Added default CS behaviour for SSI slaves. SSI devices can set a property
to enable CS behaviour which will create a GPIO on the device which is the
CS. Tristating of the bus on SSI transfers is implemented.
Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwa...@petalogix.com>
---
Changed since v5:
Addressed PMM review.
Collapsed into one patch for bisectability (this used to be two patches)
hw/ads7846.c | 7 ++++---
hw/max111x.c | 7 ++++---
hw/spitz.c | 8 +++++---
hw/ssd0323.c | 6 ++++++
hw/ssi-sd.c | 6 ++++++
hw/ssi.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++-
hw/ssi.h | 37 +++++++++++++++++++++++++++++++++++++
hw/stellaris.c | 7 ++++---
hw/z2.c | 7 ++++---
9 files changed, 118 insertions(+), 16 deletions(-)
diff --git a/hw/ads7846.c b/hw/ads7846.c
index 41c7f10..2ea9e55 100644
--- a/hw/ads7846.c
+++ b/hw/ads7846.c
@@ -119,11 +119,12 @@ static int ads7856_post_load(void *opaque, int version_id)
static const VMStateDescription vmstate_ads7846 = {
.name = "ads7846",
- .version_id = 0,
- .minimum_version_id = 0,
- .minimum_version_id_old = 0,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
.post_load = ads7856_post_load,
.fields = (VMStateField[]) {
+ VMSTATE_SSI_SLAVE(ssidev, ADS7846State),
VMSTATE_INT32_ARRAY(input, ADS7846State, 8),
VMSTATE_INT32(noise, ADS7846State),
VMSTATE_INT32(cycle, ADS7846State),
diff --git a/hw/max111x.c b/hw/max111x.c
index 706d89f..67640f1 100644
--- a/hw/max111x.c
+++ b/hw/max111x.c
@@ -99,10 +99,11 @@ static uint32_t max111x_transfer(SSISlave *dev, uint32_t
value)
static const VMStateDescription vmstate_max111x = {
.name = "max111x",
- .version_id = 0,
- .minimum_version_id = 0,
- .minimum_version_id_old = 0,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
.fields = (VMStateField[]) {
+ VMSTATE_SSI_SLAVE(ssidev, MAX111xState),
VMSTATE_UINT8(tb1, MAX111xState),
VMSTATE_UINT8(rb2, MAX111xState),
VMSTATE_UINT8(rb3, MAX111xState),
diff --git a/hw/spitz.c b/hw/spitz.c
index 20e7835..24346dc 100644
--- a/hw/spitz.c
+++ b/hw/spitz.c
@@ -1083,10 +1083,11 @@ static TypeInfo spitz_keyboard_info = {
static const VMStateDescription vmstate_corgi_ssp_regs = {
.name = "corgi-ssp",
- .version_id = 1,
- .minimum_version_id = 1,
- .minimum_version_id_old = 1,
+ .version_id = 2,
+ .minimum_version_id = 2,
+ .minimum_version_id_old = 2,
.fields = (VMStateField []) {
+ VMSTATE_SSI_SLAVE(ssidev, CorgiSSPState),
VMSTATE_UINT32_ARRAY(enable, CorgiSSPState, 3),
VMSTATE_END_OF_LIST(),
}
@@ -1115,6 +1116,7 @@ static const VMStateDescription vmstate_spitz_lcdtg_regs
= {
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField []) {
+ VMSTATE_SSI_SLAVE(ssidev, SpitzLCDTG),
VMSTATE_UINT32(bl_intensity, SpitzLCDTG),
VMSTATE_UINT32(bl_power, SpitzLCDTG),
VMSTATE_END_OF_LIST(),
diff --git a/hw/ssd0323.c b/hw/ssd0323.c
index b101c51..5d05a35 100644
--- a/hw/ssd0323.c
+++ b/hw/ssd0323.c
@@ -279,6 +279,7 @@ static void ssd0323_cd(void *opaque, int n, int level)
static void ssd0323_save(QEMUFile *f, void *opaque)
{
+ SSISlave *ss = SSI_SLAVE(opaque);
ssd0323_state *s = (ssd0323_state *)opaque;
int i;
@@ -296,10 +297,13 @@ static void ssd0323_save(QEMUFile *f, void *opaque)
qemu_put_be32(f, s->remap);
qemu_put_be32(f, s->mode);
qemu_put_buffer(f, s->framebuffer, sizeof(s->framebuffer));
+
+ qemu_put_be32(f, ss->cs);
}
static int ssd0323_load(QEMUFile *f, void *opaque, int version_id)
{
+ SSISlave *ss = SSI_SLAVE(opaque);
ssd0323_state *s = (ssd0323_state *)opaque;
int i;
@@ -321,6 +325,8 @@ static int ssd0323_load(QEMUFile *f, void *opaque, int
