[U-Boot] [PATCH] arm64 patch: gicv3 support

bhupesh.sharma at freescale.com bhupesh.sharma at freescale.com
Wed Jan 15 15:19:02 CET 2014


Hi David,

Thanks for the patch.
Please see some comments inline:

> -----Original Message-----
> From: u-boot-bounces at lists.denx.de [mailto:u-boot-bounces at lists.denx.de]
> On Behalf Of fenghua at phytium.com.cn
> Sent: Wednesday, January 15, 2014 1:41 PM
> To: u-boot at lists.denx.de
> Cc: trini at ti.com
> Subject: [U-Boot] [PATCH] arm64 patch: gicv3 support
> 
> From: David Feng <fenghua at phytium.com.cn>
> 
> This patch add gicv3 support to uboot armv8 platform.
> Modifications cover 4 source files, as follows:
>   gic.S: gicv3 initialization and sgi interrupt raising.
>   goc.h: gicv3 register definitions.

 	^^^
Typo - gic.h

>   vexpress_aemv8a.h: add CONFIG_GICV2/CONFIG_GICV3 switch.
>   start.S: set SCR_EL3.NS bit to 1, gicv3 register of ICC_SRE_EL2
>            could be accessed only when SCR_EL3.NS=1.
>            set SCR_EL3.IRQ|FIQ|EA bits, reroute all interrupts to
>            el3 at all cores, slaves could be waken up by interrupt
>            only when the interrupt is routed to it when running
>            at el3.

Hmmm. This seems a bit suspicious - if we reroute even IRQs and Aborts
to the cores which work in EL3, they will not be visible to Linux or
Hypervisor which work in EL2 or EL1.

Have you tried to launch linux on the ARMv8 foundation model v2 with these changes?

> Note: please use the latest gcc 4.8 compiler from linaro
>       which support gicv3 system register assembling.
>

Two generic comments :

- I see in the Foundation model README that the optional GICv3 is supported
with memory-mapped CPU interface and distributor, but I see your patch accessing them
via the sytem register interface (via msr and mrs). Is this a BUG in the README?

Did you check this patch on the latest ARMv8 foundation model - v2?

- Also how about sharing the GICv2 coding between ARMv7 and ARMv8 - some of the code
may seems like a duplication from the ARMv7 GICv2 content.
 
