diff mbox series

[v2,13/15] hw/misc/bcm2835_cprman: add sane reset values to the registers

Message ID 20201005195612.1999165-14-luc@lmichel.fr
State New
Headers show
Series raspi: add the bcm2835 cprman clock manager | expand

Commit Message

Luc Michel Oct. 5, 2020, 7:56 p.m. UTC 
Those reset values have been extracted from a Raspberry Pi 3 model B
v1.2, using the 2020-08-20 version of raspios. The dump was done using
the debugfs interface of the CPRMAN driver in Linux (under
'/sys/kernel/debug/clk'). Each exposed clock tree stage (PLLs, channels
and muxes) can be observed by reading the 'regdump' file (e.g.
'plla/regdump').

Those values are set by the Raspberry Pi firmware at boot time (Linux
expects them to be set when it boots up).

Some stages are not exposed by the Linux driver (e.g. the PLL B). For
those, the reset values are unknown and left to 0 which implies a
disabled output.

Once booted in QEMU, the final clock tree is very similar to the one
visible on real hardware. The differences come from some unimplemented
devices for which the driver simply disable the corresponding clock.

Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Luc Michel <luc@lmichel.fr>
---
 include/hw/misc/bcm2835_cprman_internals.h | 269 +++++++++++++++++++++
 hw/misc/bcm2835_cprman.c                   |  31 +++
 2 files changed, 300 insertions(+)

Comments

Philippe Mathieu-Daudé Oct. 19, 2020, 3:39 p.m. UTC | #1 
On 10/5/20 9:56 PM, Luc Michel wrote:
> Those reset values have been extracted from a Raspberry Pi 3 model B
> v1.2, using the 2020-08-20 version of raspios. The dump was done using
> the debugfs interface of the CPRMAN driver in Linux (under
> '/sys/kernel/debug/clk'). Each exposed clock tree stage (PLLs, channels
> and muxes) can be observed by reading the 'regdump' file (e.g.
> 'plla/regdump').
> 
> Those values are set by the Raspberry Pi firmware at boot time (Linux
> expects them to be set when it boots up).
> 
> Some stages are not exposed by the Linux driver (e.g. the PLL B). For
> those, the reset values are unknown and left to 0 which implies a
> disabled output.
> 
> Once booted in QEMU, the final clock tree is very similar to the one
> visible on real hardware. The differences come from some unimplemented
> devices for which the driver simply disable the corresponding clock.
> 
> Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Luc Michel <luc@lmichel.fr>
> ---
>   include/hw/misc/bcm2835_cprman_internals.h | 269 +++++++++++++++++++++
>   hw/misc/bcm2835_cprman.c                   |  31 +++
>   2 files changed, 300 insertions(+)

I haven't verified the dumped values with real hardware,
but for the rest this patch shouldn't introduce regression,
and it helps to boot up to Linux kernel 5.7, so:

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff mbox series

Patch

diff --git a/include/hw/misc/bcm2835_cprman_internals.h b/include/hw/misc/bcm2835_cprman_internals.h
index d9abda91cb..8361c4c423 100644
--- a/include/hw/misc/bcm2835_cprman_internals.h
+++ b/include/hw/misc/bcm2835_cprman_internals.h
@@ -744,6 +744,275 @@  static inline void set_clock_mux_init_info(BCM2835CprmanState *s,
     mux->reg_cm = &s->regs[CLOCK_MUX_INIT_INFO[id].cm_offset];
     mux->int_bits = CLOCK_MUX_INIT_INFO[id].int_bits;
     mux->frac_bits = CLOCK_MUX_INIT_INFO[id].frac_bits;
 }
 
