From a3ea14df0e383f44dcb2e61badb71180dbffe526 Mon Sep 17 00:00:00 2001 From: Paul Fox Date: Tue, 26 Jul 2011 16:42:26 +0100 Subject: [PATCH 1/3] x86, olpc: Wait for last byte of EC command to be accepted When executing EC commands, only waiting when there are still more bytes to write is usually fine. However, if the system suspends very quickly after a call to olpc_ec_cmd(), the last data byte may not yet be transferred to the EC, and the command will not complete. This solves a bug where the SCI wakeup mask was not correctly written when going into suspend. It means that sometimes, on XO-1.5 (but not XO-1), the devices that were marked as wakeup sources can't wake up the system. e.g. you ask for wifi wakeups, suspend, but then incoming wifi frames don't wake up the system as they should. Signed-off-by: Paul Fox Signed-off-by: Daniel Drake Acked-by: Andres Salomon Cc: Signed-off-by: Ingo Molnar --- arch/x86/platform/olpc/olpc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c index 8b9940e78e2f..7cce722667b8 100644 --- a/arch/x86/platform/olpc/olpc.c +++ b/arch/x86/platform/olpc/olpc.c @@ -161,13 +161,13 @@ restart: if (inbuf && inlen) { /* write data to EC */ for (i = 0; i < inlen; i++) { + pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]); + outb(inbuf[i], 0x68); if (wait_on_ibf(0x6c, 0)) { printk(KERN_ERR "olpc-ec: timeout waiting for" " EC accept data!\n"); goto err; } - pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]); - outb(inbuf[i], 0x68); } } if (outbuf && outlen) { From 05e33fc20ea5e493a2a1e7f1d04f43cdf89f83ed Mon Sep 17 00:00:00 2001 From: Jack Steiner Date: Fri, 5 Aug 2011 09:09:00 -0500 Subject: [PATCH 2/3] x86, UV: Remove UV delay in starting slave cpus Delete the 10 msec delay between the INIT and SIPI when starting slave cpus. I can find no requirement for this delay. BIOS also has similar code sequences without the delay. Removing the delay reduces boot time by 40 sec. Every bit helps. Signed-off-by: Jack Steiner Cc: Link: http://lkml.kernel.org/r/20110805140900.GA6774@sgi.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/apic/x2apic_uv_x.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index adc66c3a1fef..34b18594e724 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -207,7 +207,6 @@ static int __cpuinit uv_wakeup_secondary(int phys_apicid, unsigned long start_ri ((start_rip << UVH_IPI_INT_VECTOR_SHFT) >> 12) | APIC_DM_INIT; uv_write_global_mmr64(pnode, UVH_IPI_INT, val); - mdelay(10); val = (1UL << UVH_IPI_INT_SEND_SHFT) | (phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) | From 7ca0758cdb7c241cb4e0490a8d95f0eb5b861daf Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 22 Aug 2011 13:27:06 -0700 Subject: [PATCH 3/3] x86-32, vdso: On system call restart after SYSENTER, use int $0x80 When we enter a 32-bit system call via SYSENTER or SYSCALL, we shuffle the arguments to match the int $0x80 calling convention. This was probably a design mistake, but it's what it is now. This causes errors if the system call as to be restarted. For SYSENTER, we have to invoke the instruction from the vdso as the return address is hardcoded. Accordingly, we can simply replace the jump in the vdso with an int $0x80 instruction and use the slower entry point for a post-restart. Suggested-by: Linus Torvalds Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/r/CA%2B55aFztZ=r5wa0x26KJQxvZOaQq8s2v3u50wCyJcA-Sc4g8gQ@mail.gmail.com Cc: --- arch/x86/vdso/vdso32/sysenter.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/vdso/vdso32/sysenter.S b/arch/x86/vdso/vdso32/sysenter.S index e2800affa754..e354bceee0e0 100644 --- a/arch/x86/vdso/vdso32/sysenter.S +++ b/arch/x86/vdso/vdso32/sysenter.S @@ -43,7 +43,7 @@ __kernel_vsyscall: .space 7,0x90 /* 14: System call restart point is here! (SYSENTER_RETURN-2) */ - jmp .Lenter_kernel + int $0x80 /* 16: System call normal return point is here! */ VDSO32_SYSENTER_RETURN: /* Symbol used by sysenter.c via vdso32-syms.h */ pop %ebp