2010-02-09 21:16:07

by Anatolij Gustschin

[permalink] [raw]
Subject: [PATCH v2 0/3] powerpc: mpc5121: PSC UART support

The support for mpc5121 PSC UART currently only works with
serial console. This patch series re-enable PSC UART support for
all 12 PSCs and document added DTS bingings.

Anatolij Gustschin (3):
serial: mpc52xx_uart: re-enable mpc5121 PSC UART support
powerpc: doc/dts-bindings: document mpc5121 psc uart dts-bindings
powerpc: mpc5121: enable support for more PSC UARTs

.../powerpc/dts-bindings/fsl/mpc5121-psc.txt | 70 ++++++
arch/powerpc/include/asm/mpc52xx_psc.h | 4 +
drivers/serial/mpc52xx_uart.c | 251 ++++++++++++++++++--
3 files changed, 310 insertions(+), 15 deletions(-)
create mode 100644 Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt


2010-02-09 21:16:28

by Anatolij Gustschin

[permalink] [raw]
Subject: [PATCH v2 1/3] serial: mpc52xx_uart: re-enable mpc5121 PSC UART support

Currently the support for MPC5121 PSC UART in the mpc52xx_uart
driver is broken (only console pre-initialized by the bootloader
works). Re-enable it now by providing MPC5121 specific ops
for PSCx clock activation, FIFO controller init/uninit and
MPC5121 PSC FIFO shared interrupt handling functions.

Signed-off-by: John Rigby <[email protected]>
Signed-off-by: Anatolij Gustschin <[email protected]>
Acked-by: Grant Likely <[email protected]>
---
Changes since v1:
- droped irq_dispose_mapping() entirely as suggested by Grant.
- added John's SoB as fifoc init code is based on his code. I
forgot to add the SoB in previous patch version, sorry.

drivers/serial/mpc52xx_uart.c | 251 ++++++++++++++++++++++++++++++++++++++---
1 files changed, 236 insertions(+), 15 deletions(-)

diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c
index 7ce9e9f..3119fdd 100644
--- a/drivers/serial/mpc52xx_uart.c
+++ b/drivers/serial/mpc52xx_uart.c
@@ -74,6 +74,7 @@
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_platform.h>
+#include <linux/clk.h>

#include <asm/mpc52xx.h>
#include <asm/mpc52xx_psc.h>
@@ -113,6 +114,7 @@ static void mpc52xx_uart_of_enumerate(void);

/* Forward declaration of the interruption handling routine */
static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
+static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);


/* Simple macro to test if a port is console or not. This one is taken
@@ -145,6 +147,11 @@ struct psc_ops {
void (*cw_disable_ints)(struct uart_port *port);
void (*cw_restore_ints)(struct uart_port *port);
unsigned long (*getuartclk)(void *p);
+ int (*clock)(struct uart_port *port, int enable);
+ int (*fifoc_init)(void);
+ void (*fifoc_uninit)(void);
+ void (*get_irq)(struct uart_port *, struct device_node *);
+ irqreturn_t (*handle_irq)(struct uart_port *port);
};

#ifdef CONFIG_PPC_MPC52xx
@@ -256,6 +263,18 @@ static unsigned long mpc52xx_getuartclk(void *p)
return mpc5xxx_get_bus_frequency(p) / 2;
}

+static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
+{
+ port->irqflags = IRQF_DISABLED;
+ port->irq = irq_of_parse_and_map(np, 0);
+}
+
+/* 52xx specific interrupt handler. The caller holds the port lock */
+static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
+{
+ return mpc5xxx_uart_process_int(port);
+}
+
static struct psc_ops mpc52xx_psc_ops = {
.fifo_init = mpc52xx_psc_fifo_init,
.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
@@ -273,14 +292,32 @@ static struct psc_ops mpc52xx_psc_ops = {
.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
.getuartclk = mpc52xx_getuartclk,
+ .get_irq = mpc52xx_psc_get_irq,
+ .handle_irq = mpc52xx_psc_handle_irq,
};

#endif /* CONFIG_MPC52xx */

#ifdef CONFIG_PPC_MPC512x
#define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
+
+/* PSC FIFO Controller for mpc512x */
+struct psc_fifoc {
+ u32 fifoc_cmd;
+ u32 fifoc_int;
+ u32 fifoc_dma;
+ u32 fifoc_axe;
+ u32 fifoc_debug;
+};
+
+static struct psc_fifoc __iomem *psc_fifoc;
+static unsigned int psc_fifoc_irq;
+
static void mpc512x_psc_fifo_init(struct uart_port *port)
{
+ /* /32 prescaler */
+ out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
+
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
out_be32(&FIFO_512x(port)->txalarm, 1);
@@ -393,6 +430,160 @@ static unsigned long mpc512x_getuartclk(void *p)
return mpc5xxx_get_bus_frequency(p);
}

