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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Vineet Gupta <vgupta@synopsys.com>,
	Sasha Levin <sashal@kernel.org>,
	linux-snps-arc@lists.infradead.org
Subject: [PATCH AUTOSEL 4.14 26/33] ARCv2: support manual regfile save on interrupts
Date: Wed, 13 Mar 2019 15:14:59 -0400	[thread overview]
Message-ID: <20190313191506.159677-26-sashal@kernel.org> (raw)
In-Reply-To: <20190313191506.159677-1-sashal@kernel.org>

From: Vineet Gupta <vgupta@synopsys.com>

[ Upstream commit e494239a007e601448110ac304fe055951f9de3b ]

There's a hardware bug which affects the HSDK platform, triggered by
micro-ops for auto-saving regfile on taken interrupt. The workaround is
to inhibit autosave.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arc/Kconfig                   |  8 +++++
 arch/arc/include/asm/entry-arcv2.h | 54 ++++++++++++++++++++++++++++++
 arch/arc/kernel/entry-arcv2.S      |  4 ++-
 arch/arc/kernel/intc-arcv2.c       |  2 ++
 arch/arc/plat-hsdk/Kconfig         |  1 +
 5 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 9d06c9478a0d..82050893d0b3 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -417,6 +417,14 @@ config ARC_HAS_ACCL_REGS
 	  (also referred to as r58:r59). These can also be used by gcc as GPR so
 	  kernel needs to save/restore per process
 
+config ARC_IRQ_NO_AUTOSAVE
+	bool "Disable hardware autosave regfile on interrupts"
+	default n
+	help
+	  On HS cores, taken interrupt auto saves the regfile on stack.
+	  This is programmable and can be optionally disabled in which case
+	  software INTERRUPT_PROLOGUE/EPILGUE do the needed work
+
 endif	# ISA_ARCV2
 
 endmenu   # "ARC CPU Configuration"
diff --git a/arch/arc/include/asm/entry-arcv2.h b/arch/arc/include/asm/entry-arcv2.h
index 257a68f3c2fe..9f581553dcc3 100644
--- a/arch/arc/include/asm/entry-arcv2.h
+++ b/arch/arc/include/asm/entry-arcv2.h
@@ -17,6 +17,33 @@
 	;
 	; Now manually save: r12, sp, fp, gp, r25
 
+#ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE
+.ifnc \called_from, exception
+	st.as	r9, [sp, -10]	; save r9 in it's final stack slot
+	sub	sp, sp, 12	; skip JLI, LDI, EI
+
+	PUSH	lp_count
+	PUSHAX	lp_start
+	PUSHAX	lp_end
+	PUSH	blink
+
+	PUSH	r11
+	PUSH	r10
+
+	sub	sp, sp, 4	; skip r9
+
+	PUSH	r8
+	PUSH	r7
+	PUSH	r6
+	PUSH	r5
+	PUSH	r4
+	PUSH	r3
+	PUSH	r2
+	PUSH	r1
+	PUSH	r0
+.endif
+#endif
+
 #ifdef CONFIG_ARC_HAS_ACCL_REGS
 	PUSH	r59
 	PUSH	r58
@@ -86,6 +113,33 @@
 	POP	r59
 #endif
 
+#ifdef CONFIG_ARC_IRQ_NO_AUTOSAVE
+.ifnc \called_from, exception
+	POP	r0
+	POP	r1
+	POP	r2
+	POP	r3
+	POP	r4
+	POP	r5
+	POP	r6
+	POP	r7
+	POP	r8
+	POP	r9
+	POP	r10
+	POP	r11
+
+	POP	blink
+	POPAX	lp_end
+	POPAX	lp_start
+
+	POP	r9
+	mov	lp_count, r9
+
+	add	sp, sp, 12	; skip JLI, LDI, EI
+	ld.as	r9, [sp, -10]	; reload r9 which got clobbered
+.endif
+#endif
+
 .endm
 
 /*------------------------------------------------------------------------*/
diff --git a/arch/arc/kernel/entry-arcv2.S b/arch/arc/kernel/entry-arcv2.S
index cc558a25b8fa..562089d62d9d 100644
--- a/arch/arc/kernel/entry-arcv2.S
+++ b/arch/arc/kernel/entry-arcv2.S
@@ -209,7 +209,9 @@ restore_regs:
 ;####### Return from Intr #######
 
 debug_marker_l1:
-	bbit1.nt r0, STATUS_DE_BIT, .Lintr_ret_to_delay_slot
+	; bbit1.nt r0, STATUS_DE_BIT, .Lintr_ret_to_delay_slot
+	btst	r0, STATUS_DE_BIT		; Z flag set if bit clear
+	bnz	.Lintr_ret_to_delay_slot	; branch if STATUS_DE_BIT set
 
