[PATCH 07/14] hw/misc/bcm2835_cprman: add a PLL channel skeleton implementation

[Luc Michel]

PLLs are composed of multiple channels. Each channel outputs one clock
signal. They are modeled as one device taking the PLL generated clock as
input, and outputting a new clock.

A channel shares the cm register with its parent PLL, and has its own
a2w_ctrl register. A write to the cm register will trigger an update of
the PLL and all its channels, while a write to an a2w_ctrl channel
register will update the required channel only.

Signed-off-by: Luc Michel <luc@lmichel.fr>
---
 include/hw/misc/bcm2835_cprman.h           |  44 ++++++
 include/hw/misc/bcm2835_cprman_internals.h | 146 +++++++++++++++++++
 hw/misc/bcm2835_cprman.c                   | 155 +++++++++++++++++++--
 3 files changed, 337 insertions(+), 8 deletions(-)

diff --git a/include/hw/misc/bcm2835_cprman.h b/include/hw/misc/bcm2835_cprman.h
index f186ab0104..aaf15fb20c 100644
--- a/include/hw/misc/bcm2835_cprman.h
+++ b/include/hw/misc/bcm2835_cprman.h
@@ -29,10 +29,35 @@ typedef enum CprmanPLL {
     CPRMAN_PLLB,
 
     CPRMAN_NUM_PLL
 } CprmanPLL;
 
+typedef enum CprmanPLLChannel {
+    CPRMAN_PLLA_CHANNEL_DSI0 = 0,
+    CPRMAN_PLLA_CHANNEL_CORE,
+    CPRMAN_PLLA_CHANNEL_PER,
+    CPRMAN_PLLA_CHANNEL_CCP2,
+
+    CPRMAN_PLLC_CHANNEL_CORE2,
+    CPRMAN_PLLC_CHANNEL_CORE1,
+    CPRMAN_PLLC_CHANNEL_PER,
+    CPRMAN_PLLC_CHANNEL_CORE0,
+
+    CPRMAN_PLLD_CHANNEL_DSI0,
+    CPRMAN_PLLD_CHANNEL_CORE,
+    CPRMAN_PLLD_CHANNEL_PER,
+    CPRMAN_PLLD_CHANNEL_DSI1,
+
+    CPRMAN_PLLH_CHANNEL_AUX,
+    CPRMAN_PLLH_CHANNEL_RCAL,
+    CPRMAN_PLLH_CHANNEL_PIX,
+
+    CPRMAN_PLLB_CHANNEL_ARM,
+
+    CPRMAN_NUM_PLL_CHANNEL,
+} CprmanPLLChannel;
+
 typedef struct CprmanPLLState {
     /*< private >*/
     DeviceState parent_obj;
 
     /*< public >*/
@@ -46,18 +71,37 @@ typedef struct CprmanPLLState {
 
     Clock *xosc_in;
     Clock *out;
 } CprmanPLLState;
 
+typedef struct CprmanPLLChannelState {
+    /*< private >*/
+    DeviceState parent_obj;
+
+    /*< public >*/
+    CprmanPLLChannel id;
+    CprmanPLL parent;
+
+    uint32_t *reg_cm;
+    uint32_t hold_mask;
+    uint32_t load_mask;
+    uint32_t *reg_a2w_ctrl;
+    int fixed_divider;
+
+    Clock *pll_in;
+    Clock *out;
+} CprmanPLLChannelState;
+
 struct BCM2835CprmanState {
     /*< private >*/
     SysBusDevice parent_obj;
 
     /*< public >*/
     MemoryRegion iomem;
 
     CprmanPLLState plls[CPRMAN_NUM_PLL];
+    CprmanPLLChannelState channels[CPRMAN_NUM_PLL_CHANNEL];
 
     uint32_t regs[CPRMAN_NUM_REGS];
     uint32_t xosc_freq;
 
     Clock *xosc;
diff --git a/include/hw/misc/bcm2835_cprman_internals.h 
b/include/hw/misc/bcm2835_cprman_internals.h
index 22a2500ab0..8a5b9aae67 100644
--- a/include/hw/misc/bcm2835_cprman_internals.h
+++ b/include/hw/misc/bcm2835_cprman_internals.h
@@ -11,13 +11,16 @@
 
 #include "hw/registerfields.h"
 #include "hw/misc/bcm2835_cprman.h"
 
