[Skiboot] [PATCH 10/33] uart: Cleanup initialization and remove simulator hack
Benjamin Herrenschmidt
benh at kernel.crashing.org
Sat Jun 25 08:47:33 AEST 2016
Add more generic support for MMIO based UARTs, simplify code,
use common initialization, and clean up the device-tree
representation as well.
Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
---
core/init.c | 7 ++-
core/platform.c | 8 ++-
hw/lpc-uart.c | 152 ++++++++++++++++++++--------------------------
include/console.h | 1 -
include/skiboot.h | 3 +-
platforms/astbmc/common.c | 4 +-
platforms/qemu/qemu.c | 8 +--
platforms/rhesus/rhesus.c | 8 +--
8 files changed, 85 insertions(+), 106 deletions(-)
diff --git a/core/init.c b/core/init.c
index 67b539b..48f5322 100644
--- a/core/init.c
+++ b/core/init.c
@@ -657,10 +657,13 @@ void __noreturn main_cpu_entry(const void *fdt, u32 master_cpu)
* to access chips via that path early on.
*/
init_chips();
+
+ /* If we detect the mambo simulator, we can enable its special console
+ * early on. Do that now.
+ */
if (chip_quirk(QUIRK_MAMBO_CALLOUTS))
enable_mambo_console();
- if (chip_quirk(QUIRK_SIMICS))
- enable_simics_console();
+
xscom_init();
mfsi_init();
diff --git a/core/platform.c b/core/platform.c
index 371cf42..de6e406 100644
--- a/core/platform.c
+++ b/core/platform.c
@@ -98,7 +98,13 @@ opal_call(OPAL_CEC_REBOOT2, opal_cec_reboot2, 2);
static void generic_platform_init(void)
{
- force_dummy_console();
+ /* Enable a UART if we find one in the device-tree */
+ uart_init();
+
+ if (uart_enabled())
+ uart_setup_opal_console();
+ else
+ force_dummy_console();
fake_rtc_init();
}
diff --git a/hw/lpc-uart.c b/hw/lpc-uart.c
index 433cdff..6693265 100644
--- a/hw/lpc-uart.c
+++ b/hw/lpc-uart.c
@@ -64,11 +64,10 @@ DEFINE_LOG_ENTRY(OPAL_RC_UART_INIT, OPAL_PLATFORM_ERR_EVT, OPAL_UART,
static struct lock uart_lock = LOCK_UNLOCKED;
static struct dt_node *uart_node;
static uint32_t uart_base;
-static bool has_irq, irq_ok, rx_full, tx_full;
+static bool has_irq = false, irq_ok, rx_full, tx_full;
static uint8_t tx_room;
static uint8_t cached_ier;
-static bool simics_uart;
-static void *simics_uart_base;
+static void *mmio_uart_base;
static void uart_trace(u8 ctx, u8 cnt, u8 irq_state, u8 in_count)
{
@@ -83,16 +82,16 @@ static void uart_trace(u8 ctx, u8 cnt, u8 irq_state, u8 in_count)
static inline uint8_t uart_read(unsigned int reg)
{
- if (simics_uart)
- return in_8(simics_uart_base + reg);
+ if (mmio_uart_base)
+ return in_8(mmio_uart_base + reg);
else
return lpc_inb(uart_base + reg);
}
static inline void uart_write(unsigned int reg, uint8_t val)
{
- if (simics_uart)
- out_8(simics_uart_base + reg, val);
+ if (mmio_uart_base)
+ out_8(mmio_uart_base + reg, val);
else
lpc_outb(val, uart_base + reg);
}
@@ -121,6 +120,7 @@ static void uart_update_ier(void)
if (!has_irq)
return;
+
/* If we have never got an interrupt, enable them all,
* the first interrupt received will tell us if interrupts
* are functional (some boards are missing an EC or FPGA
@@ -138,6 +138,11 @@ static void uart_update_ier(void)
}
}
+bool uart_enabled(void)
+{
+ return mmio_uart_base || uart_base;
+}
+
/*
* Internal console driver (output only)
*/
