LoongArch: KVM: Add different length support in loongarch_pch_pic_read()

With function loongarch_pch_pic_read(), currently it is hardcoded length
for different registers, and the length comes from exising linux pch_pic
driver code. But in theory, all length 1/2/4/8 should be supported for
all the registers, here add different length support about register read
emulation in function loongarch_pch_pic_read().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
index c19cf9d7b08a1494b49c22145394acc32f96a789..be63901ab7aba45bae568996ab8283d7897f15be 100644 (file)
--- a/arch/loongarch/kvm/intc/pch_pic.c
+++ b/arch/loongarch/kvm/intc/pch_pic.c
@@ -118,55 +118,45 @@ static u32 pch_pic_write_reg(u64 *s, int high, u32 v)
 
 static int loongarch_pch_pic_read(struct loongarch_pch_pic *s, gpa_t addr, int len, void *val)
 {
-       int offset, index, ret = 0;
-       u32 data = 0;
+       int ret = 0, offset;
+       u64 data = 0;
+       void *ptemp;
 
        offset = addr - s->pch_pic_base;
+       offset -= offset & 7;
 
        spin_lock(&s->lock);
        switch (offset) {
        case PCH_PIC_INT_ID_START ... PCH_PIC_INT_ID_END:
-               *(u64 *)val = s->id.data;
+               data = s->id.data;
                break;
        case PCH_PIC_MASK_START ... PCH_PIC_MASK_END:
-               offset -= PCH_PIC_MASK_START;
-               index = offset >> 2;
-               /* read mask reg */
-               data = pch_pic_read_reg(&s->mask, index);
-               *(u32 *)val = data;
+               data = s->mask;
                break;
        case PCH_PIC_HTMSI_EN_START ... PCH_PIC_HTMSI_EN_END:
-               offset -= PCH_PIC_HTMSI_EN_START;
-               index = offset >> 2;
                /* read htmsi enable reg */
-               data = pch_pic_read_reg(&s->htmsi_en, index);
-               *(u32 *)val = data;
+               data = s->htmsi_en;
                break;
        case PCH_PIC_EDGE_START ... PCH_PIC_EDGE_END:
-               offset -= PCH_PIC_EDGE_START;
-               index = offset >> 2;
                /* read edge enable reg */
-               data = pch_pic_read_reg(&s->edge, index);
-               *(u32 *)val = data;
+               data = s->edge;
                break;
        case PCH_PIC_AUTO_CTRL0_START ... PCH_PIC_AUTO_CTRL0_END:
        case PCH_PIC_AUTO_CTRL1_START ... PCH_PIC_AUTO_CTRL1_END:
                /* we only use default mode: fixed interrupt distribution mode */
-               *(u32 *)val = 0;
                break;
        case PCH_PIC_ROUTE_ENTRY_START ... PCH_PIC_ROUTE_ENTRY_END:
                /* only route to int0: eiointc */
-               *(u8 *)val = 1;
+               ptemp = s->route_entry + (offset - PCH_PIC_ROUTE_ENTRY_START);
+               data = *(u64 *)ptemp;
                break;
        case PCH_PIC_HTMSI_VEC_START ... PCH_PIC_HTMSI_VEC_END:
-               offset -= PCH_PIC_HTMSI_VEC_START;
                /* read htmsi vector */
-               data = s->htmsi_vector[offset];
-               *(u8 *)val = data;
+               ptemp = s->htmsi_vector + (offset - PCH_PIC_HTMSI_VEC_START);
+               data = *(u64 *)ptemp;
                break;
        case PCH_PIC_POLARITY_START ... PCH_PIC_POLARITY_END:
-               /* we only use defalut value 0: high level triggered */
-               *(u32 *)val = 0;
+               data = s->polarity;
                break;
        case PCH_PIC_INT_IRR_START:
                data = s->irr;
@@ -179,6 +169,12 @@ static int loongarch_pch_pic_read(struct loongarch_pch_pic *s, gpa_t addr, int l
        }
        spin_unlock(&s->lock);
 
+       if (ret == 0) {
+               offset = (addr - s->pch_pic_base) & 7;
+               data = data >> (offset * 8);
+               memcpy(val, &data, len);
+       }
+
        return ret;
 }