 #define TYPE_CPRMAN_PLL "bcm2835-cprman-pll"
+#define TYPE_CPRMAN_PLL_CHANNEL "bcm2835-cprman-pll-channel"
 
 DECLARE_INSTANCE_CHECKER(CprmanPLLState, CPRMAN_PLL,
                          TYPE_CPRMAN_PLL)
+DECLARE_INSTANCE_CHECKER(CprmanPLLChannelState, CPRMAN_PLL_CHANNEL,
+                         TYPE_CPRMAN_PLL_CHANNEL)
 
 /* Register map */
 
 /* PLLs */
 REG32(CM_PLLA, 0x104)
@@ -98,10 +101,35 @@ 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)
 
+/* PLL channels */
+REG32(A2W_PLLA_DSI0, 0x1300)
+    FIELD(A2W_PLLx_CHANNELy, DIV, 0, 8)
+    FIELD(A2W_PLLx_CHANNELy, DISABLE, 8, 1)
+REG32(A2W_PLLA_CORE, 0x1400)
+REG32(A2W_PLLA_PER, 0x1500)
+REG32(A2W_PLLA_CCP2, 0x1600)
+
+REG32(A2W_PLLC_CORE2, 0x1320)
+REG32(A2W_PLLC_CORE1, 0x1420)
+REG32(A2W_PLLC_PER, 0x1520)
+REG32(A2W_PLLC_CORE0, 0x1620)
+
+REG32(A2W_PLLD_DSI0, 0x1340)
+REG32(A2W_PLLD_CORE, 0x1440)
+REG32(A2W_PLLD_PER, 0x1540)
+REG32(A2W_PLLD_DSI1, 0x1640)
+
+REG32(A2W_PLLH_AUX, 0x1360)
+REG32(A2W_PLLH_RCAL, 0x1460)
+REG32(A2W_PLLH_PIX, 0x1560)
+REG32(A2W_PLLH_STS, 0x1660)
+
+REG32(A2W_PLLB_ARM, 0x13e0)
+
 /* misc registers */
 REG32(CM_LOCK, 0x114)
     FIELD(CM_LOCK, FLOCKH, 12, 1)
     FIELD(CM_LOCK, FLOCKD, 11, 1)
     FIELD(CM_LOCK, FLOCKC, 10, 1)
@@ -171,6 +199,124 @@ static inline void set_pll_init_info(BCM2835CprmanState 
*s,
     pll->reg_a2w_ana = &s->regs[PLL_INIT_INFO[id].a2w_ana_offset];
     pll->prediv_mask = PLL_INIT_INFO[id].prediv_mask;
     pll->reg_a2w_frac = &s->regs[PLL_INIT_INFO[id].a2w_frac_offset];
 }
 
