On 9/25/20 12:17 PM, Luc Michel wrote:
> The cprman PLLs generate a clock based on a prescaler, a multiplier and
> a divider. The prescaler doubles the parent (xosc) frequency, then the
> multiplier/divider are applied. The multiplier has an integer and a
> fractionnal part.
Typo "fractional".
>
> This commit also implements the cprman CM_LOCK register. This register
> reports which PLL is currently locked. We consider a PLL has being
> locked as soon as it is enabled (on real hardware, there is a delay
> after turning a PLL on, for it to stabilise).
Typo "stabilize".
>
> Signed-off-by: Luc Michel <l...@lmichel.fr>
> ---
> include/hw/misc/bcm2835_cprman_internals.h | 8 +++
> hw/misc/bcm2835_cprman.c | 64 +++++++++++++++++++++-
> 2 files changed, 71 insertions(+), 1 deletion(-)
>
> diff --git a/include/hw/misc/bcm2835_cprman_internals.h
> b/include/hw/misc/bcm2835_cprman_internals.h
> index 5cfa849492..22a2500ab0 100644
> --- a/include/hw/misc/bcm2835_cprman_internals.h
> +++ b/include/hw/misc/bcm2835_cprman_internals.h
> @@ -98,10 +98,18 @@ REG32(A2W_PLLA_FRAC, 0x1200)
> REG32(A2W_PLLC_FRAC, 0x1220)
> REG32(A2W_PLLD_FRAC, 0x1240)
> REG32(A2W_PLLH_FRAC, 0x1260)
> REG32(A2W_PLLB_FRAC, 0x12e0)
>
> +/* misc registers */
> +REG32(CM_LOCK, 0x114)
> + FIELD(CM_LOCK, FLOCKH, 12, 1)
> + FIELD(CM_LOCK, FLOCKD, 11, 1)
> + FIELD(CM_LOCK, FLOCKC, 10, 1)
> + FIELD(CM_LOCK, FLOCKB, 9, 1)
> + FIELD(CM_LOCK, FLOCKA, 8, 1)
> +
> /*
> * This field is common to all registers. Each register write value must
> match
> * the CPRMAN_PASSWORD magic value in its 8 MSB.
> */
> FIELD(CPRMAN, PASSWORD, 24, 8)
> diff --git a/hw/misc/bcm2835_cprman.c b/hw/misc/bcm2835_cprman.c
> index ad71d30a86..ba82522eb1 100644
> --- a/hw/misc/bcm2835_cprman.c
> +++ b/hw/misc/bcm2835_cprman.c
> @@ -48,13 +48,51 @@
> #include "hw/misc/bcm2835_cprman_internals.h"
> #include "trace.h"
>
> /* PLL */
>
> +static bool pll_is_locked(const CprmanPLLState *pll)
> +{
> + return !FIELD_EX32(*pll->reg_a2w_ctrl, A2W_PLLx_CTRL, PWRDN)
> + && !FIELD_EX32(*pll->reg_cm, CM_PLLx, ANARST);
> +}
> +
> static void pll_update(CprmanPLLState *pll)
> {
> - clock_update(pll->out, 0);
> + uint64_t freq, ndiv, fdiv, pdiv;
> +
> + if (!pll_is_locked(pll)) {
> + clock_update(pll->out, 0);
> + return;
> + }
> +
> + pdiv = FIELD_EX32(*pll->reg_a2w_ctrl, A2W_PLLx_CTRL, PDIV);
> +
> + if (!pdiv) {
> + clock_update(pll->out, 0);
> + return;
> + }
> +
> + ndiv = FIELD_EX32(*pll->reg_a2w_ctrl, A2W_PLLx_CTRL, NDIV);
> + fdiv = FIELD_EX32(*pll->reg_a2w_frac, A2W_PLLx_FRAC, FRAC);
> +
> + if (pll->reg_a2w_ana[1] & pll->prediv_mask) {
> + /* The prescaler doubles the parent frequency */
> + ndiv *= 2;
> + fdiv *= 2;
> + }
> +
> + /*
> + * We have a multiplier with an integer part (ndiv) and a fractional part
> + * (fdiv), and a divider (pdiv).
> + */
> + freq = clock_get_hz(pll->xosc_in) *
> + ((ndiv << R_A2W_PLLx_FRAC_FRAC_LENGTH) + fdiv);
> + freq /= pdiv;
> + freq >>= R_A2W_PLLx_FRAC_FRAC_LENGTH;
Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> +
> + clock_update_hz(pll->out, freq);
> }
>
> static void pll_xosc_update(void *opaque)
> {
> pll_update(CPRMAN_PLL(opaque));
> @@ -94,18 +132,42 @@ static const TypeInfo cprman_pll_info = {
> };
>
>
> /* CPRMAN "top level" model */
>
> +static uint32_t get_cm_lock(const BCM2835CprmanState *s)
> +{
> + static const int CM_LOCK_MAPPING[] = {
Maybe CM_LOCK_MAPPING[CPRMAN_NUM_PLL].
> + [CPRMAN_PLLA] = R_CM_LOCK_FLOCKA_SHIFT,
> + [CPRMAN_PLLC] = R_CM_LOCK_FLOCKC_SHIFT,
> + [CPRMAN_PLLD] = R_CM_LOCK_FLOCKD_SHIFT,
> + [CPRMAN_PLLH] = R_CM_LOCK_FLOCKH_SHIFT,
> + [CPRMAN_PLLB] = R_CM_LOCK_FLOCKB_SHIFT,
> + };
> +
> + uint32_t r = 0;
> + size_t i;
> +
> + for (i = 0; i < CPRMAN_NUM_PLL; i++) {
> + r |= pll_is_locked(&s->plls[i]) << CM_LOCK_MAPPING[i];
> + }
> +
> + return r;
> +}
> +
> static uint64_t cprman_read(void *opaque, hwaddr offset,
> unsigned size)
> {
> BCM2835CprmanState *s = CPRMAN(opaque);
> uint64_t r = 0;
> size_t idx = offset / sizeof(uint32_t);
>
> switch (idx) {
> + case R_CM_LOCK:
> + r = get_cm_lock(s);
> + break;
> +
> default:
> r = s->regs[idx];
> }
>
> trace_bcm2835_cprman_read(offset, r);
>