> Signed-off-by: David Feng <fenghua at phytium.com.cn>
> ---
>  arch/arm/cpu/armv8/gic.S          |   84
> ++++++++++++++++++++++++++++++++++++-
>  arch/arm/cpu/armv8/start.S        |    5 ++-
>  arch/arm/include/asm/gic.h        |   56 +++++++++++++++++++++++++
>  include/configs/vexpress_aemv8a.h |    7 ++++
>  4 files changed, 150 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv8/gic.S b/arch/arm/cpu/armv8/gic.S index
> 599aa8f..a08939a 100644
> --- a/arch/arm/cpu/armv8/gic.S
> +++ b/arch/arm/cpu/armv8/gic.S
> @@ -23,6 +23,74 @@
>   *
> 
> *************************************************************************
> /
>  WEAK(gic_init)
> +#if defined(CONFIG_GICV3)
> +	branch_if_slave	x0, 3f
> +
> +	/* Initialize Distributor */
> +	ldr	x1, =GICD_BASE
> +	mov	w0, #0x37		/* EnableGrp0 | EnableGrp1NS */
> +					/* EnableGrp1S | ARE_S | ARE_NS */
> +	str	w0, [x1, GICD_CTLR]	/* Secure GICD_CTLR */
> +	ldr	w0, [x1, GICD_TYPER]
> +	and	w2, w0, #0x1f		/* ITLinesNumber */
> +	cbz	w2, 1f			/* No SPIs */
> +	add	x3, x1, (GICD_IGROUPRn + 4)
> +	add	x4, x1, (GICD_IGROUPMODRn + 4)
> +	mov	w5, #~0
> +0:	str	w5, [x3], #0x4
> +	str	wzr, [x4], #0x4		/* Config SPIs as Group1NS */
> +	sub	w2, w2, #0x1
> +	cbnz	w2, 0b
> +
> +	/* Initialize All ReDistributors */
> +1:	ldr	x1, =GICR_BASE
> +2:	mov	w0, #~0x2
> +	ldr	w2, [x1, GICR_WAKER]
> +	and	w2, w2, w0		/* Clear ProcessorSleep */
> +	str	w2, [x1, GICR_WAKER]
> +	dsb	st
> +	isb
> +0:	ldr	w0, [x1, GICR_WAKER]
> +	tbnz	w0, #2, 0b		/* Wait Children be Alive */
> +
> +	add	x2, x1, #(1 << 16)	/* SGI_Base */
> +	mov	w5, #~0
> +	str	w5, [x2, GICR_IGROUPRn]
> +	str	wzr, [x2, GICR_IGROUPMODRn]	/* SGIs|PPIs Group1NS */
> +	mov	w0, #0x1		/* Enable SGI 0 */
> +	str	w0, [x2, GICR_ISENABLERn]
> +
> +	ldr	w0, [x1, GICR_TYPER]
> +	add	x1, x1, #(2 << 16)
> +	tbz	w0, #4, 2b		/* Next ReDistributor if Exist */
> +
> +	/* Initialize Cpu Interface */
> +3:	mrs	x0, ICC_SRE_EL3
> +	orr	x0, x0, #0xf		/* SRE & Disable IRQ/FIQ Bypass & */
> +					/* Allow EL2 access to ICC_SRE_EL2 */
> +	msr	ICC_SRE_EL3, x0
> +	isb
> +
> +	mrs	x0, ICC_SRE_EL2
> +	orr	x0, x0, #0xf		/* SRE & Disable IRQ/FIQ Bypass & */
> +					/* Allow EL1 access to ICC_SRE_EL1 */
> +	msr	ICC_SRE_EL2, x0
> +	isb
> +
> +	mov	x0, #0x3		/* EnableGrp1NS | EnableGrp1S */
> +	msr	ICC_IGRPEN1_EL3, x0
> +	isb
> +
> +	msr	ICC_CTLR_EL3, xzr
> +	isb
> +
> +	msr	ICC_CTLR_EL1, xzr	/* NonSecure ICC_CTLR_EL1 */
> +	isb
> +
> +	mov	x0, #0x1 << 7		/* Non-Secure access to ICC_PMR_EL1
> */
> +	msr	ICC_PMR_EL1, x0
> +	isb
> +#elif defined(CONFIG_GICV2)
>  	branch_if_slave	x0, 2f
> 
>  	/* Initialize Distributor and SPIs */
> @@ -54,7 +122,7 @@ WEAK(gic_init)
> 
>  	mov	w0, #0x1 << 7		/* Non-Secure access to GICC_PMR */
>  	str	w0, [x1, GICC_PMR]
> -
> +#endif
>  	ret
>  ENDPROC(gic_init)
> 
> @@ -65,11 +133,18 @@ ENDPROC(gic_init)
>   *
> 
> *************************************************************************
> /
>  WEAK(gic_send_sgi)
> +#if defined(CONFIG_GICV3)
> +	mov	x1, #(1 << 40)
> +	orr	x1, x1, x0, lsl #24
> +	msr	ICC_ASGI1R_EL1, x1
> +	isb
> +#elif defined(CONFIG_GICV2)
>  	ldr	x1, =GICD_BASE
>  	mov	w2, #0x8000
>  	movk	w2, #0x100, lsl #16
>  	orr	w2, w2, w0
>  	str	w2, [x1, GICD_SGIR]
> +#endif
>  	ret
>  ENDPROC(gic_send_sgi)
> 
> @@ -82,11 +157,18 @@ ENDPROC(gic_send_sgi)
>   *
> 
> *************************************************************************
> /
>  WEAK(wait_for_wakeup)
> +#if defined(CONFIG_GICV3)
> +0:	wfi
> +	mrs	x0, ICC_IAR1_EL1
> +	msr	ICC_EOIR1_EL1, x0
> +	cbnz	x0, 0b
> +#elif defined(CONFIG_GICV2)
>  	ldr	x1, =GICC_BASE
>  0:	wfi
>  	ldr	w0, [x1, GICC_AIAR]
>  	str	w0, [x1, GICC_AEOIR]
>  	cbnz	w0, 0b
> +#endif