+
+/* PLL channel init info */
+typedef struct PLLChannelInitInfo {
+    const char *name;
+    CprmanPLL parent;
+    size_t cm_offset;
+    uint32_t cm_hold_mask;
+    uint32_t cm_load_mask;
+    size_t a2w_ctrl_offset;
+    unsigned int fixed_divider;
+} PLLChannelInitInfo;
+
+#define FILL_PLL_CHANNEL_INIT_INFO_common(pll_, channel_)            \
+    .parent = CPRMAN_ ## pll_,                                       \
+    .cm_offset = R_CM_ ## pll_,                                      \
+    .cm_load_mask = R_CM_ ## pll_ ## _ ## LOAD ## channel_ ## _MASK, \
+    .a2w_ctrl_offset = R_A2W_ ## pll_ ## _ ## channel_
+
+#define FILL_PLL_CHANNEL_INIT_INFO(pll_, channel_)                   \
+    FILL_PLL_CHANNEL_INIT_INFO_common(pll_, channel_),               \
+    .cm_hold_mask = R_CM_ ## pll_ ## _ ## HOLD ## channel_ ## _MASK, \
+    .fixed_divider = 1
+
+#define FILL_PLL_CHANNEL_INIT_INFO_nohold(pll_, channel_) \
+    FILL_PLL_CHANNEL_INIT_INFO_common(pll_, channel_),    \
+    .cm_hold_mask = 0
+
+static PLLChannelInitInfo PLL_CHANNEL_INIT_INFO[] = {
+    [CPRMAN_PLLA_CHANNEL_DSI0] = {
+        .name = "plla-dsi0",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLA, DSI0),
+    },
+    [CPRMAN_PLLA_CHANNEL_CORE] = {
+        .name = "plla-core",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLA, CORE),
+    },
+    [CPRMAN_PLLA_CHANNEL_PER] = {
+        .name = "plla-per",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLA, PER),
+    },
+    [CPRMAN_PLLA_CHANNEL_CCP2] = {
+        .name = "plla-ccp2",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLA, CCP2),
+    },
+
+    [CPRMAN_PLLC_CHANNEL_CORE2] = {
+        .name = "pllc-core2",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLC, CORE2),
+    },
+    [CPRMAN_PLLC_CHANNEL_CORE1] = {
+        .name = "pllc-core1",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLC, CORE1),
+    },
+    [CPRMAN_PLLC_CHANNEL_PER] = {
+        .name = "pllc-per",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLC, PER),
+    },
+    [CPRMAN_PLLC_CHANNEL_CORE0] = {
+        .name = "pllc-core0",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLC, CORE0),
+    },
+
+    [CPRMAN_PLLD_CHANNEL_DSI0] = {
+        .name = "plld-dsi0",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLD, DSI0),
+    },
+    [CPRMAN_PLLD_CHANNEL_CORE] = {
+        .name = "plld-core",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLD, CORE),
+    },
+    [CPRMAN_PLLD_CHANNEL_PER] = {
+        .name = "plld-per",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLD, PER),
+    },
+    [CPRMAN_PLLD_CHANNEL_DSI1] = {
+        .name = "plld-dsi1",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLD, DSI1),
+    },
+
+    [CPRMAN_PLLH_CHANNEL_AUX] = {
+        .name = "pllh-aux",
+        .fixed_divider = 1,
+        FILL_PLL_CHANNEL_INIT_INFO_nohold(PLLH, AUX),
+    },
+    [CPRMAN_PLLH_CHANNEL_RCAL] = {
+        .name = "pllh-rcal",
+        .fixed_divider = 10,
+        FILL_PLL_CHANNEL_INIT_INFO_nohold(PLLH, RCAL),
+    },
+    [CPRMAN_PLLH_CHANNEL_PIX] = {
+        .name = "pllh-pix",
+        .fixed_divider = 10,
+        FILL_PLL_CHANNEL_INIT_INFO_nohold(PLLH, PIX),
+    },
+
+    [CPRMAN_PLLB_CHANNEL_ARM] = {
+        .name = "pllb-arm",
+        FILL_PLL_CHANNEL_INIT_INFO(PLLB, ARM),
+    },
+};
+
+#undef FILL_PLL_CHANNEL_INIT_INFO_nohold
+#undef FILL_PLL_CHANNEL_INIT_INFO
+#undef FILL_PLL_CHANNEL_INIT_INFO_common
+
+static inline void set_pll_channel_init_info(BCM2835CprmanState *s,
+                                             CprmanPLLChannelState *channel,
+                                             CprmanPLLChannel id)
+{
+    channel->id = id;
+    channel->parent = PLL_CHANNEL_INIT_INFO[id].parent;
+    channel->reg_cm = &s->regs[PLL_CHANNEL_INIT_INFO[id].cm_offset];
+    channel->hold_mask = PLL_CHANNEL_INIT_INFO[id].cm_hold_mask;
+    channel->load_mask = PLL_CHANNEL_INIT_INFO[id].cm_load_mask;
+    channel->reg_a2w_ctrl = 
&s->regs[PLL_CHANNEL_INIT_INFO[id].a2w_ctrl_offset];
+    channel->fixed_divider = PLL_CHANNEL_INIT_INFO[id].fixed_divider;
+}
+
 #endif
diff --git a/hw/misc/bcm2835_cprman.c b/hw/misc/bcm2835_cprman.c
index ba82522eb1..2c70a3f317 100644
--- a/hw/misc/bcm2835_cprman.c
+++ b/hw/misc/bcm2835_cprman.c
@@ -130,10 +130,73 @@ static const TypeInfo cprman_pll_info = {
     .class_init = pll_class_init,
     .instance_init = pll_init,
 };
 
