasm_i_sync(&p, STYPE_SYNC); uasm_i_ehb(&p); - /* - * Disable all but self interventions. The load from COHCTL is defined - * by the interAptiv & proAptiv SUMs as ensuring that the operation - * resulting from the preceding store is complete. - */ - uasm_i_addiu(&p, t0, zero, 1 << cpu_data[cpu].core); - uasm_i_sw(&p, t0, 0, r_pcohctl); - uasm_i_lw(&p, t0, 0, r_pcohctl); - - /* Barrier to ensure write to coherence control is complete */ - uasm_i_sync(&p, STYPE_SYNC); - uasm_i_ehb(&p); + if (mips_cm_revision() < CM_REV_CM3) { + /* + * Disable all but self interventions. The load from COHCTL is + * defined by the interAptiv & proAptiv SUMs as ensuring that the + * operation resulting from the preceding store is complete. + */ + uasm_i_addiu(&p, t0, zero, 1 << cpu_data[cpu].core); + uasm_i_sw(&p, t0, 0, r_pcohctl); + uasm_i_lw(&p, t0, 0, r_pcohctl); + + /* Barrier to ensure write to coherence control is complete */ + uasm_i_sync(&p, STYPE_SYNC); + uasm_i_ehb(&p); + } /* Disable coherence */ uasm_i_sw(&p, zero, 0, r_pcohctl); @@ -566,7 +568,10 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) * will run this. The first will actually re-enable coherence & the * rest will just be performing a rather unusual nop. */ - uasm_i_addiu(&p, t0, zero, CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK); + uasm_i_addiu(&p, t0, zero, mips_cm_revision() < CM_REV_CM3 + ? CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK + : CM3_GCR_Cx_COHERENCE_COHEN_MSK); + uasm_i_sw(&p, t0, 0, r_pcohctl); uasm_i_lw(&p, t0, 0, r_pcohctl); -- 2.20.1