[v2,1/2] firmware: Use lla to access all global symbols

When OpenSBI is compiled as fPIE mode, the assembler will translate "la"
to GOT reference pattern. It will cause to cost an additional load
instruction when obtaining the symbol address. However, if the symbol
locates within the positive or negative 2GB region, we can use "lla"
instead of "la" to avoid unneeded GOT references. This patch assumes that
the OpenSBI image excluding the payload does not exceed 2GB. Based on
this assumption, all "la" instructions are replaced by "lla" to avoid
performance degradation when compiling as fPIE mode.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
---
 firmware/fw_base.S            | 88 +++++++++++++++++++++----------------------
 firmware/fw_dynamic.S         | 18 ++++-----
 firmware/fw_jump.S            |  2 +-
 firmware/fw_payload.S         |  2 +-
 firmware/payloads/test_head.S | 18 ++++-----
 5 files changed, 64 insertions(+), 64 deletions(-)

> -----Original Message-----
> From: opensbi <opensbi-bounces@lists.infradead.org> On Behalf Of Vincent
> Chen
> Sent: 05 March 2021 14:34
> To: opensbi@lists.infradead.org
> Cc: Vincent Chen <vincent.chen@sifive.com>
> Subject: [PATCH v2 1/2] firmware: Use lla to access all global symbols
> 
> When OpenSBI is compiled as fPIE mode, the assembler will translate "la"
> to GOT reference pattern. It will cause to cost an additional load instruction
> when obtaining the symbol address. However, if the symbol locates within
> the positive or negative 2GB region, we can use "lla"
> instead of "la" to avoid unneeded GOT references. This patch assumes that
> the OpenSBI image excluding the payload does not exceed 2GB. Based on
> this assumption, all "la" instructions are replaced by "lla" to avoid
> performance degradation when compiling as fPIE mode.
> 
> Signed-off-by: Vincent Chen <vincent.chen@sifive.com>

Looks good to me.

Reviewed-by: Anup Patel <anup.patel@wdc.com>

Regards,
Anup

> ---
>  firmware/fw_base.S            | 88 +++++++++++++++++++++----------------------
>  firmware/fw_dynamic.S         | 18 ++++-----
>  firmware/fw_jump.S            |  2 +-
>  firmware/fw_payload.S         |  2 +-
>  firmware/payloads/test_head.S | 18 ++++-----
>  5 files changed, 64 insertions(+), 64 deletions(-)
> 
> diff --git a/firmware/fw_base.S b/firmware/fw_base.S index
> ab33e11..6cc5f88 100644
> --- a/firmware/fw_base.S
> +++ b/firmware/fw_base.S
> @@ -57,39 +57,39 @@ _start:
>  	bne	a0, a6, _wait_relocate_copy_done
>  _try_lottery:
>  	/* Jump to relocation wait loop if we don't get relocation lottery */
> -	la	a6, _relocate_lottery
> +	lla	a6, _relocate_lottery
>  	li	a7, 1
>  	amoadd.w a6, a7, (a6)