 
+/* PLL channel */
+
+static void pll_channel_update(CprmanPLLChannelState *channel)
+{
+    clock_update(channel->out, 0);
+}
+
+/* Update a PLL and all its channels */
+static void pll_update_all_channels(BCM2835CprmanState *s,
+                                    CprmanPLLState *pll)
+{
+    size_t i;
+
+    pll_update(pll);
+
+    for (i = 0; i < CPRMAN_NUM_PLL_CHANNEL; i++) {
+        CprmanPLLChannelState *channel = &s->channels[i];
+        if (channel->parent == pll->id) {
+            pll_channel_update(channel);
+        }
+    }
+}
+
+static void pll_channel_pll_in_update(void *opaque)
+{
+    pll_channel_update(CPRMAN_PLL_CHANNEL(opaque));
+}
+
+static void pll_channel_init(Object *obj)
+{
+    CprmanPLLChannelState *s = CPRMAN_PLL_CHANNEL(obj);
+
+    s->pll_in = qdev_init_clock_in(DEVICE(s), "pll-in",
+                                   pll_channel_pll_in_update, s);
+    s->out = qdev_init_clock_out(DEVICE(s), "out");
+}
+
+static const VMStateDescription pll_channel_vmstate = {
+    .name = TYPE_CPRMAN_PLL_CHANNEL,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_CLOCK(pll_in, CprmanPLLChannelState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void pll_channel_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->vmsd = &pll_channel_vmstate;
+}
+
+static const TypeInfo cprman_pll_channel_info = {
+    .name = TYPE_CPRMAN_PLL_CHANNEL,
+    .parent = TYPE_DEVICE,
+    .instance_size = sizeof(CprmanPLLChannelState),
+    .class_init = pll_channel_class_init,
+    .instance_init = pll_channel_init,
+};
+
+
 /* CPRMAN "top level" model */
 
 static uint32_t get_cm_lock(const BCM2835CprmanState *s)
 {
     static const int CM_LOCK_MAPPING[] = {
@@ -172,12 +235,36 @@ static uint64_t cprman_read(void *opaque, hwaddr offset,
 
     trace_bcm2835_cprman_read(offset, r);
     return r;
 }
 
-#define CASE_PLL_REGS(pll_)       \
-    case R_CM_ ## pll_:           \
+static inline void update_pll_and_channels_from_cm(BCM2835CprmanState *s,
+                                                   size_t idx)
+{
+    size_t i;
+
+    for (i = 0; i < CPRMAN_NUM_PLL; i++) {
+        if (PLL_INIT_INFO[i].cm_offset == idx) {
+            pll_update_all_channels(s, &s->plls[i]);
+            return;
+        }
+    }
+}
+
+static inline void update_channel_from_a2w(BCM2835CprmanState *s, size_t idx)
+{
+    size_t i;
+
+    for (i = 0; i < CPRMAN_NUM_PLL_CHANNEL; i++) {
+        if (PLL_CHANNEL_INIT_INFO[i].a2w_ctrl_offset == idx) {
+            pll_channel_update(&s->channels[i]);
+            return;
+        }
+    }
+}
+
+#define CASE_PLL_A2W_REGS(pll_) \
     case R_A2W_ ## pll_ ## _CTRL: \
     case R_A2W_ ## pll_ ## _ANA0: \
     case R_A2W_ ## pll_ ## _ANA1: \
     case R_A2W_ ## pll_ ## _ANA2: \
     case R_A2W_ ## pll_ ## _ANA3: \
@@ -198,33 +285,61 @@ static void cprman_write(void *opaque, hwaddr offset,
 
     trace_bcm2835_cprman_write(offset, value);
     s->regs[idx] = value;
 
     switch (idx) {
-    CASE_PLL_REGS(PLLA) :
+    case R_CM_PLLA ... R_CM_PLLH:
+    case R_CM_PLLB:
+        /*
+         * A given CM_PLLx register is shared by both the PLL and the channels
+         * of this PLL.
+         */
+        update_pll_and_channels_from_cm(s, idx);
+        break;
+
+    CASE_PLL_A2W_REGS(PLLA) :
         pll_update(&s->plls[CPRMAN_PLLA]);
         break;
 
-    CASE_PLL_REGS(PLLC) :
+    CASE_PLL_A2W_REGS(PLLC) :
         pll_update(&s->plls[CPRMAN_PLLC]);
         break;
 
