[PATCH 14/14] aspeed: Add I2C new register DMA slave mode support

[Peter Delevoryas]

Signed-off-by: Peter Delevoryas <pdel@fb.com>
---
 hw/i2c/aspeed_i2c.c         | 133 ++++++++++++++++++++++++++++++++----
 include/hw/i2c/aspeed_i2c.h |   3 +
 2 files changed, 124 insertions(+), 12 deletions(-)

diff --git a/hw/i2c/aspeed_i2c.c b/hw/i2c/aspeed_i2c.c
index 8a8514586f..fc8b6b62cf 100644
--- a/hw/i2c/aspeed_i2c.c
+++ b/hw/i2c/aspeed_i2c.c
@@ -78,6 +78,18 @@ static inline void 
aspeed_i2c_bus_raise_interrupt(AspeedI2CBus *bus)
     }
 }
 
+static inline void aspeed_i2c_bus_raise_slave_interrupt(AspeedI2CBus *bus)
+{
+    AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
+
+    if (!bus->regs[R_I2CS_INTR_STS]) {
+        return;
+    }
+
+    bus->controller->intr_status |= 1 << bus->id;
+    qemu_irq_raise(aic->bus_get_irq(bus));
+}
+
 static uint64_t aspeed_i2c_bus_old_read(AspeedI2CBus *bus, hwaddr offset,
                                         unsigned size)
 {
@@ -140,8 +152,17 @@ static uint64_t aspeed_i2c_bus_new_read(AspeedI2CBus *bus, 
hwaddr offset,
     case A_I2CM_DMA_LEN_STS:
     case A_I2CC_DMA_ADDR:
     case A_I2CC_DMA_LEN:
+
+    case A_I2CS_DEV_ADDR:
+    case A_I2CS_DMA_RX_ADDR:
+    case A_I2CS_DMA_LEN:
+    case A_I2CS_CMD:
+    case A_I2CS_INTR_CTRL:
+    case A_I2CS_DMA_LEN_STS:
         /* Value is already set, don't do anything. */
         break;
+    case A_I2CS_INTR_STS:
+        break;
     case A_I2CM_CMD:
         value = SHARED_FIELD_DP32(value, BUS_BUSY_STS, i2c_bus_busy(bus->bus));
         break;
@@ -547,12 +568,7 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus, 
hwaddr offset,
 