>  	bnez	a6, _wait_relocate_copy_done
> 
>  	/* Save load address */
> -	la	t0, _load_start
> -	la	t1, _start
> +	lla	t0, _load_start
> +	lla	t1, _start
>  	REG_S	t1, 0(t0)
> 
>  	/* Relocate if load address != link address */
>  _relocate:
> -	la	t0, _link_start
> +	lla	t0, _link_start
>  	REG_L	t0, 0(t0)
> -	la	t1, _link_end
> +	lla	t1, _link_end
>  	REG_L	t1, 0(t1)
> -	la	t2, _load_start
> +	lla	t2, _load_start
>  	REG_L	t2, 0(t2)
>  	sub	t3, t1, t0
>  	add	t3, t3, t2
>  	beq	t0, t2, _relocate_done
> -	la	t4, _relocate_done
> +	lla	t4, _relocate_done
>  	sub	t4, t4, t2
>  	add	t4, t4, t0
>  	blt	t2, t0, _relocate_copy_to_upper
>  _relocate_copy_to_lower:
>  	ble	t1, t2, _relocate_copy_to_lower_loop
> -	la	t3, _relocate_lottery
> +	lla	t3, _relocate_lottery
>  	BRANGE	t2, t1, t3, _start_hang
> -	la	t3, _boot_status
> +	lla	t3, _boot_status
>  	BRANGE	t2, t1, t3, _start_hang
> -	la	t3, _relocate
> -	la	t5, _relocate_done
> +	lla	t3, _relocate
> +	lla	t5, _relocate_done
>  	BRANGE	t2, t1, t3, _start_hang
>  	BRANGE	t2, t1, t5, _start_hang
>  	BRANGE  t3, t5, t2, _start_hang
> @@ -102,12 +102,12 @@ _relocate_copy_to_lower_loop:
>  	jr	t4
>  _relocate_copy_to_upper:
>  	ble	t3, t0, _relocate_copy_to_upper_loop
> -	la	t2, _relocate_lottery
> +	lla	t2, _relocate_lottery
>  	BRANGE	t0, t3, t2, _start_hang
> -	la	t2, _boot_status
> +	lla	t2, _boot_status
>  	BRANGE	t0, t3, t2, _start_hang
> -	la	t2, _relocate
> -	la	t5, _relocate_done
> +	lla	t2, _relocate
> +	lla	t5, _relocate_done
>  	BRANGE	t0, t3, t2, _start_hang
>  	BRANGE	t0, t3, t5, _start_hang
>  	BRANGE	t2, t5, t0, _start_hang
> @@ -119,12 +119,12 @@ _relocate_copy_to_upper_loop:
>  	blt	t0, t1, _relocate_copy_to_upper_loop
>  	jr	t4
>  _wait_relocate_copy_done:
> -	la	t0, _start
> -	la	t1, _link_start
> +	lla	t0, _start
> +	lla	t1, _link_start
>  	REG_L	t1, 0(t1)
>  	beq	t0, t1, _wait_for_boot_hart
> -	la	t2, _boot_status
> -	la	t3, _wait_for_boot_hart
> +	lla	t2, _boot_status
> +	lla	t3, _wait_for_boot_hart
>  	sub	t3, t3, t0
>  	add	t3, t3, t1
>  1:
> @@ -143,10 +143,10 @@ _relocate_done:
>  	 * Mark relocate copy done
>  	 * Use _boot_status copy relative to the load address
>  	 */
> -	la	t0, _boot_status
> -	la	t1, _link_start
> +	lla	t0, _boot_status
> +	lla	t1, _link_start
>  	REG_L	t1, 0(t1)
> -	la	t2, _load_start
> +	lla	t2, _load_start
>  	REG_L	t2, 0(t2)
>  	sub	t0, t0, t1
>  	add	t0, t0, t2
> @@ -161,19 +161,19 @@ _relocate_done:
>  	call	_reset_regs
> 
>  	/* Zero-out BSS */
> -	la	s4, _bss_start
> -	la	s5, _bss_end
> +	lla	s4, _bss_start
> +	lla	s5, _bss_end
>  _bss_zero:
>  	REG_S	zero, (s4)
>  	add	s4, s4, __SIZEOF_POINTER__
>  	blt	s4, s5, _bss_zero
> 
>  	/* Setup temporary trap handler */