 .Lisr_ret_fast_path:
 	; Handle special case #1: (Entry via Exception, Return via IRQ)
diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c
index 067ea362fb3e..cf18b3e5a934 100644
--- a/arch/arc/kernel/intc-arcv2.c
+++ b/arch/arc/kernel/intc-arcv2.c
@@ -49,11 +49,13 @@ void arc_init_IRQ(void)
 
 	*(unsigned int *)&ictrl = 0;
 
+#ifndef CONFIG_ARC_IRQ_NO_AUTOSAVE
 	ictrl.save_nr_gpr_pairs = 6;	/* r0 to r11 (r12 saved manually) */
 	ictrl.save_blink = 1;
 	ictrl.save_lp_regs = 1;		/* LP_COUNT, LP_START, LP_END */
 	ictrl.save_u_to_u = 0;		/* user ctxt saved on kernel stack */
 	ictrl.save_idx_regs = 1;	/* JLI, LDI, EI */
+#endif
 
 	WRITE_AUX(AUX_IRQ_CTRL, ictrl);
 
diff --git a/arch/arc/plat-hsdk/Kconfig b/arch/arc/plat-hsdk/Kconfig
index fcc9a9e27e9c..8fb1600b29b7 100644
--- a/arch/arc/plat-hsdk/Kconfig
+++ b/arch/arc/plat-hsdk/Kconfig
@@ -9,5 +9,6 @@ menuconfig ARC_SOC_HSDK
 	bool "ARC HS Development Kit SOC"
 	depends on ISA_ARCV2
 	select ARC_HAS_ACCL_REGS
+	select ARC_IRQ_NO_AUTOSAVE
 	select CLK_HSDK
 	select RESET_HSDK
-- 
2.19.1


  parent reply	other threads:[~2019-03-13 19:16 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-13 19:14 [PATCH AUTOSEL 4.14 01/33] clk: sunxi-ng: v3s: Fix TCON reset de-assert bit Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 02/33] clk: sunxi: A31: Fix wrong AHB gate number Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 03/33] esp: Skip TX bytes accounting when sending from a request socket Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 04/33] ARM: 8824/1: fix a migrating irq bug when hotplug cpu Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 05/33] af_key: unconditionally clone on broadcast Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 06/33] assoc_array: Fix shortcut creation Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 07/33] keys: Fix dependency loop between construction record and auth key Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 08/33] scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 09/33] scsi: core: reset host byte in DID_NEXUS_FAILURE case Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 10/33] net: systemport: Fix reception of BPDUs Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 11/33] pinctrl: meson: meson8b: fix the sdxc_a data 1..3 pins Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 12/33] qmi_wwan: apply SET_DTR quirk to Sierra WP7607 Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 13/33] net: mv643xx_eth: disable clk on error path in mv643xx_eth_shared_probe() Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 14/33] mailbox: bcm-flexrm-mailbox: Fix FlexRM ring flush timeout issue Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 15/33] ASoC: topology: free created components in tplg load error Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 16/33] qed: Fix iWARP syn packet mac address validation Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 17/33] arm64: Relax GIC version check during early boot Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 18/33] net: marvell: mvneta: fix DMA debug warning Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 19/33] kasan, slub: move kasan_poison_slab hook before page_address Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 20/33] tmpfs: fix link accounting when a tmpfile is linked in Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 21/33] kasan, slab: fix conflicts with CONFIG_HARDENED_USERCOPY Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 22/33] kasan, slab: make freelist stored without tags Sasha Levin
2019-03-13 19:18   ` Andrey Konovalov
2019-03-19 19:54     ` Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 23/33] ixgbe: fix older devices that do not support IXGBE_MRQC_L3L4TXSWEN Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 24/33] ARCv2: lib: memcpy: fix doing prefetchw outside of buffer Sasha Levin
2019-03-13 19:14 ` [PATCH AUTOSEL 4.14 25/33] ARC: uacces: remove lp_start, lp_end from clobber list Sasha Levin
2019-03-13 19:14 ` Sasha Levin [this message]
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 27/33] phonet: fix building with clang Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 28/33] mac80211_hwsim: propagate genlmsg_reply return code Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 29/33] net: thunderx: make CFG_DONE message to run through generic send-ack sequence Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 30/33] nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 31/33] nfp: bpf: fix ALU32 high bits clearance bug Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 32/33] mdio_bus: Fix use-after-free on device_register fails Sasha Levin
2019-03-13 19:15 ` [PATCH AUTOSEL 4.14 33/33] net: set static variable an initial value in atl2_probe() Sasha Levin

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