     switch (offset) {
     case A_I2CC_FUN_CTRL:
-        if (SHARED_FIELD_EX32(value, SLAVE_EN)) {
-            qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n",
-                          __func__);
-            break;
-        }
-        bus->regs[R_I2CC_FUN_CTRL] = value & 0x007dc3ff;
+        bus->regs[R_I2CC_FUN_CTRL] = value;
         break;
     case A_I2CC_AC_TIMING:
         bus->regs[R_I2CC_AC_TIMING] = value & 0x1ffff0ff;
@@ -580,6 +596,7 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus, 
hwaddr offset,
                 bus->controller->intr_status &= ~(1 << bus->id);
                 qemu_irq_lower(aic->bus_get_irq(bus));
             }
+            aspeed_i2c_bus_raise_slave_interrupt(bus);
             break;
         }
         bus->regs[R_I2CM_INTR_STS] &= ~(value & 0xf007f07f);
@@ -668,15 +685,53 @@ static void aspeed_i2c_bus_new_write(AspeedI2CBus *bus, 
hwaddr offset,
     case A_I2CC_DMA_LEN:
         /* RO */
         break;
-    case A_I2CS_DMA_LEN_STS:
-    case A_I2CS_DMA_TX_ADDR:
-    case A_I2CS_DMA_RX_ADDR:
     case A_I2CS_DEV_ADDR:
+        bus->regs[R_I2CS_DEV_ADDR] = value;
+        break;
+    case A_I2CS_DMA_RX_ADDR:
+        bus->regs[R_I2CS_DMA_RX_ADDR] = value;
+        break;
+    case A_I2CS_DMA_LEN:
+        assert(FIELD_EX32(value, I2CS_DMA_LEN, TX_BUF_LEN) == 0);
+        if (FIELD_EX32(value, I2CS_DMA_LEN, RX_BUF_LEN_W1T)) {
+            ARRAY_FIELD_DP32(bus->regs, I2CS_DMA_LEN, RX_BUF_LEN,
+                             FIELD_EX32(value, I2CS_DMA_LEN, RX_BUF_LEN));
+        } else {
+            bus->regs[R_I2CS_DMA_LEN] = value;
+        }
+        break;
+    case A_I2CS_CMD:
+        if (FIELD_EX32(value, I2CS_CMD, W1_CTRL)) {
+            bus->regs[R_I2CS_CMD] |= value;
+        } else {
+            bus->regs[R_I2CS_CMD] = value;
+        }
+        i2c_slave_set_address(bus->slave, bus->regs[R_I2CS_DEV_ADDR]);
+        break;
     case A_I2CS_INTR_CTRL:
+        bus->regs[R_I2CS_INTR_CTRL] = value;
+        break;
+
     case A_I2CS_INTR_STS:
-    case A_I2CS_CMD:
-    case A_I2CS_DMA_LEN:
-        qemu_log_mask(LOG_UNIMP, "%s: Slave mode is not implemented\n",
+        if (ARRAY_FIELD_EX32(bus->regs, I2CS_INTR_CTRL, PKT_CMD_DONE)) {
+            if (ARRAY_FIELD_EX32(bus->regs, I2CS_INTR_STS, PKT_CMD_DONE) &&
+                FIELD_EX32(value, I2CS_INTR_STS, PKT_CMD_DONE)) {
+                bus->regs[R_I2CS_INTR_STS] &= 0xfffc0000;
+            }
+        } else {
+            bus->regs[R_I2CS_INTR_STS] &= ~value;
+        }
+        if (!bus->regs[R_I2CS_INTR_STS]) {
+            bus->controller->intr_status &= ~(1 << bus->id);
+            qemu_irq_lower(aic->bus_get_irq(bus));
+        }
+        aspeed_i2c_bus_raise_interrupt(bus);
+        break;
+    case A_I2CS_DMA_LEN_STS:
+        bus->regs[R_I2CS_DMA_LEN_STS] = 0;
+        break;
+    case A_I2CS_DMA_TX_ADDR:
+        qemu_log_mask(LOG_UNIMP, "%s: Slave mode DMA TX is not implemented\n",
                       __func__);
         break;
     default:
@@ -1037,6 +1092,39 @@ static const TypeInfo aspeed_i2c_info = {
     .abstract   = true,
 };
 
+static int aspeed_i2c_bus_new_slave_event(AspeedI2CBus *bus,
+                                          enum i2c_event event)
+{
+    switch (event) {
+    case I2C_START_SEND_ASYNC:
+        if (!SHARED_ARRAY_FIELD_EX32(bus->regs, R_I2CS_CMD, RX_DMA_EN)) {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: Slave mode RX DMA is not enabled\n", __func__);
+            return -1;
+        }
+        ARRAY_FIELD_DP32(bus->regs, I2CS_DMA_LEN_STS, RX_LEN, 0);
+        bus->regs[R_I2CC_DMA_ADDR] =
+            ARRAY_FIELD_EX32(bus->regs, I2CS_DMA_RX_ADDR, ADDR);
+        bus->regs[R_I2CC_DMA_LEN] =
+            ARRAY_FIELD_EX32(bus->regs, I2CS_DMA_LEN, RX_BUF_LEN) + 1;
+        i2c_ack(bus->bus);
+        break;
+    case I2C_FINISH:
+        ARRAY_FIELD_DP32(bus->regs, I2CS_INTR_STS, PKT_CMD_DONE, 1);
+        ARRAY_FIELD_DP32(bus->regs, I2CS_INTR_STS, SLAVE_ADDR_RX_MATCH, 1);
+        SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CS_INTR_STS, NORMAL_STOP, 1);
+        SHARED_ARRAY_FIELD_DP32(bus->regs, R_I2CS_INTR_STS, RX_DONE, 1);
+        aspeed_i2c_bus_raise_slave_interrupt(bus);
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: i2c event %d unimplemented\n",
+                      __func__, event);
+        return -1;
+    }
+
+    return 0;
+}
+
 static int aspeed_i2c_bus_slave_event(I2CSlave *slave, enum i2c_event event)
 {
     BusState *qbus = qdev_get_parent_bus(DEVICE(slave));
@@ -1045,6 +1133,10 @@ static int aspeed_i2c_bus_slave_event(I2CSlave *slave, 
enum i2c_event event)
     uint32_t reg_byte_buf = aspeed_i2c_bus_byte_buf_offset(bus);
     uint32_t value;
 
