[Qemu-devel] [PATCH v1 2/3] hw/ppc/pnv_occ: add sram device model for occ common area

[Balamuruhan S <bala24@linux.ibm.com>]

emulate occ common area region with occ sram device model which
occ and skiboot uses it to communicate regarding sensors, slw
and HWMON in PowerNV emulated host.

Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
---
 hw/ppc/pnv.c             |  8 +++++
 hw/ppc/pnv_occ.c         | 78 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/hw/ppc/pnv_occ.h |  3 ++
 3 files changed, 89 insertions(+)

diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index 3f08db7b9e..80338ffe87 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -938,6 +938,10 @@ static void pnv_chip_power8_realize(DeviceState *dev, Error **errp)
         return;
     }
     pnv_xscom_add_subregion(chip, PNV_XSCOM_OCC_BASE, &chip8->occ.xscom_regs);
+
+    /* OCC SRAM model */
+    memory_region_add_subregion(get_system_memory(), PNV_OCC_COMMON_AREA(chip),
+                                &chip8->occ.sram_regs);
 }
 
 static void pnv_chip_power8e_class_init(ObjectClass *klass, void *data)
@@ -1126,6 +1130,10 @@ static void pnv_chip_power9_realize(DeviceState *dev, Error **errp)
         return;
     }
     pnv_xscom_add_subregion(chip, PNV9_XSCOM_OCC_BASE, &chip9->occ.xscom_regs);
+
+    /* OCC SRAM model */
+    memory_region_add_subregion(get_system_memory(), PNV9_OCC_COMMON_AREA(chip),
+                                &chip9->occ.sram_regs);
 }
 
 static void pnv_chip_power9_class_init(ObjectClass *klass, void *data)
diff --git a/hw/ppc/pnv_occ.c b/hw/ppc/pnv_occ.c
index 8bead2c930..785653bb67 100644
--- a/hw/ppc/pnv_occ.c
+++ b/hw/ppc/pnv_occ.c
@@ -30,6 +30,24 @@
 #define OCB_OCI_OCCMISC_AND     0x4021
 #define OCB_OCI_OCCMISC_OR      0x4022
 
+/* OCC sensors */
+#define OCC_SENSOR_DATA_BLOCK_OFFSET          0x580000
+#define OCC_SENSOR_DATA_VALID                 0x580001
+#define OCC_SENSOR_DATA_VERSION               0x580002
+#define OCC_SENSOR_DATA_READING_VERSION       0x580004
+#define OCC_SENSOR_DATA_NR_SENSORS            0x580008
+#define OCC_SENSOR_DATA_NAMES_OFFSET          0x580010
+#define OCC_SENSOR_DATA_READING_PING_OFFSET   0x580014
+#define OCC_SENSOR_DATA_READING_PONG_OFFSET   0x58000c
+#define OCC_SENSOR_DATA_NAME_LENGTH           0x58000d
+#define OCC_SENSOR_NAME_STRUCTURE_TYPE        0x580023
+#define OCC_SENSOR_LOC_CORE                   0x580022
+#define OCC_SENSOR_LOC_GPU                    0x580020
+#define OCC_SENSOR_TYPE_POWER                 0x580003
+#define OCC_SENSOR_NAME                       0x580005
+#define HWMON_SENSORS_MASK                    0x58001e
+#define SLW_IMAGE_BASE                        0x0
+
 static void pnv_occ_set_misc(PnvOCC *occ, uint64_t val)
 {
     bool irq_state;
@@ -82,6 +100,48 @@ static void pnv_occ_power8_xscom_write(void *opaque, hwaddr addr,
     }
 }
 
