diff options
Diffstat (limited to 'bsp/meta-synopsys/recipes-kernel/linux/linux-arc/8000-ARCv2-support-manual-regfile-save-on-interrupts.patch')
| -rw-r--r-- | bsp/meta-synopsys/recipes-kernel/linux/linux-arc/8000-ARCv2-support-manual-regfile-save-on-interrupts.patch | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/bsp/meta-synopsys/recipes-kernel/linux/linux-arc/8000-ARCv2-support-manual-regfile-save-on-interrupts.patch b/bsp/meta-synopsys/recipes-kernel/linux/linux-arc/8000-ARCv2-support-manual-regfile-save-on-interrupts.patch new file mode 100644 index 00000000..79c65725 --- /dev/null +++ b/bsp/meta-synopsys/recipes-kernel/linux/linux-arc/8000-ARCv2-support-manual-regfile-save-on-interrupts.patch @@ -0,0 +1,157 @@ +From 7e9246a982a6ae6a2b19f3d3f1a437a6417577fb Mon Sep 17 00:00:00 2001 +From: Vineet Gupta <vgupta@synopsys.com> +Date: Wed, 6 Jun 2018 10:20:37 -0700 +Subject: [PATCH] ARCv2: support manual regfile save on interrupts + +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> +--- + 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 376366a7db81..7215f52b3413 100644 +--- a/arch/arc/Kconfig ++++ b/arch/arc/Kconfig +@@ -407,6 +407,14 @@ 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 309f4e6721b3..225e7df2d8ed 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 f25c085b9874..23e00216e5a5 100644 +--- a/arch/arc/plat-hsdk/Kconfig ++++ b/arch/arc/plat-hsdk/Kconfig +@@ -9,6 +9,7 @@ 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 + select HAVE_PCI +-- +2.16.2 + |