> -	la	s4, _start_hang
> +	lla	s4, _start_hang
>  	csrw	CSR_MTVEC, s4
> 
>  	/* Setup temporary stack */
> -	la	s4, _fw_end
> +	lla	s4, _fw_end
>  	li	s5, (SBI_SCRATCH_SIZE * 2)
>  	add	sp, s4, s5
> 
> @@ -184,7 +184,7 @@ _bss_zero:
> 
>  #ifdef FW_FDT_PATH
>  	/* Override previous arg1 */
> -	la	a1, fw_fdt_bin
> +	lla	a1, fw_fdt_bin
>  #endif
> 
>  	/*
> @@ -202,7 +202,7 @@ _bss_zero:
>  	 * s7 -> HART Count
>  	 * s8 -> HART Stack Size
>  	 */
> -	la	a4, platform
> +	lla	a4, platform
>  #if __riscv_xlen == 64
>  	lwu	s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
>  	lwu	s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
> @@ -212,7 +212,7 @@ _bss_zero:
>  #endif
> 
>  	/* Setup scratch space for all the HARTs*/
> -	la	tp, _fw_end
> +	lla	tp, _fw_end
>  	mul	a5, s7, s8
>  	add	tp, tp, a5
>  	/* Keep a copy of tp */
> @@ -230,8 +230,8 @@ _scratch_init:
> 
>  	/* Initialize scratch space */
>  	/* Store fw_start and fw_size in scratch space */
> -	la	a4, _fw_start
> -	la	a5, _fw_end
> +	lla	a4, _fw_start
> +	lla	a5, _fw_end
>  	mul	t0, s7, s8
>  	add	a5, a5, t0
>  	sub	a5, a5, a4
> @@ -253,16 +253,16 @@ _scratch_init:
>  	REG_S	a0, SBI_SCRATCH_NEXT_MODE_OFFSET(tp)
>  	MOV_3R	a0, s0, a1, s1, a2, s2
>  	/* Store warm_boot address in scratch space */
> -	la	a4, _start_warm
> +	lla	a4, _start_warm
>  	REG_S	a4, SBI_SCRATCH_WARMBOOT_ADDR_OFFSET(tp)
>  	/* Store platform address in scratch space */
> -	la	a4, platform
> +	lla	a4, platform
>  	REG_S	a4, SBI_SCRATCH_PLATFORM_ADDR_OFFSET(tp)
>  	/* Store hartid-to-scratch function address in scratch space */
> -	la	a4, _hartid_to_scratch
> +	lla	a4, _hartid_to_scratch
>  	REG_S	a4, SBI_SCRATCH_HARTID_TO_SCRATCH_OFFSET(tp)
>  	/* Store trap-exit function address in scratch space */
> -	la	a4, _trap_exit
> +	lla	a4, _trap_exit
>  	REG_S	a4, SBI_SCRATCH_TRAP_EXIT_OFFSET(tp)
>  	/* Clear tmp0 in scratch space */
>  	REG_S	zero, SBI_SCRATCH_TMP0_OFFSET(tp)
> @@ -343,7 +343,7 @@ _fdt_reloc_done:
> 
>  	/* mark boot hart done */
>  	li	t0, BOOT_STATUS_BOOT_HART_DONE
> -	la	t1, _boot_status
> +	lla	t1, _boot_status
>  	REG_S	t0, 0(t1)
>  	fence	rw, rw
>  	j	_start_warm
> @@ -351,7 +351,7 @@ _fdt_reloc_done:
>  	/* waiting for boot hart to be done (_boot_status == 2) */
>  _wait_for_boot_hart:
>  	li	t0, BOOT_STATUS_BOOT_HART_DONE
> -	la	t1, _boot_status
> +	lla	t1, _boot_status
>  	REG_L	t1, 0(t1)
>  	/* Reduce the bus traffic so that boot hart may proceed faster */
>  	nop
> @@ -369,7 +369,7 @@ _start_warm:
>  	csrw	CSR_MIP, zero
> 
>  	/* Find HART count and HART stack size */
> -	la	a4, platform
> +	lla	a4, platform
>  #if __riscv_xlen == 64
>  	lwu	s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