+static uint64_t pnv_occ_common_area_read(void *opaque, hwaddr addr,
+                                         unsigned width)
+{
+    switch (addr) {
+    /*
+     * occ-sensor sanity check that asserts the sensor
+     * header block
+     */
+    case OCC_SENSOR_DATA_BLOCK_OFFSET:
+    case OCC_SENSOR_DATA_VALID:
+    case OCC_SENSOR_DATA_VERSION:
+    case OCC_SENSOR_DATA_READING_VERSION:
+    case OCC_SENSOR_DATA_NR_SENSORS:
+    case OCC_SENSOR_DATA_NAMES_OFFSET:
+    case OCC_SENSOR_DATA_READING_PING_OFFSET:
+    case OCC_SENSOR_DATA_READING_PONG_OFFSET:
+    case OCC_SENSOR_NAME_STRUCTURE_TYPE:
+        return 1;
+    case OCC_SENSOR_DATA_NAME_LENGTH:
+        return 0x30;
+    case OCC_SENSOR_LOC_CORE:
+        return 0x0040;
+    case OCC_SENSOR_TYPE_POWER:
+        return 0x0080;
+    case OCC_SENSOR_NAME:
+        return 0x1000;
+    case HWMON_SENSORS_MASK:
+    case OCC_SENSOR_LOC_GPU:
+        return 0x8e00;
+    case SLW_IMAGE_BASE:
+        return 0x1000000000000000;
+    }
+    return 0;
+}
+
+static void pnv_occ_common_area_write(void *opaque, hwaddr addr,
+                                             uint64_t val, unsigned width)
+{
+    /* callback function defined to occ common area write */
+    return;
+}
+
 static const MemoryRegionOps pnv_occ_power8_xscom_ops = {
     .read = pnv_occ_power8_xscom_read,
     .write = pnv_occ_power8_xscom_write,
@@ -92,12 +152,24 @@ static const MemoryRegionOps pnv_occ_power8_xscom_ops = {
     .endianness = DEVICE_BIG_ENDIAN,
 };
 
+const MemoryRegionOps pnv_occ_sram_ops = {
+    .read = pnv_occ_common_area_read,
+    .write = pnv_occ_common_area_write,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 8,
+    .impl.min_access_size = 1,
+    .impl.max_access_size = 8,
+    .endianness = DEVICE_BIG_ENDIAN,
+};
+
 static void pnv_occ_power8_class_init(ObjectClass *klass, void *data)
 {
     PnvOCCClass *poc = PNV_OCC_CLASS(klass);
 
     poc->xscom_size = PNV_XSCOM_OCC_SIZE;
+    poc->sram_size = PNV_OCC_COMMON_AREA_SIZE;
     poc->xscom_ops = &pnv_occ_power8_xscom_ops;
+    poc->sram_ops = &pnv_occ_sram_ops;
     poc->psi_irq = PSIHB_IRQ_OCC;
 }
 
@@ -168,7 +240,9 @@ static void pnv_occ_power9_class_init(ObjectClass *klass, void *data)
     PnvOCCClass *poc = PNV_OCC_CLASS(klass);
 
     poc->xscom_size = PNV9_XSCOM_OCC_SIZE;
+    poc->sram_size = PNV9_OCC_COMMON_AREA_SIZE;
     poc->xscom_ops = &pnv_occ_power9_xscom_ops;
+    poc->sram_ops = &pnv_occ_sram_ops;
     poc->psi_irq = PSIHB9_IRQ_OCC;
 }
 
@@ -199,6 +273,10 @@ static void pnv_occ_realize(DeviceState *dev, Error **errp)
     /* XScom region for OCC registers */
     pnv_xscom_region_init(&occ->xscom_regs, OBJECT(dev), poc->xscom_ops,
                           occ, "xscom-occ", poc->xscom_size);
+
+    /* XScom region for OCC SRAM registers */
+    pnv_xscom_region_init(&occ->sram_regs, OBJECT(dev), poc->sram_ops,
+                          occ, "occ-common-area", poc->sram_size);
 }
 
 static void pnv_occ_class_init(ObjectClass *klass, void *data)
diff --git a/include/hw/ppc/pnv_occ.h b/include/hw/ppc/pnv_occ.h
index ed0709bfc0..66b0989be6 100644
--- a/include/hw/ppc/pnv_occ.h
+++ b/include/hw/ppc/pnv_occ.h
@@ -38,6 +38,7 @@ typedef struct PnvOCC {
     PnvPsi *psi;
 
     MemoryRegion xscom_regs;
+    MemoryRegion sram_regs;
 } PnvOCC;
 
 #define PNV_OCC_CLASS(klass) \
@@ -49,7 +50,9 @@ typedef struct PnvOCCClass {
     DeviceClass parent_class;
 
     int xscom_size;
+    int sram_size;
     const MemoryRegionOps *xscom_ops;
+    const MemoryRegionOps *sram_ops;
     int psi_irq;
 } PnvOCCClass;
 
-- 
2.14.5