+
+/*
+ * Object reset info
+ * Those values have been dumped from a Raspberry Pi 3 Model B v1.2 using the
+ * clk debugfs interface in Linux.
+ */
+typedef struct PLLResetInfo {
+    uint32_t cm;
+    uint32_t a2w_ctrl;
+    uint32_t a2w_ana[4];
+    uint32_t a2w_frac;
+} PLLResetInfo;
+
+static const PLLResetInfo PLL_RESET_INFO[] = {
+    [CPRMAN_PLLA] = {
+        .cm = 0x0000008a,
+        .a2w_ctrl = 0x0002103a,
+        .a2w_frac = 0x00098000,
+        .a2w_ana = { 0x00000000, 0x00144000, 0x00000000, 0x00000100 }
+    },
+
+    [CPRMAN_PLLC] = {
+        .cm = 0x00000228,
+        .a2w_ctrl = 0x0002103e,
+        .a2w_frac = 0x00080000,
+        .a2w_ana = { 0x00000000, 0x00144000, 0x00000000, 0x00000100 }
+    },
+
+    [CPRMAN_PLLD] = {
+        .cm = 0x0000020a,
+        .a2w_ctrl = 0x00021034,
+        .a2w_frac = 0x00015556,
+        .a2w_ana = { 0x00000000, 0x00144000, 0x00000000, 0x00000100 }
+    },
+
+    [CPRMAN_PLLH] = {
+        .cm = 0x00000000,
+        .a2w_ctrl = 0x0002102d,
+        .a2w_frac = 0x00000000,
+        .a2w_ana = { 0x00900000, 0x0000000c, 0x00000000, 0x00000000 }
+    },
+
+    [CPRMAN_PLLB] = {
+        /* unknown */
+        .cm = 0x00000000,
+        .a2w_ctrl = 0x00000000,
+        .a2w_frac = 0x00000000,
+        .a2w_ana = { 0x00000000, 0x00000000, 0x00000000, 0x00000000 }
+    }
+};
+
+typedef struct PLLChannelResetInfo {
+    /*
+     * Even though a PLL channel has a CM register, it shares it with its
+     * parent PLL. The parent already takes care of the reset value.
+     */
+    uint32_t a2w_ctrl;
+} PLLChannelResetInfo;
+
+static const PLLChannelResetInfo PLL_CHANNEL_RESET_INFO[] = {
+    [CPRMAN_PLLA_CHANNEL_DSI0] = { .a2w_ctrl = 0x00000100 },
+    [CPRMAN_PLLA_CHANNEL_CORE] = { .a2w_ctrl = 0x00000003 },
+    [CPRMAN_PLLA_CHANNEL_PER] = { .a2w_ctrl = 0x00000000 }, /* unknown */
+    [CPRMAN_PLLA_CHANNEL_CCP2] = { .a2w_ctrl = 0x00000100 },
+
+    [CPRMAN_PLLC_CHANNEL_CORE2] = { .a2w_ctrl = 0x00000100 },
+    [CPRMAN_PLLC_CHANNEL_CORE1] = { .a2w_ctrl = 0x00000100 },
+    [CPRMAN_PLLC_CHANNEL_PER] = { .a2w_ctrl = 0x00000002 },
+    [CPRMAN_PLLC_CHANNEL_CORE0] = { .a2w_ctrl = 0x00000002 },
+
+    [CPRMAN_PLLD_CHANNEL_DSI0] = { .a2w_ctrl = 0x00000100 },
+    [CPRMAN_PLLD_CHANNEL_CORE] = { .a2w_ctrl = 0x00000004 },
+    [CPRMAN_PLLD_CHANNEL_PER] = { .a2w_ctrl = 0x00000004 },
+    [CPRMAN_PLLD_CHANNEL_DSI1] = { .a2w_ctrl = 0x00000100 },
+
+    [CPRMAN_PLLH_CHANNEL_AUX] = { .a2w_ctrl = 0x00000004 },
+    [CPRMAN_PLLH_CHANNEL_RCAL] = { .a2w_ctrl = 0x00000000 },
+    [CPRMAN_PLLH_CHANNEL_PIX] = { .a2w_ctrl = 0x00000000 },
+
+    [CPRMAN_PLLB_CHANNEL_ARM] = { .a2w_ctrl = 0x00000000 }, /* unknown */
+};
+
+typedef struct ClockMuxResetInfo {
+    uint32_t cm_ctrl;
+    uint32_t cm_div;
+} ClockMuxResetInfo;
+
+static const ClockMuxResetInfo CLOCK_MUX_RESET_INFO[] = {
+    [CPRMAN_CLOCK_GNRIC] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_VPU] = {
+        .cm_ctrl = 0x00000245,
+        .cm_div = 0x00003000,
+    },
+
+    [CPRMAN_CLOCK_SYS] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_PERIA] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_PERII] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_H264] = {
+        .cm_ctrl = 0x00000244,
+        .cm_div = 0x00003000,
+    },
+
+    [CPRMAN_CLOCK_ISP] = {
+        .cm_ctrl = 0x00000244,
+        .cm_div = 0x00003000,
+    },
+
+    [CPRMAN_CLOCK_V3D] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_CAM0] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_CAM1] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_CCP2] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_DSI0E] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_DSI0P] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_DPI] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_GP0] = {
+        .cm_ctrl = 0x00000200,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_GP1] = {
+        .cm_ctrl = 0x00000096,
+        .cm_div = 0x00014000,
+    },
+
+    [CPRMAN_CLOCK_GP2] = {
+        .cm_ctrl = 0x00000291,
+        .cm_div = 0x00249f00,
+    },
+
+    [CPRMAN_CLOCK_HSM] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_OTP] = {
+        .cm_ctrl = 0x00000091,
+        .cm_div = 0x00004000,
+    },
+
+    [CPRMAN_CLOCK_PCM] = {
+        .cm_ctrl = 0x00000200,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_PWM] = {
+        .cm_ctrl = 0x00000200,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_SLIM] = {
+        .cm_ctrl = 0x00000200,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_SMI] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_TEC] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_TD0] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_TD1] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_TSENS] = {
+        .cm_ctrl = 0x00000091,
+        .cm_div = 0x0000a000,
+    },
+
+    [CPRMAN_CLOCK_TIMER] = {
+        .cm_ctrl = 0x00000291,
+        .cm_div = 0x00013333,
+    },
+
+    [CPRMAN_CLOCK_UART] = {
+        .cm_ctrl = 0x00000296,
+        .cm_div = 0x0000a6ab,
+    },
+
+    [CPRMAN_CLOCK_VEC] = {
+        .cm_ctrl = 0x00000097,
+        .cm_div = 0x00002000,
+    },
+
+    [CPRMAN_CLOCK_PULSE] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_SDC] = {
+        .cm_ctrl = 0x00004006,
+        .cm_div = 0x00003000,
+    },
+
+    [CPRMAN_CLOCK_ARM] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+
+    [CPRMAN_CLOCK_AVEO] = {
+        .cm_ctrl = 0x00000000,
+        .cm_div = 0x00000000,
+    },
+
+    [CPRMAN_CLOCK_EMMC] = {
+        .cm_ctrl = 0x00000295,
+        .cm_div = 0x00006000,
+    },
+
+    [CPRMAN_CLOCK_EMMC2] = {
+        .cm_ctrl = 0, /* unknown */
+        .cm_div = 0
+    },
+};
+
 #endif
diff --git a/hw/misc/bcm2835_cprman.c b/hw/misc/bcm2835_cprman.c
index 4f5bb7a182..4ede5a52a0 100644
--- a/hw/misc/bcm2835_cprman.c
+++ b/hw/misc/bcm2835_cprman.c
@@ -51,10 +51,21 @@ 
 #include "hw/misc/bcm2835_cprman_internals.h"
 #include "trace.h"
 