>  	lwu	s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
> @@ -400,7 +400,7 @@ _start_warm:
>  3:	bge	s6, s7, _start_hang
> 
>  	/* Find the scratch space based on HART index */
> -	la	tp, _fw_end
> +	lla	tp, _fw_end
>  	mul	a5, s7, s8
>  	add	tp, tp, a5
>  	mul	a5, s8, s6
> @@ -415,13 +415,13 @@ _start_warm:
>  	add	sp, tp, zero
> 
>  	/* Setup trap handler */
> -	la	a4, _trap_handler
> +	lla	a4, _trap_handler
>  #if __riscv_xlen == 32
>  	csrr	a5, CSR_MISA
>  	srli	a5, a5, ('H' - 'A')
>  	andi	a5, a5, 0x1
>  	beq	a5, zero, _skip_trap_handler_rv32_hyp
> -	la	a4, _trap_handler_rv32_hyp
> +	lla	a4, _trap_handler_rv32_hyp
>  _skip_trap_handler_rv32_hyp:
>  #endif
>  	csrw	CSR_MTVEC, a4
> @@ -432,7 +432,7 @@ _skip_trap_handler_rv32_hyp:
>  	srli	a5, a5, ('H' - 'A')
>  	andi	a5, a5, 0x1
>  	beq	a5, zero, _skip_trap_exit_rv32_hyp
> -	la	a4, _trap_exit_rv32_hyp
> +	lla	a4, _trap_exit_rv32_hyp
>  	csrr	a5, CSR_MSCRATCH
>  	REG_S	a4, SBI_SCRATCH_TRAP_EXIT_OFFSET(a5)
>  _skip_trap_exit_rv32_hyp:
> @@ -468,7 +468,7 @@ _hartid_to_scratch:
>  	 * t1 -> HART Stack End
>  	 * t2 -> Temporary
>  	 */
> -	la	t2, platform
> +	lla	t2, platform
>  #if __riscv_xlen == 64
>  	lwu	t0, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(t2)
>  	lwu	t2, SBI_PLATFORM_HART_COUNT_OFFSET(t2)
> @@ -478,7 +478,7 @@ _hartid_to_scratch:
>  #endif
>  	sub	t2, t2, a1
>  	mul	t2, t2, t0
> -	la	t1, _fw_end
> +	lla	t1, _fw_end
>  	add	t1, t1, t2
>  	li	t2, SBI_SCRATCH_SIZE
>  	sub	a0, t1, t2
> diff --git a/firmware/fw_dynamic.S b/firmware/fw_dynamic.S index
> 8b56947..0705e63 100644
> --- a/firmware/fw_dynamic.S
> +++ b/firmware/fw_dynamic.S
> @@ -54,7 +54,7 @@ fw_boot_hart:
>  	 */
>  fw_save_info:
>  	/* Save next arg1 in 'a1' */
> -	la	a4, _dynamic_next_arg1
> +	lla	a4, _dynamic_next_arg1
>  	REG_S	a1, (a4)
> 
>  	/* Sanity checks */
> @@ -66,13 +66,13 @@ fw_save_info:
>  	bgt	a3, a4, _bad_dynamic_info
> 
>  	/* Save version == 0x1 fields */
> -	la	a4, _dynamic_next_addr
> +	lla	a4, _dynamic_next_addr
>  	REG_L	a3, FW_DYNAMIC_INFO_NEXT_ADDR_OFFSET(a2)
>  	REG_S	a3, (a4)
> -	la	a4, _dynamic_next_mode
> +	lla	a4, _dynamic_next_mode
>  	REG_L	a3, FW_DYNAMIC_INFO_NEXT_MODE_OFFSET(a2)
>  	REG_S	a3, (a4)
> -	la	a4, _dynamic_options
> +	lla	a4, _dynamic_options
>  	REG_L	a3, FW_DYNAMIC_INFO_OPTIONS_OFFSET(a2)
>  	REG_S	a3, (a4)
> 
> @@ -80,7 +80,7 @@ fw_save_info:
>  	li	a4, 0x2
>  	REG_L	a3, FW_DYNAMIC_INFO_VERSION_OFFSET(a2)
>  	blt	a3, a4, 2f
> -	la	a4, _dynamic_boot_hart
> +	lla	a4, _dynamic_boot_hart
>  	REG_L	a3, FW_DYNAMIC_INFO_BOOT_HART_OFFSET(a2)
>  	REG_S	a3, (a4)
>  2:
> @@ -96,7 +96,7 @@ fw_save_info:
>  	 * The next arg1 should be returned in 'a0'.
