| Andrew Geissler | 9347dd4 | 2023-03-03 12:38:41 -0600 | [diff] [blame^] | 1 | From 9da48e3433b919868650cd60e28827273a42c63b Mon Sep 17 00:00:00 2001 |
| Brad Bishop | bec4ebc | 2022-08-03 09:55:16 -0400 | [diff] [blame] | 2 | From: Jaxson Han <jaxson.han@arm.com> |
| 3 | Date: Tue, 25 Jan 2022 14:56:36 +0800 |
| 4 | Subject: [PATCH] PSCI: Add function call entry point |
| 5 | |
| 6 | The max exception level of Armv8R AArch64 is EL2, which means it has no |
| 7 | exclusive EL for firmware. That is, firmware and hypervisors have to share |
| 8 | the EL2. Also, hypervisors cannot call firmware services via a 'smc' |
| 9 | instruction. Thus, boot-wrapper has to provide a function entry point |
| 10 | for Armv8R AArch64. |
| 11 | |
| 12 | Issue-Id: SCM-3816 |
| 13 | Upstream-Status: Inappropriate [other] |
| 14 | Implementation pending further discussion |
| 15 | Signed-off-by: Jaxson Han <jaxson.han@arm.com> |
| 16 | Change-Id: I06ec8e50298603155c6d8ae2330e71db2f111182 |
| 17 | --- |
| 18 | common/psci.c | 24 ++++++++++++++++++++---- |
| 19 | 1 file changed, 20 insertions(+), 4 deletions(-) |
| 20 | |
| 21 | diff --git a/common/psci.c b/common/psci.c |
| 22 | index 6efc695..8fdefb5 100644 |
| 23 | --- a/common/psci.c |
| 24 | +++ b/common/psci.c |
| 25 | @@ -20,6 +20,8 @@ |
| 26 | |
| 27 | extern unsigned int spsr_to_elx; |
| 28 | |
| 29 | +unsigned long flag_from_smc_fn[NR_CPUS]; |
| 30 | + |
| 31 | static unsigned long branch_table[NR_CPUS]; |
| 32 | |
| 33 | bakery_ticket_t branch_table_lock[NR_CPUS]; |
| 34 | @@ -49,12 +51,14 @@ static int psci_cpu_on(unsigned long target_mpidr, unsigned long address) |
| 35 | return PSCI_RET_INVALID_PARAMETERS; |
| 36 | |
| 37 | bakery_lock(branch_table_lock, this_cpu); |
| 38 | - ret = psci_store_address(cpu, address); |
| 39 | - bakery_unlock(branch_table_lock, this_cpu); |
| 40 | - |
| 41 | #ifdef KEEP_EL |
| 42 | - spsr_to_elx = SPSR_KERNEL_EL1; |
| 43 | + if (!flag_from_smc_fn[this_cpu]) { |
| 44 | + spsr_to_elx = SPSR_KERNEL_EL1; |
| 45 | + flush_per_cpu_data((void*)&(spsr_to_elx)); |
| 46 | + } |
| 47 | #endif |
| 48 | + ret = psci_store_address(cpu, address); |
| 49 | + bakery_unlock(branch_table_lock, this_cpu); |
| 50 | |
| 51 | return ret; |
| 52 | } |
| 53 | @@ -90,6 +94,18 @@ long psci_call(unsigned long fid, unsigned long arg1, unsigned long arg2) |
| 54 | } |
| 55 | } |
| 56 | |
| 57 | +long smc_fn_entry(unsigned long fid, unsigned long arg1, unsigned long arg2) |
| 58 | +{ |
| 59 | + long ret; |
| 60 | + unsigned int this_cpu = this_cpu_logical_id(); |
| 61 | + |
| 62 | + flag_from_smc_fn[this_cpu] = 1; |
| 63 | + ret = psci_call(fid, arg1, arg2); |
| 64 | + flag_from_smc_fn[this_cpu] = 0; |
| 65 | + |
| 66 | + return ret; |
| 67 | +} |
| 68 | + |
| 69 | void __noreturn psci_first_spin(unsigned int cpu) |
| 70 | { |
| 71 | if (cpu == MPIDR_INVALID) |