>  	ret
>  ENDPROC(wait_for_wakeup)
> 
> diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S
> index bcc2603..9911817 100644
> --- a/arch/arm/cpu/armv8/start.S
> +++ b/arch/arm/cpu/armv8/start.S
> @@ -50,7 +50,10 @@ reset:
>  	 */
>  	adr	x0, vectors
>  	switch_el x1, 3f, 2f, 1f
> -3:	msr	vbar_el3, x0
> +3:	mrs	x0, scr_el3
> +	orr	x0, x0, #0xf			/* SCR_EL3.NS|IRQ|FIQ|EA */
> +	msr	scr_el3, x0
> +	msr	vbar_el3, x0
>  	msr	cptr_el3, xzr			/* Enable FP/SIMD */
>  	ldr	x0, =COUNTER_FREQUENCY
>  	msr	cntfrq_el0, x0			/* Initialize CNTFRQ */
> diff --git a/arch/arm/include/asm/gic.h b/arch/arm/include/asm/gic.h
> index ac2b2bf..bd3a80c 100644
> --- a/arch/arm/include/asm/gic.h
> +++ b/arch/arm/include/asm/gic.h
> @@ -51,4 +51,60 @@
>  #define GICC_IIDR		0x00fc
>  #define GICC_DIR		0x1000
> 
> +/* ReDistributor Registers for Control and Physical LPIs */
> +#define GICR_CTLR		0x0000
> +#define GICR_IIDR		0x0004
> +#define GICR_TYPER		0x0008
> +#define GICR_STATUSR		0x0010
> +#define GICR_WAKER		0x0014
> +#define GICR_SETLPIR		0x0040
> +#define GICR_CLRLPIR		0x0048
> +#define GICR_SEIR		0x0068
> +#define GICR_PROPBASER		0x0070
> +#define GICR_PENDBASER		0x0078
> +#define GICR_INVLPIR		0x00a0
> +#define GICR_INVALLR		0x00b0
> +#define GICR_SYNCR		0x00c0
> +#define GICR_MOVLPIR		0x0100
> +#define GICR_MOVALLR		0x0110
> +
> +/* ReDistributor Registers for SGIs and PPIs */
> +#define GICR_IGROUPRn		0x0080
> +#define GICR_ISENABLERn		0x0100
> +#define GICR_ICENABLERn		0x0180
> +#define GICR_ISPENDRn		0x0200
> +#define GICR_ICPENDRn		0x0280
> +#define GICR_ISACTIVERn		0x0300
> +#define GICR_ICACTIVERn		0x0380
> +#define GICR_IPRIORITYRn	0x0400
> +#define GICR_ICFGR0		0x0c00
> +#define GICR_ICFGR1		0x0c04
> +#define GICR_IGROUPMODRn	0x0d00
> +#define GICR_NSACRn		0x0e00
> +
> +/* Cpu Interface System Registers */
> +#define ICC_IAR0_EL1		S3_0_C12_C8_0
> +#define ICC_IAR1_EL1		S3_0_C12_C12_0
> +#define ICC_EOIR0_EL1		S3_0_C12_C8_1
> +#define ICC_EOIR1_EL1		S3_0_C12_C12_1
> +#define ICC_HPPIR0_EL1		S3_0_C12_C8_2
> +#define ICC_HPPIR1_EL1		S3_0_C12_C12_2
> +#define ICC_BPR0_EL1		S3_0_C12_C8_3
> +#define ICC_BPR1_EL1		S3_0_C12_C12_3
> +#define ICC_DIR_EL1		S3_0_C12_C11_1
> +#define ICC_PMR_EL1		S3_0_C4_C6_0
> +#define ICC_RPR_EL1		S3_0_C12_C11_3
> +#define ICC_CTLR_EL1		S3_0_C12_C12_4
> +#define ICC_CTLR_EL3		S3_6_C12_C12_4
> +#define ICC_SRE_EL1		S3_0_C12_C12_5
> +#define ICC_SRE_EL2		S3_4_C12_C9_5
> +#define ICC_SRE_EL3		S3_6_C12_C12_5
> +#define ICC_IGRPEN0_EL1		S3_0_C12_C12_6
> +#define ICC_IGRPEN1_EL1		S3_0_C12_C12_7
> +#define ICC_IGRPEN1_EL3		S3_6_C12_C12_7
> +#define ICC_SEIEN_EL1		S3_0_C12_C13_0
> +#define ICC_SGI0R_EL1		S3_0_C12_C11_7
> +#define ICC_SGI1R_EL1		S3_0_C12_C11_5
> +#define ICC_ASGI1R_EL1		S3_0_C12_C11_6
> +
>  #endif /* __GIC_H__ */
> diff --git a/include/configs/vexpress_aemv8a.h
> b/include/configs/vexpress_aemv8a.h
> index ce5f384..ac67887 100644
> --- a/include/configs/vexpress_aemv8a.h
> +++ b/include/configs/vexpress_aemv8a.h
> @@ -12,6 +12,8 @@
> 
>  #define CONFIG_REMAKE_ELF
> 
> +#define CONFIG_GICV2
> +
>  /*#define CONFIG_ARMV8_SWITCH_TO_EL1*/
> 
>  /*#define CONFIG_SYS_GENERIC_BOARD*/
> @@ -93,8 +95,13 @@
>  #define COUNTER_FREQUENCY		(0x1800000)	/* 24MHz */
> 
>  /* Generic Interrupt Controller Definitions */
> +#ifdef CONFIG_GICV3
> +#define GICD_BASE			(0x2f000000)
> +#define GICR_BASE			(0x2f100000)
> +#else
>  #define GICD_BASE			(0x2C001000)
>  #define GICC_BASE			(0x2C002000)
> +#endif
> 
>  #define CONFIG_SYS_MEMTEST_START	V2M_BASE
>  #define CONFIG_SYS_MEMTEST_END		(V2M_BASE + 0x80000000)
> --
> 1.7.9.5
> 

Regards,
Bhupesh


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