>  	 */
>  fw_next_arg1:
> -	la	a0, _dynamic_next_arg1
> +	lla	a0, _dynamic_next_arg1
>  	REG_L	a0, (a0)
>  	ret
> 
> @@ -108,7 +108,7 @@ fw_next_arg1:
>  	 * The next address should be returned in 'a0'.
>  	 */
>  fw_next_addr:
> -	la	a0, _dynamic_next_addr
> +	lla	a0, _dynamic_next_addr
>  	REG_L	a0, (a0)
>  	ret
> 
> @@ -120,7 +120,7 @@ fw_next_addr:
>  	 * The next address should be returned in 'a0'
>  	 */
>  fw_next_mode:
> -	la	a0, _dynamic_next_mode
> +	lla	a0, _dynamic_next_mode
>  	REG_L	a0, (a0)
>  	ret
> 
> @@ -133,7 +133,7 @@ fw_next_mode:
>  	 * The next address should be returned in 'a0'.
>  	 */
>  fw_options:
> -	la	a0, _dynamic_options
> +	lla	a0, _dynamic_options
>  	REG_L	a0, (a0)
>  	ret
> 
> diff --git a/firmware/fw_jump.S b/firmware/fw_jump.S index
> 8553f8c..5b24f8b 100644
> --- a/firmware/fw_jump.S
> +++ b/firmware/fw_jump.S
> @@ -59,7 +59,7 @@ fw_next_arg1:
>  	 * The next address should be returned in 'a0'.
>  	 */
>  fw_next_addr:
> -	la	a0, _jump_addr
> +	lla	a0, _jump_addr
>  	REG_L	a0, (a0)
>  	ret
> 
> diff --git a/firmware/fw_payload.S b/firmware/fw_payload.S index
> 1ef121e..c53a3bb 100644
> --- a/firmware/fw_payload.S
> +++ b/firmware/fw_payload.S
> @@ -59,7 +59,7 @@ fw_next_arg1:
>  	 * The next address should be returned in 'a0'.
>  	 */
>  fw_next_addr:
> -	la	a0, payload_bin
> +	lla	a0, payload_bin
>  	ret
> 
>  	.section .entry, "ax", %progbits
> diff --git a/firmware/payloads/test_head.S
> b/firmware/payloads/test_head.S index 840013e..4852f71 100644
> --- a/firmware/payloads/test_head.S
> +++ b/firmware/payloads/test_head.S
> @@ -28,20 +28,20 @@
>  	.globl _start
>  _start:
>  	/* Pick one hart to run the main boot sequence */
> -	la	a3, _hart_lottery
> +	lla	a3, _hart_lottery
>  	li	a2, 1
>  	amoadd.w a3, a2, (a3)
>  	bnez	a3, _start_hang
> 
>  	/* Save a0 and a1 */
> -	la	a3, _boot_a0
> +	lla	a3, _boot_a0
>  	REG_S	a0, 0(a3)
> -	la	a3, _boot_a1
> +	lla	a3, _boot_a1
>  	REG_S	a1, 0(a3)
> 
>  	/* Zero-out BSS */
> -	la	a4, _bss_start
> -	la	a5, _bss_end
> +	lla	a4, _bss_start
> +	lla	a5, _bss_end
>  _bss_zero:
>  	REG_S	zero, (a4)
>  	add	a4, a4, __SIZEOF_POINTER__
> @@ -53,18 +53,18 @@ _start_warm:
>  	csrw	CSR_SIP, zero
> 
>  	/* Setup exception vectors */
> -	la	a3, _start_hang
> +	lla	a3, _start_hang
>  	csrw	CSR_STVEC, a3
> 
>  	/* Setup stack */
> -	la	a3, _payload_end
> +	lla	a3, _payload_end
>  	li	a4, 0x2000
>  	add	sp, a3, a4
> 
>  	/* Jump to C main */
> -	la	a3, _boot_a0
> +	lla	a3, _boot_a0
>  	REG_L	a0, 0(a3)
> -	la	a3, _boot_a1
> +	lla	a3, _boot_a1
>  	REG_L	a1, 0(a3)
>  	call	test_main
> 
> --
> 2.7.4
> 
> 
> --
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