+#define DEFAULT_FIFO_SIZE 16
+
+static unsigned int __init get_fifo_size(struct device_node *np,
+ char *fifo_name)
+{
+ const unsigned int *fp;
+
+ fp = of_get_property(np, fifo_name, NULL);
+ if (fp)
+ return *fp;
+
+ pr_warning("no %s property in %s node, defaulting to %d\n",
+ fifo_name, np->full_name, DEFAULT_FIFO_SIZE);
+
+ return DEFAULT_FIFO_SIZE;
+}
+
+#define FIFOC(_base) ((struct mpc512x_psc_fifo __iomem *) \
+ ((u32)(_base) + sizeof(struct mpc52xx_psc)))
+
+/* Init PSC FIFO Controller */
+static int __init mpc512x_psc_fifoc_init(void)
+{
+ struct device_node *np;
+ void __iomem *psc;
+ unsigned int tx_fifo_size;
+ unsigned int rx_fifo_size;
+ int fifobase = 0; /* current fifo address in 32 bit words */
+
+ np = of_find_compatible_node(NULL, NULL,
+ "fsl,mpc5121-psc-fifo");
+ if (!np) {
+ pr_err("%s: Can't find FIFOC node\n", __func__);
+ return -ENODEV;
+ }
+
+ psc_fifoc = of_iomap(np, 0);
+ if (!psc_fifoc) {
+ pr_err("%s: Can't map FIFOC\n", __func__);
+ return -ENODEV;
+ }
+
+ psc_fifoc_irq = irq_of_parse_and_map(np, 0);
+ of_node_put(np);
+ if (psc_fifoc_irq == NO_IRQ) {
+ pr_err("%s: Can't get FIFOC irq\n", __func__);
+ iounmap(psc_fifoc);
+ return -ENODEV;
+ }
+
+ for_each_compatible_node(np, NULL, "fsl,mpc5121-psc-uart") {
+ tx_fifo_size = get_fifo_size(np, "fsl,tx-fifo-size");
+ rx_fifo_size = get_fifo_size(np, "fsl,rx-fifo-size");
+
+ /* size in register is in 4 byte units */
+ tx_fifo_size /= 4;
+ rx_fifo_size /= 4;
+ if (!tx_fifo_size)
+ tx_fifo_size = 1;
+ if (!rx_fifo_size)
+ rx_fifo_size = 1;
+
+ psc = of_iomap(np, 0);
+ if (!psc) {
+ pr_err("%s: Can't map %s device\n",
+ __func__, np->full_name);
+ continue;
+ }
+
+ /* FIFO space is 4KiB, check if requested size is available */
+ if ((fifobase + tx_fifo_size + rx_fifo_size) > 0x1000) {
+ pr_err("%s: no fifo space available for %s\n",
+ __func__, np->full_name);
+ iounmap(psc);
+ /*
+ * chances are that another device requests less
+ * fifo space, so we continue.
+ */
+ continue;
+ }
+ /* set tx and rx fifo size registers */
+ out_be32(&FIFOC(psc)->txsz, (fifobase << 16) | tx_fifo_size);
+ fifobase += tx_fifo_size;
+ out_be32(&FIFOC(psc)->rxsz, (fifobase << 16) | rx_fifo_size);
+ fifobase += rx_fifo_size;
+
+ /* reset and enable the slices */
+ out_be32(&FIFOC(psc)->txcmd, 0x80);
+ out_be32(&FIFOC(psc)->txcmd, 0x01);
+ out_be32(&FIFOC(psc)->rxcmd, 0x80);
+ out_be32(&FIFOC(psc)->rxcmd, 0x01);
+
+ iounmap(psc);
+ }
+
+ return 0;
+}
+
+static void __exit mpc512x_psc_fifoc_uninit(void)
+{
+ iounmap(psc_fifoc);
+}
+
+/* 512x specific interrupt handler. The caller holds the port lock */
+static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
+{
+ unsigned long fifoc_int;
+ int psc_num;
+
+ /* Read pending PSC FIFOC interrupts */
+ fifoc_int = in_be32(&psc_fifoc->fifoc_int);
+
+ /* Check if it is an interrupt for this port */
+ psc_num = (port->mapbase & 0xf00) >> 8;
+ if (test_bit(psc_num, &fifoc_int) ||
+ test_bit(psc_num + 16, &fifoc_int))
+ return mpc5xxx_uart_process_int(port);
+
+ return IRQ_NONE;
+}
+
+static int mpc512x_psc_clock(struct uart_port *port, int enable)
+{
+ struct clk *psc_clk;
+ int psc_num;
+ char clk_name[10];
+
+ if (uart_console(port))
+ return 0;
+
+ psc_num = (port->mapbase & 0xf00) >> 8;
+ snprintf(clk_name, sizeof(clk_name), "psc%d_clk", psc_num);
+ psc_clk = clk_get(port->dev, clk_name);
+ if (IS_ERR(psc_clk)) {
+ dev_err(port->dev, "Failed to get PSC clock entry!\n");
+ return -ENODEV;
+ }
+
+ dev_dbg(port->dev, "%s %sable\n", clk_name, enable ? "en" : "dis");
+
+ if (enable)
+ clk_enable(psc_clk);
+ else
+ clk_disable(psc_clk);
+
+ return 0;
+}
+
+static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
+{
+ port->irqflags = IRQF_SHARED;
+ port->irq = psc_fifoc_irq;
+}
+
static struct psc_ops mpc512x_psc_ops = {
.fifo_init = mpc512x_psc_fifo_init,
.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
@@ -410,6 +601,11 @@ static struct psc_ops mpc512x_psc_ops = {
.cw_disable_ints = mpc512x_psc_cw_disable_ints,
.cw_restore_ints = mpc512x_psc_cw_restore_ints,
.getuartclk = mpc512x_getuartclk,
+ .clock = mpc512x_psc_clock,
+ .fifoc_init = mpc512x_psc_fifoc_init,
+ .fifoc_uninit = mpc512x_psc_fifoc_uninit,
+ .get_irq = mpc512x_psc_get_irq,
+ .handle_irq = mpc512x_psc_handle_irq,
};
#endif