@@ -146,7 +151,7 @@ static size_t uart_con_write(const char *buf, size_t len)
size_t written = 0;
/* If LPC bus is bad, we just swallow data */
- if (!lpc_ok() && !simics_uart)
+ if (!lpc_ok() && !mmio_uart_base)
return written;
lock(&uart_lock);
@@ -362,7 +367,7 @@ static int64_t uart_opal_read(int64_t term_number, int64_t *length,
uart_trace(TRACE_UART_CTX_READ, read_cnt, tx_full, in_count);
unlock(&uart_lock);
-
+
/* Adjust the OPAL event */
uart_adjust_opal_event();
@@ -492,15 +497,13 @@ static struct lpc_client uart_lpc_client = {
.interrupt = uart_irq,
};
-void uart_init(bool use_interrupt)
+void uart_init(void)
{
const struct dt_property *prop;
struct dt_node *n;
char *path __unused;
- uint32_t chip_id, irq;
-
- if (!lpc_present())
- return;
+ uint32_t chip_id;
+ const uint32_t *irqp;
/* UART lock is in the console path and thus must block
* printf re-entrancy
@@ -512,19 +515,55 @@ void uart_init(bool use_interrupt)
if (!n)
return;
- /* Get IO base */
- prop = dt_find_property(n, "reg");
- if (!prop) {
- log_simple_error(&e_info(OPAL_RC_UART_INIT),
- "UART: Can't find reg property\n");
- return;
- }
- if (dt_property_get_cell(prop, 0) != OPAL_LPC_IO) {
- log_simple_error(&e_info(OPAL_RC_UART_INIT),
- "UART: Only supports IO addresses\n");
- return;
+ /* Read the interrupts property if any */
+ irqp = dt_prop_get_def(n, "interrupts", NULL);
+
+ /* Now check if the UART is on the root bus. This is the case of
+ * directly mapped UARTs in simulation environments
+ */
+ if (n->parent == dt_root) {
+ printf("UART: Found at root !\n");
+ mmio_uart_base = (void *)dt_translate_address(n, 0, NULL);
+ if (!mmio_uart_base) {
+ printf("UART: Failed to translate address !\n");
+ return;
+ }
+
+ /* If it has an interrupt properly, we consider this to be
+ * a direct XICS/XIVE interrupt
+ */
+ if (irqp)
+ has_irq = true;
+
+ } else {
+ if (!lpc_present())
+ return;
+
+ /* Get IO base */
+ prop = dt_find_property(n, "reg");
+ if (!prop) {
+ log_simple_error(&e_info(OPAL_RC_UART_INIT),
+ "UART: Can't find reg property\n");
+ return;
+ }
+ if (dt_property_get_cell(prop, 0) != OPAL_LPC_IO) {
+ log_simple_error(&e_info(OPAL_RC_UART_INIT),
+ "UART: Only supports IO addresses\n");
+ return;
+ }
+ uart_base = dt_property_get_cell(prop, 1);
+
+ if (irqp) {
+ uint32_t irq = be32_to_cpu(*irqp);
+
+ chip_id = dt_get_chip_id(uart_node);
+ uart_lpc_client.interrupts = LPC_IRQ(irq);
+ lpc_register_client(chip_id, &uart_lpc_client);
+ prlog(PR_DEBUG, "UART: Using LPC IRQ %d\n", irq);
+ has_irq = true;
+ }
}
- uart_base = dt_property_get_cell(prop, 1);
+
if (!uart_init_hw(dt_prop_get_u32(n, "current-speed"),
dt_prop_get_u32(n, "clock-frequency"))) {
@@ -532,7 +571,6 @@ void uart_init(bool use_interrupt)
dt_add_property_strings(n, "status", "bad");
return;
}
- chip_id = dt_get_chip_id(uart_node);
/*
* Mark LPC used by the console (will mark the relevant
@@ -542,65 +580,5 @@ void uart_init(bool use_interrupt)
/* Install console backend for printf() */
set_console(&uart_con_driver);
-
- /* On Naples, use the SerIRQ, which Linux will have to share with
- * OPAL as we don't really play the cascaded interrupt game at this
- * point...