version_id)
s->mode = qemu_get_be32(f);
qemu_get_buffer(f, s->framebuffer, sizeof(s->framebuffer));
+ ss->cs = qemu_get_be32(f);
+
return 0;
}
diff --git a/hw/ssi-sd.c b/hw/ssi-sd.c
index b519bdb..cbbc645 100644
--- a/hw/ssi-sd.c
+++ b/hw/ssi-sd.c
@@ -197,6 +197,7 @@ static uint32_t ssi_sd_transfer(SSISlave *dev, uint32_t val)
static void ssi_sd_save(QEMUFile *f, void *opaque)
{
+ SSISlave *ss = SSI_SLAVE(opaque);
ssi_sd_state *s = (ssi_sd_state *)opaque;
int i;
@@ -209,10 +210,13 @@ static void ssi_sd_save(QEMUFile *f, void *opaque)
qemu_put_be32(f, s->arglen);
qemu_put_be32(f, s->response_pos);
qemu_put_be32(f, s->stopping);
+
+ qemu_put_be32(f, ss->cs);
}
static int ssi_sd_load(QEMUFile *f, void *opaque, int version_id)
{
+ SSISlave *ss = SSI_SLAVE(opaque);
ssi_sd_state *s = (ssi_sd_state *)opaque;
int i;
@@ -229,6 +233,8 @@ static int ssi_sd_load(QEMUFile *f, void *opaque, int
version_id)
s->response_pos = qemu_get_be32(f);
s->stopping = qemu_get_be32(f);
+ ss->cs = qemu_get_be32(f);
+
return 0;
}
diff --git a/hw/ssi.c b/hw/ssi.c
index 35d0a04..2e4f2fe 100644
--- a/hw/ssi.c
+++ b/hw/ssi.c
@@ -27,19 +27,55 @@ static const TypeInfo ssi_bus_info = {
.instance_size = sizeof(SSIBus),
};
+static void ssi_cs_default(void *opaque, int n, int level)
+{
+ SSISlave *s = SSI_SLAVE(opaque);
+ bool cs = !!level;
+ assert(n == 0);
+ if (s->cs != cs) {
+ SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);
+ if (ssc->set_cs) {
+ ssc->set_cs(s, cs);
+ }
+ }
+ s->cs = cs;
+}
+
+static uint32_t ssi_transfer_raw_default(SSISlave *dev, uint32_t val)
+{
+ SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev);
+
+ if ((dev->cs && ssc->cs_polarity == SSI_CS_HIGH) ||
+ (!dev->cs && ssc->cs_polarity == SSI_CS_LOW) ||
+ ssc->cs_polarity == SSI_CS_NONE) {
+ return ssc->transfer(dev, val);
+ }
+ return 0;
+}
+
static int ssi_slave_init(DeviceState *dev)
{
SSISlave *s = SSI_SLAVE(dev);
SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);
+ if (ssc->transfer_raw == ssi_transfer_raw_default &&
+ ssc->cs_polarity != SSI_CS_NONE) {
+ qdev_init_gpio_in(&s->qdev, ssi_cs_default, 1);
+ }
+
return ssc->init(s);
}
static void ssi_slave_class_init(ObjectClass *klass, void *data)
{
+ SSISlaveClass *ssc = SSI_SLAVE_CLASS(klass);
DeviceClass *dc = DEVICE_CLASS(klass);
+
dc->init = ssi_slave_init;
dc->bus_type = TYPE_SSI_BUS;
+ if (!ssc->transfer_raw) {
+ ssc->transfer_raw = ssi_transfer_raw_default;
+ }
}
static TypeInfo ssi_slave_info = {
@@ -74,12 +110,23 @@ uint32_t ssi_transfer(SSIBus *bus, uint32_t val)
QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {
SSISlave *slave = SSI_SLAVE(kid->child);
ssc = SSI_SLAVE_GET_CLASS(slave);
- r |= ssc->transfer(slave, val);
+ r |= ssc->transfer_raw(slave, val);
}
return r;
}
+const VMStateDescription vmstate_ssi_slave = {
+ .name = "SSISlave",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_BOOL(cs, SSISlave),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
static void ssi_slave_register_types(void)
{
type_register_static(&ssi_bus_info);
diff --git a/hw/ssi.h b/hw/ssi.h
index 06657d7..65b159d 100644
--- a/hw/ssi.h
+++ b/hw/ssi.h
@@ -23,21 +23,58 @@ typedef struct SSISlave SSISlave;
#define SSI_SLAVE_GET_CLASS(obj) \
OBJECT_GET_CLASS(SSISlaveClass, (obj), TYPE_SSI_SLAVE)
+typedef enum {
+ SSI_CS_NONE = 0,
+ SSI_CS_LOW,
+ SSI_CS_HIGH,
+} SSICSMode;
+
/* Slave devices. */
typedef struct SSISlaveClass {
DeviceClass parent_class;
int (*init)(SSISlave *dev);
+
+ /* if you have standard or no CS behaviour, just override transfer.