@@ -519,10 +715,15 @@ mpc52xx_uart_startup(struct uart_port *port)
struct mpc52xx_psc __iomem *psc = PSC(port);
int ret;

+ if (psc_ops->clock) {
+ ret = psc_ops->clock(port, 1);
+ if (ret)
+ return ret;
+ }
+
/* Request IRQ */
ret = request_irq(port->irq, mpc52xx_uart_int,
- IRQF_DISABLED | IRQF_SAMPLE_RANDOM,
- "mpc52xx_psc_uart", port);
+ port->irqflags, "mpc52xx_psc_uart", port);
if (ret)
return ret;

@@ -553,6 +754,9 @@ mpc52xx_uart_shutdown(struct uart_port *port)
port->read_status_mask = 0;
out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);

+ if (psc_ops->clock)
+ psc_ops->clock(port, 0);
+
/* Release interrupt */
free_irq(port->irq, port);
}
@@ -851,15 +1055,12 @@ mpc52xx_uart_int_tx_chars(struct uart_port *port)
}

static irqreturn_t
-mpc52xx_uart_int(int irq, void *dev_id)
+mpc5xxx_uart_process_int(struct uart_port *port)
{
- struct uart_port *port = dev_id;
unsigned long pass = ISR_PASS_LIMIT;
unsigned int keepgoing;
u8 status;

- spin_lock(&port->lock);
-
/* While we have stuff to do, we continue */
do {
/* If we don't find anything to do, we stop */
@@ -886,11 +1087,23 @@ mpc52xx_uart_int(int irq, void *dev_id)

} while (keepgoing);

- spin_unlock(&port->lock);
-
return IRQ_HANDLED;
}

+static irqreturn_t
+mpc52xx_uart_int(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ irqreturn_t ret;
+
+ spin_lock(&port->lock);
+
+ ret = psc_ops->handle_irq(port);
+
+ spin_unlock(&port->lock);
+
+ return ret;
+}

/* ======================================================================== */
/* Console ( if applicable ) */
@@ -1152,7 +1365,7 @@ mpc52xx_uart_of_probe(struct of_device *op, const struct of_device_id *match)
return -EINVAL;
}

- port->irq = irq_of_parse_and_map(op->node, 0);
+ psc_ops->get_irq(port, op->node);
if (port->irq == NO_IRQ) {
dev_dbg(&op->dev, "Could not get irq\n");
return -EINVAL;
@@ -1163,10 +1376,8 @@ mpc52xx_uart_of_probe(struct of_device *op, const struct of_device_id *match)

