diff options
| author | Nathaniel Graff | 2018-07-24 18:52:46 +0200 |
|---|---|---|
| committer | Palmer Dabbelt | 2019-06-24 08:44:41 +0200 |
| commit | b9d1848ebe8f083482307be725cca7883fca7566 (patch) | |
| tree | ec3ac603c0e2dbd7445d1ce1fd2a7d095d12f9f5 /hw/riscv | |
| parent | target/riscv: Allow setting ISA extensions via CPU props (diff) | |
| download | qemu-b9d1848ebe8f083482307be725cca7883fca7566.tar.gz qemu-b9d1848ebe8f083482307be725cca7883fca7566.tar.xz qemu-b9d1848ebe8f083482307be725cca7883fca7566.zip | |
sifive_prci: Read and write PRCI registers
Writes to the SiFive PRCI registers are preserved while leaving the
ready bits set for the HFX/HFR oscillators and the lock bit set for the
PLL.
Signed-off-by: Nathaniel Graff <nathaniel.graff@sifive.com>
Reviewed-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Diffstat (limited to 'hw/riscv')
| -rw-r--r-- | hw/riscv/sifive_prci.c | 49 |
1 files changed, 41 insertions, 8 deletions
diff --git a/hw/riscv/sifive_prci.c b/hw/riscv/sifive_prci.c index fa136b5a9f..f406682c91 100644 --- a/hw/riscv/sifive_prci.c +++ b/hw/riscv/sifive_prci.c @@ -24,15 +24,18 @@ #include "target/riscv/cpu.h" #include "hw/riscv/sifive_prci.h" -/* currently implements enough to mock freedom-e-sdk BSP clock programming */ - static uint64_t sifive_prci_read(void *opaque, hwaddr addr, unsigned int size) { - if (addr == 0 /* PRCI_HFROSCCFG */) { - return 1 << 31; /* ROSC_RDY */ - } - if (addr == 8 /* PRCI_PLLCFG */) { - return 1 << 31; /* PLL_LOCK */ + SiFivePRCIState *s = opaque; + switch (addr) { + case SIFIVE_PRCI_HFROSCCFG: + return s->hfrosccfg; + case SIFIVE_PRCI_HFXOSCCFG: + return s->hfxosccfg; + case SIFIVE_PRCI_PLLCFG: + return s->pllcfg; + case SIFIVE_PRCI_PLLOUTDIV: + return s->plloutdiv; } hw_error("%s: read: addr=0x%x\n", __func__, (int)addr); return 0; @@ -41,7 +44,30 @@ static uint64_t sifive_prci_read(void *opaque, hwaddr addr, unsigned int size) static void sifive_prci_write(void *opaque, hwaddr addr, uint64_t val64, unsigned int size) { - /* discard writes */ + SiFivePRCIState *s = opaque; + switch (addr) { + case SIFIVE_PRCI_HFROSCCFG: + s->hfrosccfg = (uint32_t) val64; + /* OSC stays ready */ + s->hfrosccfg |= SIFIVE_PRCI_HFROSCCFG_RDY; + break; + case SIFIVE_PRCI_HFXOSCCFG: + s->hfxosccfg = (uint32_t) val64; + /* OSC stays ready */ + s->hfxosccfg |= SIFIVE_PRCI_HFXOSCCFG_RDY; + break; + case SIFIVE_PRCI_PLLCFG: + s->pllcfg = (uint32_t) val64; + /* PLL stays locked */ + s->pllcfg |= SIFIVE_PRCI_PLLCFG_LOCK; + break; + case SIFIVE_PRCI_PLLOUTDIV: + s->plloutdiv = (uint32_t) val64; + break; + default: + hw_error("%s: bad write: addr=0x%x v=0x%x\n", + __func__, (int)addr, (int)val64); + } } static const MemoryRegionOps sifive_prci_ops = { @@ -61,6 +87,13 @@ static void sifive_prci_init(Object *obj) memory_region_init_io(&s->mmio, obj, &sifive_prci_ops, s, TYPE_SIFIVE_PRCI, 0x8000); sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); + + s->hfrosccfg = (SIFIVE_PRCI_HFROSCCFG_RDY | SIFIVE_PRCI_HFROSCCFG_EN); + s->hfxosccfg = (SIFIVE_PRCI_HFROSCCFG_RDY | SIFIVE_PRCI_HFROSCCFG_EN); + s->pllcfg = (SIFIVE_PRCI_PLLCFG_REFSEL | SIFIVE_PRCI_PLLCFG_BYPASS | + SIFIVE_PRCI_PLLCFG_LOCK); + s->plloutdiv = SIFIVE_PRCI_PLLOUTDIV_DIV1; + } static const TypeInfo sifive_prci_info = { |