+ * This is called when the device cs is active (true by default).
+ */
uint32_t (*transfer)(SSISlave *dev, uint32_t val);
+ /* called when the CS line changes. Optional, devices only need to
implement
+ * this if they have side effects associated with the cs line (beyond
+ * tristating the txrx lines).
+ */
+ int (*set_cs)(SSISlave *dev, bool select);
+ /* define whether or not CS exists and is active low/high */
+ SSICSMode cs_polarity;
+
+ /* if you have non-standard CS behaviour override this to take control
+ * of the CS behaviour at the device level. transfer, set_cs, and
+ * cs_polarity are unused if this is overwritten. Transfer_raw will
+ * always be called for the device for every txrx access to the parent bus
+ */
+ uint32_t (*transfer_raw)(SSISlave *dev, uint32_t val);
} SSISlaveClass;
struct SSISlave {
DeviceState qdev;
+
+ /* Chip select state */
+ bool cs;
};
#define SSI_SLAVE_FROM_QDEV(dev) DO_UPCAST(SSISlave, qdev, dev)
#define FROM_SSI_SLAVE(type, dev) DO_UPCAST(type, ssidev, dev)
+extern const VMStateDescription vmstate_ssi_slave;
+
+#define VMSTATE_SSI_SLAVE(_field, _state) { \
+ .name = (stringify(_field)), \
+ .size = sizeof(SSISlave), \
+ .vmsd = &vmstate_ssi_slave, \
+ .flags = VMS_STRUCT, \
+ .offset = vmstate_offset_value(_state, _field, SSISlave), \
+}
+
DeviceState *ssi_create_slave(SSIBus *bus, const char *name);
/* Master interface. */
diff --git a/hw/stellaris.c b/hw/stellaris.c
index 562fbbf..01050d1 100644
--- a/hw/stellaris.c
+++ b/hw/stellaris.c
@@ -1184,10 +1184,11 @@ static uint32_t stellaris_ssi_bus_transfer(SSISlave
*dev, uint32_t val)
static const VMStateDescription vmstate_stellaris_ssi_bus = {
.name = "stellaris_ssi_bus",
- .version_id = 1,
- .minimum_version_id = 1,
- .minimum_version_id_old = 1,
+ .version_id = 2,
+ .minimum_version_id = 2,
+ .minimum_version_id_old = 2,
.fields = (VMStateField[]) {
+ VMSTATE_SSI_SLAVE(ssidev, stellaris_ssi_bus_state),
VMSTATE_INT32(current_dev, stellaris_ssi_bus_state),
VMSTATE_END_OF_LIST()
}
diff --git a/hw/z2.c b/hw/z2.c
index 289cee9..076fad2 100644
--- a/hw/z2.c
+++ b/hw/z2.c
@@ -161,10 +161,11 @@ static int zipit_lcd_init(SSISlave *dev)
static VMStateDescription vmstate_zipit_lcd_state = {
.name = "zipit-lcd",
- .version_id = 1,
- .minimum_version_id = 1,
- .minimum_version_id_old = 1,
+ .version_id = 2,
+ .minimum_version_id = 2,
+ .minimum_version_id_old = 2,
.fields = (VMStateField[]) {
+ VMSTATE_SSI_SLAVE(ssidev, ZipitLCD),
VMSTATE_INT32(selected, ZipitLCD),
VMSTATE_INT32(enabled, ZipitLCD),
VMSTATE_BUFFER(buf, ZipitLCD),
--
1.7.0.4
