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authorAlistair Francis <alistair.francis@wdc.com>2019-10-08 16:32:07 -0700
committerPalmer Dabbelt <palmer@sifive.com>2019-10-28 07:47:27 -0700
commita6902ef0e3a83ea3dcf54f1919d485d4cf148506 (patch)
tree364617a96147f56626c4b2f1c0e178909f6cf8d6 /hw/riscv
parent2921343b3df93e4848034ec615c01ee221212c3a (diff)
riscv/sifive_u: Add L2-LIM cache memory
On reset only a single L2 cache way is enabled, the others are exposed as memory that can be used by early boot firmware. This L2 region is generally disabled using the WayEnable register at a later stage in the boot process. To allow firmware to target QEMU and the HiFive Unleashed let's add the L2 LIM (LooselyIntegrated Memory). Ideally we would want to adjust the size of this chunk of memory as the L2 Cache Controller WayEnable register is incremented. Unfortunately I don't see a nice way to handle reducing or blocking out the L2 LIM while still allowing it be re returned to all enabled from a reset. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Diffstat (limited to 'hw/riscv')
-rw-r--r--hw/riscv/sifive_u.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 1ac51e3632..fbaa3a234e 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -65,6 +65,7 @@ static const struct MemmapEntry {
[SIFIVE_U_DEBUG] = { 0x0, 0x100 },
[SIFIVE_U_MROM] = { 0x1000, 0x11000 },
[SIFIVE_U_CLINT] = { 0x2000000, 0x10000 },
+ [SIFIVE_U_L2LIM] = { 0x8000000, 0x2000000 },
[SIFIVE_U_PLIC] = { 0xc000000, 0x4000000 },
[SIFIVE_U_PRCI] = { 0x10000000, 0x1000 },
[SIFIVE_U_UART0] = { 0x10010000, 0x1000 },
@@ -432,6 +433,7 @@ static void riscv_sifive_u_soc_realize(DeviceState *dev, Error **errp)
const struct MemmapEntry *memmap = sifive_u_memmap;
MemoryRegion *system_memory = get_system_memory();
MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
+ MemoryRegion *l2lim_mem = g_new(MemoryRegion, 1);
qemu_irq plic_gpios[SIFIVE_U_PLIC_NUM_SOURCES];
char *plic_hart_config;
size_t plic_hart_config_len;
@@ -460,6 +462,20 @@ static void riscv_sifive_u_soc_realize(DeviceState *dev, Error **errp)
memory_region_add_subregion(system_memory, memmap[SIFIVE_U_MROM].base,
mask_rom);
+ /*
+ * Add L2-LIM at reset size.
+ * This should be reduced in size as the L2 Cache Controller WayEnable
+ * register is incremented. Unfortunately I don't see a nice (or any) way
+ * to handle reducing or blocking out the L2 LIM while still allowing it
+ * be re returned to all enabled after a reset. For the time being, just
+ * leave it enabled all the time. This won't break anything, but will be
+ * too generous to misbehaving guests.
+ */
+ memory_region_init_ram(l2lim_mem, NULL, "riscv.sifive.u.l2lim",
+ memmap[SIFIVE_U_L2LIM].size, &error_fatal);
+ memory_region_add_subregion(system_memory, memmap[SIFIVE_U_L2LIM].base,
+ l2lim_mem);
+
/* create PLIC hart topology configuration string */
plic_hart_config_len = (strlen(SIFIVE_U_PLIC_HART_CONFIG) + 1) *
ms->smp.cpus;