[PATCH 2/2] RISC-V: KVM: Use IMSIC guest files when available

From: Anup Patel
Date: Thu Apr 11 2024 - 05:07:34 EST


Let us discover and use IMSIC guest files from the IMSIC global
config provided by the IMSIC irqchip driver.

Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
arch/riscv/kvm/aia.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)

diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
index 8ea51a791371..596209f1a6ff 100644
--- a/arch/riscv/kvm/aia.c
+++ b/arch/riscv/kvm/aia.c
@@ -394,6 +394,8 @@ int kvm_riscv_aia_alloc_hgei(int cpu, struct kvm_vcpu *owner,
{
int ret = -ENOENT;
unsigned long flags;
+ const struct imsic_global_config *gc;
+ const struct imsic_local_config *lc;
struct aia_hgei_control *hgctrl = per_cpu_ptr(&aia_hgei, cpu);

if (!kvm_riscv_aia_available() || !hgctrl)
@@ -409,11 +411,14 @@ int kvm_riscv_aia_alloc_hgei(int cpu, struct kvm_vcpu *owner,

raw_spin_unlock_irqrestore(&hgctrl->lock, flags);

- /* TODO: To be updated later by AIA IMSIC HW guest file support */
- if (hgei_va)
- *hgei_va = NULL;
- if (hgei_pa)
- *hgei_pa = 0;
+ gc = imsic_get_global_config();
+ lc = (gc) ? per_cpu_ptr(gc->local, cpu) : NULL;
+ if (lc && ret > 0) {
+ if (hgei_va)
+ *hgei_va = lc->msi_va + (ret * IMSIC_MMIO_PAGE_SZ);
+ if (hgei_pa)
+ *hgei_pa = lc->msi_pa + (ret * IMSIC_MMIO_PAGE_SZ);
+ }

return ret;
}
@@ -600,9 +605,11 @@ void kvm_riscv_aia_disable(void)
int kvm_riscv_aia_init(void)
{
int rc;
+ const struct imsic_global_config *gc;

if (!riscv_isa_extension_available(NULL, SxAIA))
return -ENODEV;
+ gc = imsic_get_global_config();

/* Figure-out number of bits in HGEIE */
csr_write(CSR_HGEIE, -1UL);
@@ -614,17 +621,17 @@ int kvm_riscv_aia_init(void)
/*
* Number of usable HGEI lines should be minimum of per-HART
* IMSIC guest files and number of bits in HGEIE
- *
- * TODO: To be updated later by AIA IMSIC HW guest file support
*/
- kvm_riscv_aia_nr_hgei = 0;
+ if (gc)
+ kvm_riscv_aia_nr_hgei = min((ulong)kvm_riscv_aia_nr_hgei,
+ BIT(gc->guest_index_bits) - 1);
+ else
+ kvm_riscv_aia_nr_hgei = 0;

- /*
- * Find number of guest MSI IDs
- *
- * TODO: To be updated later by AIA IMSIC HW guest file support
- */
+ /* Find number of guest MSI IDs */
kvm_riscv_aia_max_ids = IMSIC_MAX_ID;
+ if (gc && kvm_riscv_aia_nr_hgei)
+ kvm_riscv_aia_max_ids = gc->nr_guest_ids + 1;

/* Initialize guest external interrupt line management */
rc = aia_hgei_init();
--
2.34.1