From 3bffb6529cf10d48a97ac0d6d789986894c25c37 Mon Sep 17 00:00:00 2001 From: Dave Kleikamp Date: Mon, 8 Feb 2010 11:51:18 +0000 Subject: powerpc/booke: Add support for advanced debug registers powerpc/booke: Add support for advanced debug registers From: Dave Kleikamp Based on patches originally written by Torez Smith. This patch defines context switch and trap related functionality for BookE specific Debug Registers. It adds support to ptrace() for setting and getting BookE related Debug Registers Signed-off-by: Dave Kleikamp Cc: Torez Smith Cc: Benjamin Herrenschmidt Cc: David Gibson Cc: Josh Boyer Cc: Kumar Gala Cc: Sergio Durigan Junior Cc: Thiago Jung Bauermann Cc: linuxppc-dev list Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/traps.c | 91 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 72 insertions(+), 19 deletions(-) (limited to 'arch/powerpc/kernel/traps.c') diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 4e293b75f95..987437e04e6 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1034,9 +1034,68 @@ void SoftwareEmulation(struct pt_regs *regs) #endif /* CONFIG_8xx */ #ifdef CONFIG_PPC_ADV_DEBUG_REGS +static void handle_debug(struct pt_regs *regs, unsigned long debug_status) +{ + int changed = 0; + /* + * Determine the cause of the debug event, clear the + * event flags and send a trap to the handler. Torez + */ + if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) { + dbcr_dac(current) &= ~(DBCR_DAC1R | DBCR_DAC1W); +#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE + current->thread.dbcr2 &= ~DBCR2_DAC12MODE; +#endif + do_send_trap(regs, mfspr(SPRN_DAC1), debug_status, TRAP_HWBKPT, + 5); + changed |= 0x01; + } else if (debug_status & (DBSR_DAC2R | DBSR_DAC2W)) { + dbcr_dac(current) &= ~(DBCR_DAC2R | DBCR_DAC2W); + do_send_trap(regs, mfspr(SPRN_DAC2), debug_status, TRAP_HWBKPT, + 6); + changed |= 0x01; + } else if (debug_status & DBSR_IAC1) { + current->thread.dbcr0 &= ~DBCR0_IAC1; + dbcr_iac_range(current) &= ~DBCR_IAC12MODE; + do_send_trap(regs, mfspr(SPRN_IAC1), debug_status, TRAP_HWBKPT, + 1); + changed |= 0x01; + } else if (debug_status & DBSR_IAC2) { + current->thread.dbcr0 &= ~DBCR0_IAC2; + do_send_trap(regs, mfspr(SPRN_IAC2), debug_status, TRAP_HWBKPT, + 2); + changed |= 0x01; + } else if (debug_status & DBSR_IAC3) { + current->thread.dbcr0 &= ~DBCR0_IAC3; + dbcr_iac_range(current) &= ~DBCR_IAC34MODE; + do_send_trap(regs, mfspr(SPRN_IAC3), debug_status, TRAP_HWBKPT, + 3); + changed |= 0x01; + } else if (debug_status & DBSR_IAC4) { + current->thread.dbcr0 &= ~DBCR0_IAC4; + do_send_trap(regs, mfspr(SPRN_IAC4), debug_status, TRAP_HWBKPT, + 4); + changed |= 0x01; + } + /* + * At the point this routine was called, the MSR(DE) was turned off. + * Check all other debug flags and see if that bit needs to be turned + * back on or not. + */ + if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0, current->thread.dbcr1)) + regs->msr |= MSR_DE; + else + /* Make sure the IDM flag is off */ + current->thread.dbcr0 &= ~DBCR0_IDM; + + if (changed & 0x01) + mtspr(SPRN_DBCR0, current->thread.dbcr0); +} void __kprobes DebugException(struct pt_regs *regs, unsigned long debug_status) { + current->thread.dbsr = debug_status; + /* Hack alert: On BookE, Branch Taken stops on the branch itself, while * on server, it stops on the target of the branch. In order to simulate * the server behaviour, we thus restart right away with a single step @@ -1080,27 +1139,21 @@ void __kprobes DebugException(struct pt_regs *regs, unsigned long debug_status) if (debugger_sstep(regs)) return; - if (user_mode(regs)) - current->thread.dbcr0 &= ~(DBCR0_IC); - - _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); - } else if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) { - regs->msr &= ~MSR_DE; - if (user_mode(regs)) { - current->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W | - DBCR0_IDM); - } else { - /* Disable DAC interupts */ - mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~(DBSR_DAC1R | - DBSR_DAC1W | DBCR0_IDM)); - - /* Clear the DAC event */ - mtspr(SPRN_DBSR, (DBSR_DAC1R | DBSR_DAC1W)); + current->thread.dbcr0 &= ~DBCR0_IC; +#ifdef CONFIG_PPC_ADV_DEBUG_REGS + if (DBCR_ACTIVE_EVENTS(current->thread.dbcr0, + current->thread.dbcr1)) + regs->msr |= MSR_DE; + else + /* Make sure the IDM bit is off */ + current->thread.dbcr0 &= ~DBCR0_IDM; +#endif } - /* Setup and send the trap to the handler */ - do_dabr(regs, mfspr(SPRN_DAC1), debug_status); - } + + _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip); + } else + handle_debug(regs, debug_status); } #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ -- cgit v1.2.3