- */
- if (use_interrupt) {
- irq = dt_prop_get_u32(n, "interrupts");
- uart_lpc_client.interrupts = LPC_IRQ(irq);
- lpc_register_client(chip_id, &uart_lpc_client);
- has_irq = true;
- prlog(PR_DEBUG, "UART: Using LPC IRQ %d\n", irq);
- } else
- has_irq = false;
-}
-
-static bool simics_con_poll_read(void) {
- uint8_t lsr = uart_read(REG_LSR);
- return ((lsr & LSR_DR) != 0);
}
-static size_t simics_con_read(char *buf, size_t len)
-{
- size_t count = 0;
- while (count < len) {
- if (!simics_con_poll_read())
- break;
- *(buf++) = uart_read(REG_RBR);
- count++;
- }
- return count;
-}
-
-static struct con_ops simics_con_driver = {
- .poll_read = simics_con_poll_read,
- .read = simics_con_read,
- .write = uart_con_write,
-};
-
-void enable_simics_console() {
- struct dt_node *n;
-
- printf("Enabling Simics console\n");
-
- n = dt_find_compatible_node(dt_root, NULL, "ns16550");
- if (!n) {
- prerror("UART: cannot find ns16550\n");
- return;
- }
-
- simics_uart_base = (void *)dt_prop_get_u64(n, "console-bar");
- simics_uart = 1;
- has_irq = false;
-
- if (!uart_init_hw(dt_prop_get_u32(n, "current-speed"),
- dt_prop_get_u32(n, "clock-frequency"))) {
- prerror("UART: Initialization failed\n");
- dt_add_property_strings(n, "status", "bad");
- return;
- }
-
- set_console(&simics_con_driver);
-}
diff --git a/include/console.h b/include/console.h
index ecb18c4..b6fc8bf 100644
--- a/include/console.h
+++ b/include/console.h
@@ -67,7 +67,6 @@ extern void console_complete_flush(void);
extern int mambo_read(void);
extern void mambo_write(const char *buf, size_t count);
extern void enable_mambo_console(void);
-extern void enable_simics_console(void);
ssize_t console_write(bool flush_to_drivers, const void *buf, size_t count);
diff --git a/include/skiboot.h b/include/skiboot.h
index ded6bb8..1d33389 100644
--- a/include/skiboot.h
+++ b/include/skiboot.h
@@ -203,7 +203,7 @@ extern void probe_phb3(void);
extern int phb3_preload_capp_ucode(void);
extern void phb3_preload_vpd(void);
extern void probe_npu(void);
-extern void uart_init(bool enable_interrupt);
+extern void uart_init(void);
extern void homer_init(void);
extern void occ_pstates_init(void);
extern void slw_init(void);
@@ -228,6 +228,7 @@ extern void nvram_read_complete(bool success);
/* UART stuff */
extern void uart_setup_linux_passthrough(void);
extern void uart_setup_opal_console(void);
+extern bool uart_enabled(void);
/* OCC interrupt */
extern void occ_interrupt(uint32_t chip_id);
diff --git a/platforms/astbmc/common.c b/platforms/astbmc/common.c
index 1ed7d42..0699a44 100644
--- a/platforms/astbmc/common.c
+++ b/platforms/astbmc/common.c
@@ -347,8 +347,8 @@ void astbmc_early_init(void)
/* Similarly, some BMCs don't configure the BT interrupt properly */
ast_setup_ibt(BT_IO_BASE, BT_LPC_IRQ);
- /* Setup UART and use it as console with interrupts */
- uart_init(true);
+ /* Setup UART and use it as console */
+ uart_init();
prd_init();
}
diff --git a/platforms/qemu/qemu.c b/platforms/qemu/qemu.c
index 66a6aa3..a7d2889 100644
--- a/platforms/qemu/qemu.c
+++ b/platforms/qemu/qemu.c
@@ -130,12 +130,8 @@ static bool qemu_probe(void)
psi_set_external_irq_policy(EXTERNAL_IRQ_POLICY_SKIBOOT);
- /*
- * Setup UART and use it as console. For now, we
- * don't expose the interrupt as we know it's not
- * working properly yet
- */
- uart_init(true);
+ /* Setup UART and use it as console */
+ uart_init();
return true;
}
diff --git a/platforms/rhesus/rhesus.c b/platforms/rhesus/rhesus.c
index 3e2c41b..a3af777 100644
--- a/platforms/rhesus/rhesus.c
+++ b/platforms/rhesus/rhesus.c
@@ -270,12 +270,8 @@ static bool rhesus_probe(void)
/* Add missing bits of device-tree such as the UART */
rhesus_dt_fixup(has_uart_irq);
- /*
- * Setup UART and use it as console. For now, we
- * don't expose the interrupt as we know it's not
- * working properly yet
- */
- uart_init(has_uart_irq);
+ /* Setup UART and use it as console */
+ uart_init();
return true;
}
--
2.7.4
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