+    if (aspeed_i2c_is_new_mode(bus->controller)) {
+        return aspeed_i2c_bus_new_slave_event(bus, event);
+    }
+
     switch (event) {
     case I2C_START_SEND_ASYNC:
         value = SHARED_ARRAY_FIELD_EX32(bus->regs, reg_byte_buf, TX_BUF);
@@ -1073,6 +1165,19 @@ static int aspeed_i2c_bus_slave_event(I2CSlave *slave, 
enum i2c_event event)
     return 0;
 }
 
+static void aspeed_i2c_bus_new_slave_send_async(AspeedI2CBus *bus, uint8_t 
data)
+{
+    assert(address_space_write(&bus->controller->dram_as,
+                               bus->regs[R_I2CC_DMA_ADDR],
+                               MEMTXATTRS_UNSPECIFIED, &data, 1) == MEMTX_OK);
+
+    bus->regs[R_I2CC_DMA_ADDR]++;
+    bus->regs[R_I2CC_DMA_LEN]--;
+    ARRAY_FIELD_DP32(bus->regs, I2CS_DMA_LEN_STS, RX_LEN,
+                     ARRAY_FIELD_EX32(bus->regs, I2CS_DMA_LEN_STS, RX_LEN) + 
1);
+    i2c_ack(bus->bus);
+}
+
 static void aspeed_i2c_bus_slave_send_async(I2CSlave *slave, uint8_t data)
 {
     BusState *qbus = qdev_get_parent_bus(DEVICE(slave));
@@ -1080,6 +1185,10 @@ static void aspeed_i2c_bus_slave_send_async(I2CSlave 
*slave, uint8_t data)
     uint32_t reg_intr_sts = aspeed_i2c_bus_intr_sts_offset(bus);
     uint32_t reg_byte_buf = aspeed_i2c_bus_byte_buf_offset(bus);
 
+    if (aspeed_i2c_is_new_mode(bus->controller)) {
+        return aspeed_i2c_bus_new_slave_send_async(bus, data);
+    }
+
     SHARED_ARRAY_FIELD_DP32(bus->regs, reg_byte_buf, RX_BUF, data);
     SHARED_ARRAY_FIELD_DP32(bus->regs, reg_intr_sts, RX_DONE, 1);
 
diff --git a/include/hw/i2c/aspeed_i2c.h b/include/hw/i2c/aspeed_i2c.h
index ba148b2f6d..300a89b343 100644
--- a/include/hw/i2c/aspeed_i2c.h
+++ b/include/hw/i2c/aspeed_i2c.h
@@ -174,6 +174,8 @@ REG32(I2CM_DMA_LEN, 0x1c)
     FIELD(I2CM_DMA_LEN, TX_BUF_LEN_W1T, 15, 1)
     FIELD(I2CM_DMA_LEN, TX_BUF_LEN, 0, 11)
 REG32(I2CS_INTR_CTRL, 0x20)
+    FIELD(I2CS_INTR_CTRL, PKT_CMD_FAIL, 17, 1)
+    FIELD(I2CS_INTR_CTRL, PKT_CMD_DONE, 16, 1)
 REG32(I2CS_INTR_STS, 0x24)
     /* 31:29 shared with I2CD_INTR_STS[31:29] */
     FIELD(I2CS_INTR_STS, SLAVE_PARKING_STS, 24, 2)
@@ -184,6 +186,7 @@ REG32(I2CS_INTR_STS, 0x24)
     FIELD(I2CS_INTR_STS, PKT_CMD_FAIL, 17, 1)
     FIELD(I2CS_INTR_STS, PKT_CMD_DONE, 16, 1)
     /* 14:0 shared with I2CD_INTR_STS[14:0] */
+    FIELD(I2CS_INTR_STS, SLAVE_ADDR_RX_MATCH, 7, 1)
 REG32(I2CS_CMD, 0x28)
     FIELD(I2CS_CMD, W1_CTRL, 31, 1)
     FIELD(I2CS_CMD, PKT_MODE_ACTIVE_ADDR, 17, 2)
-- 
2.30.2