-    CASE_PLL_REGS(PLLD) :
+    CASE_PLL_A2W_REGS(PLLD) :
         pll_update(&s->plls[CPRMAN_PLLD]);
         break;
 
-    CASE_PLL_REGS(PLLH) :
+    CASE_PLL_A2W_REGS(PLLH) :
         pll_update(&s->plls[CPRMAN_PLLH]);
         break;
 
-    CASE_PLL_REGS(PLLB) :
+    CASE_PLL_A2W_REGS(PLLB) :
         pll_update(&s->plls[CPRMAN_PLLB]);
         break;
+
+    case R_A2W_PLLA_DSI0:
+    case R_A2W_PLLA_CORE:
+    case R_A2W_PLLA_PER:
+    case R_A2W_PLLA_CCP2:
+    case R_A2W_PLLC_CORE2:
+    case R_A2W_PLLC_CORE1:
+    case R_A2W_PLLC_PER:
+    case R_A2W_PLLC_CORE0:
+    case R_A2W_PLLD_DSI0:
+    case R_A2W_PLLD_CORE:
+    case R_A2W_PLLD_PER:
+    case R_A2W_PLLD_DSI1:
+    case R_A2W_PLLH_AUX:
+    case R_A2W_PLLH_RCAL:
+    case R_A2W_PLLH_PIX:
+    case R_A2W_PLLB_ARM:
+        update_channel_from_a2w(s, idx);
+        break;
     }
 }
 
-#undef CASE_PLL_REGS
+#undef CASE_PLL_A2W_REGS
 
 static const MemoryRegionOps cprman_ops = {
     .read = cprman_read,
     .write = cprman_write,
     .endianness = DEVICE_LITTLE_ENDIAN,
@@ -244,10 +359,14 @@ static void cprman_reset(DeviceState *dev)
 
     for (i = 0; i < CPRMAN_NUM_PLL; i++) {
         device_cold_reset(DEVICE(&s->plls[i]));
     }
 
+    for (i = 0; i < CPRMAN_NUM_PLL_CHANNEL; i++) {
+        device_cold_reset(DEVICE(&s->channels[i]));
+    }
+
     clock_update_hz(s->xosc, s->xosc_freq);
 }
 
 static Clock *init_internal_clock(BCM2835CprmanState *s,
                                   const char *name)
@@ -274,10 +393,17 @@ static void cprman_init(Object *obj)
         object_initialize_child(obj, PLL_INIT_INFO[i].name,
                                 &s->plls[i], TYPE_CPRMAN_PLL);
         set_pll_init_info(s, &s->plls[i], i);
     }
 
+    for (i = 0; i < CPRMAN_NUM_PLL_CHANNEL; i++) {
+        object_initialize_child(obj, PLL_CHANNEL_INIT_INFO[i].name,
+                                &s->channels[i],
+                                TYPE_CPRMAN_PLL_CHANNEL);
+        set_pll_channel_init_info(s, &s->channels[i], i);
+    }
+
     s->xosc = init_internal_clock(s, "xosc");
 
     memory_region_init_io(&s->iomem, obj, &cprman_ops,
                           s, "bcm2835-cprman", 0x2000);
     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
@@ -295,10 +421,22 @@ static void cprman_realize(DeviceState *dev, Error **errp)
 
         if (!qdev_realize(DEVICE(pll), NULL, errp)) {
             return;
         }
     }
+
+    for (i = 0; i < CPRMAN_NUM_PLL_CHANNEL; i++) {
+        CprmanPLLChannelState *channel = &s->channels[i];
+        CprmanPLL parent = PLL_CHANNEL_INIT_INFO[i].parent;
+        Clock *parent_clk = s->plls[parent].out;
+
+        clock_set_source(channel->pll_in, parent_clk);
+
+        if (!qdev_realize(DEVICE(channel), NULL, errp)) {
+            return;
+        }
+    }
 }
 
 static const VMStateDescription cprman_vmstate = {
     .name = TYPE_BCM2835_CPRMAN,
     .version_id = 1,
@@ -334,8 +472,9 @@ static const TypeInfo cprman_info = {
 
 static void cprman_register_types(void)
 {
     type_register_static(&cprman_info);
     type_register_static(&cprman_pll_info);
+    type_register_static(&cprman_pll_channel_info);
 }
 
 type_init(cprman_register_types);
-- 
2.28.0