include: sbi_platform: Introduce HART index to HART id table

A platform can have discontinuous and/or sparse HART ids so we
cannot always assume a set of HARTs with continuous HART ids.

This patch adds support for discontinuous and sparse HART ids by
introducing HART index to HART id table. This table has platform
hart_count entries and it maps HART index to HART id.

The HART index to HART id table has only two restrictions:
1. HART index < sbi_platform hart_count
2. HART id < SBI_HARTMASK_MAX_BITS

Example1:
Let's say we have a platform with 2 HART ids 11 and 22, for such a
a platform:
hart_count = 2
hart_index2id[0] = 11
hart_index2id[1] = 22

Example2:
Let's say we have a platform with 5 HARTs ids 0, 1, 2, 3, and 4
but out of these HART with id 0 is not usable so for such a platform:
hart_count = 5
hart_index2id[0] = -1U
hart_index2id[1] = 1
hart_index2id[2] = 2
hart_index2id[3] = 3
hart_index2id[4] = 4
OR
hart_count = 4
hart_index2id[0] = 1
hart_index2id[1] = 2
hart_index2id[2] = 3
hart_index2id[3] = 4

With HART index to HART id table in place, the hart_disabled()
callback is now redundant so we remove it as well.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This commit is contained in:
Anup Patel
2020-03-15 11:39:25 +05:30
committed by Anup Patel
parent 75eec9dd3f
commit c51f02cf14
6 changed files with 89 additions and 28 deletions

View File

@@ -351,6 +351,7 @@ _start_warm:
csrw CSR_MIE, zero
csrw CSR_MIP, zero
/* Find HART count and HART stack size */
la a4, platform
#if __riscv_xlen == 64
lwu s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
@@ -359,12 +360,29 @@ _start_warm:
lw s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
lw s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
#endif
REG_L s9, SBI_PLATFORM_HART_INDEX2ID_OFFSET(a4)
/* HART ID should be within expected limit */
/* Find HART id */
csrr s6, CSR_MHARTID
bge s6, s7, _start_hang
/* find the scratch space for this hart */
/* Find HART index */
beqz s9, 3f
li a4, 0
1:
#if __riscv_xlen == 64
lwu a5, (s9)
#else
lw a5, (s9)
#endif
beq a5, s6, 2f
add s9, s9, 4
add a4, a4, 1
blt a4, s7, 1b
li a4, -1
2: add s6, a4, zero
3: bge s6, s7, _start_hang
/* Find the scratch space based on HART index */
la tp, _fw_end
mul a5, s7, s8
add tp, tp, a5
@@ -411,6 +429,7 @@ _link_end:
_hartid_to_scratch:
/*
* a0 -> HART ID (passed by caller)
* a1 -> HART Index (passed by caller)
* t0 -> HART Stack Size
* t1 -> HART Stack End
* t2 -> Temporary
@@ -423,7 +442,7 @@ _hartid_to_scratch:
lw t0, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(t2)
lw t2, SBI_PLATFORM_HART_COUNT_OFFSET(t2)
#endif
sub t2, t2, a0
sub t2, t2, a1
mul t2, t2, t0
la t1, _fw_end
add t1, t1, t2