 /* PLL */
 
+static void pll_reset(DeviceState *dev)
+{
+    CprmanPllState *s = CPRMAN_PLL(dev);
+    const PLLResetInfo *info = &PLL_RESET_INFO[s->id];
+
+    *s->reg_cm = info->cm;
+    *s->reg_a2w_ctrl = info->a2w_ctrl;
+    memcpy(s->reg_a2w_ana, info->a2w_ana, sizeof(info->a2w_ana));
+    *s->reg_a2w_frac = info->a2w_frac;
+}
+
 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);
 }
@@ -121,10 +132,11 @@  static const VMStateDescription pll_vmstate = {
 
 static void pll_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
+    dc->reset = pll_reset;
     dc->vmsd = &pll_vmstate;
 }
 
 static const TypeInfo cprman_pll_info = {
     .name = TYPE_CPRMAN_PLL,
@@ -135,10 +147,18 @@  static const TypeInfo cprman_pll_info = {
 };
 
 
 /* PLL channel */
 
+static void pll_channel_reset(DeviceState *dev)
+{
+    CprmanPllChannelState *s = CPRMAN_PLL_CHANNEL(dev);
+    const PLLChannelResetInfo *info = &PLL_CHANNEL_RESET_INFO[s->id];
+
+    *s->reg_a2w_ctrl = info->a2w_ctrl;
+}
+
 static bool pll_channel_is_enabled(CprmanPllChannelState *channel)
 {
     /*
      * XXX I'm not sure of the purpose of the LOAD field. The Linux driver does
      * not set it when enabling the channel, but does clear it when disabling
@@ -215,10 +235,11 @@  static const VMStateDescription pll_channel_vmstate = {
 
 static void pll_channel_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
+    dc->reset = pll_channel_reset;
     dc->vmsd = &pll_channel_vmstate;
 }
 
 static const TypeInfo cprman_pll_channel_info = {
     .name = TYPE_CPRMAN_PLL_CHANNEL,
@@ -284,10 +305,19 @@  static void clock_mux_src_update(void *opaque)
     }
 
     clock_mux_update(s);
 }
 
+static void clock_mux_reset(DeviceState *dev)
+{
+    CprmanClockMuxState *clock = CPRMAN_CLOCK_MUX(dev);
+    const ClockMuxResetInfo *info = &CLOCK_MUX_RESET_INFO[clock->id];
+
+    clock->reg_cm[0] = info->cm_ctrl;
+    clock->reg_cm[1] = info->cm_div;
+}
+
 static void clock_mux_init(Object *obj)
 {
     CprmanClockMuxState *s = CPRMAN_CLOCK_MUX(obj);
     size_t i;
 
@@ -316,10 +346,11 @@  static const VMStateDescription clock_mux_vmstate = {
 
 static void clock_mux_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
+    dc->reset = clock_mux_reset;
     dc->vmsd = &clock_mux_vmstate;
 }
 
 static const TypeInfo cprman_clock_mux_info = {
     .name = TYPE_CPRMAN_CLOCK_MUX,