hw/misc/aspeed_hace: Add support for source, digest, key buffer 64 bit addresses

According to the AST2700 design, the data source address is 64-bit, with
R_HASH_SRC_HI storing bits [63:32] and R_HASH_SRC storing bits [31:0].
Similarly, the digest address is 64-bit, with R_HASH_DIGEST_HI storing bits
[63:32] and R_HASH_DIGEST storing bits [31:0]. The HMAC key buffer address is also
64-bit, with R_HASH_KEY_BUFF_HI storing bits [63:32] and R_HASH_KEY_BUFF storing
bits [31:0].

The AST2700 supports a maximum DRAM size of 8 GB, with a DRAM addressable range
from 0x0_0000_0000 to 0x1_FFFF_FFFF. Since this range fits within 34 bits, only
bits [33:0] are needed to store the DRAM offset. To optimize address storage,
the high physical address bits [1:0] of the source, digest and key buffer
addresses are stored as dram_offset bits [33:32].

To achieve this, a src_hi_mask with a mask value of 0x3 is introduced, ensuring
that src_addr_hi consists of bits [1:0]. The final src_addr is computed as
(src_addr_hi[1:0] << 32) | src_addr[31:0], representing the DRAM offset within
bits [33:0].

Similarly, a dest_hi_mask with a mask value of 0x3 is introduced to ensure that
dest_addr_hi consists of bits [1:0]. The final dest_addr is calculated as
(dest_addr_hi[1:0] << 32) | dest_addr[31:0], representing the DRAM offset within
bits [33:0].

Additionally, a key_hi_mask with a mask value of 0x3 is introduced to ensure
that key_buf_addr_hi consists of bits [1:0]. The final key_buf_addr is
determined as (key_buf_addr_hi[1:0] << 32) | key_buf_addr[31:0], representing
the DRAM offset within bits [33:0].

This approach eliminates the need to reduce the high part of the DRAM physical
address for DMA operations. Previously, this was calculated as
(high physical address bits [7:0] - 4), since the DRAM start address is
0x4_00000000, making the high part address [7:0] - 4.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250515081008.583578-14-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

include/hw/misc/aspeed_hace.h

@@ -50,6 +50,9 @@ struct AspeedHACEClass {
     uint32_t hash_mask;
     uint64_t nr_regs;
     bool raise_crypt_interrupt_workaround;
+    uint32_t src_hi_mask;
+    uint32_t dest_hi_mask;
+    uint32_t key_hi_mask;
 };
 
 #endif /* ASPEED_HACE_H */