/* Add the port to the uart sub-system */
ret = uart_add_one_port(&mpc52xx_uart_driver, port);
- if (ret) {
- irq_dispose_mapping(port->irq);
+ if (ret)
return ret;
- }

dev_set_drvdata(&op->dev, (void *)port);
return 0;
@@ -1178,10 +1389,8 @@ mpc52xx_uart_of_remove(struct of_device *op)
struct uart_port *port = dev_get_drvdata(&op->dev);
dev_set_drvdata(&op->dev, NULL);

- if (port) {
+ if (port)
uart_remove_one_port(&mpc52xx_uart_driver, port);
- irq_dispose_mapping(port->irq);
- }

return 0;
}
@@ -1288,6 +1497,15 @@ mpc52xx_uart_init(void)

mpc52xx_uart_of_enumerate();

+ /*
+ * Map the PSC FIFO Controller and init if on MPC512x.
+ */
+ if (psc_ops->fifoc_init) {
+ ret = psc_ops->fifoc_init();
+ if (ret)
+ return ret;
+ }
+
ret = of_register_platform_driver(&mpc52xx_uart_of_driver);
if (ret) {
printk(KERN_ERR "%s: of_register_platform_driver failed (%i)\n",
@@ -1302,6 +1520,9 @@ mpc52xx_uart_init(void)
static void __exit
mpc52xx_uart_exit(void)
{
+ if (psc_ops->fifoc_uninit)
+ psc_ops->fifoc_uninit();
+
of_unregister_platform_driver(&mpc52xx_uart_of_driver);
uart_unregister_driver(&mpc52xx_uart_driver);
}
--
1.6.3.3

2010-02-09 21:16:36

by Anatolij Gustschin

[permalink] [raw]
Subject: [PATCH v2 2/3] powerpc: doc/dts-bindings: document mpc5121 psc uart dts-bindings

Support for MPC5121 PSC UART in the mpc52xx_uart driver
added new DTS properties for FSL MPC5121 PSC FIFO Controller.
Provide documentation of the new properties and some examples.

Signed-off-by: Anatolij Gustschin <[email protected]>
Acked-by: Grant Likely <[email protected]>
---
No changes since v1.

.../powerpc/dts-bindings/fsl/mpc5121-psc.txt | 70 ++++++++++++++++++++
1 files changed, 70 insertions(+), 0 deletions(-)
create mode 100644 Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt

diff --git a/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt b/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt
new file mode 100644
index 0000000..8832e87
--- /dev/null
+++ b/Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt
@@ -0,0 +1,70 @@
+MPC5121 PSC Device Tree Bindings
+
+PSC in UART mode
+----------------
+
+For PSC in UART mode the needed PSC serial devices
+are specified by fsl,mpc5121-psc-uart nodes in the
+fsl,mpc5121-immr SoC node. Additionally the PSC FIFO
+Controller node fsl,mpc5121-psc-fifo is requered there:
+
+fsl,mpc5121-psc-uart nodes
+--------------------------
+
+Required properties :
+ - compatible : Should contain "fsl,mpc5121-psc-uart" and "fsl,mpc5121-psc"
+ - cell-index : Index of the PSC in hardware
+ - reg : Offset and length of the register set for the PSC device
+ - interrupts : <a b> where a is the interrupt number of the
+ PSC FIFO Controller and b is a field that represents an
+ encoding of the sense and level information for the interrupt.
+ - interrupt-parent : the phandle for the interrupt controller that
+ services interrupts for this device.
+
+Recommended properties :
+ - fsl,rx-fifo-size : the size of the RX fifo slice (a multiple of 4)
+ - fsl,tx-fifo-size : the size of the TX fifo slice (a multiple of 4)
+
+
+fsl,mpc5121-psc-fifo node
+-------------------------
+
+Required properties :
+ - compatible : Should be "fsl,mpc5121-psc-fifo"
+ - reg : Offset and length of the register set for the PSC
+ FIFO Controller
+ - interrupts : <a b> where a is the interrupt number of the
+ PSC FIFO Controller and b is a field that represents an
+ encoding of the sense and level information for the interrupt.
+ - interrupt-parent : the phandle for the interrupt controller that
+ services interrupts for this device.
+
+
+Example for a board using PSC0 and PSC1 devices in serial mode:
+
+serial@11000 {
+ compatible = "fsl,mpc5121-psc-uart", "fsl,mpc5121-psc";
+ cell-index = <0>;
+ reg = <0x11000 0x100>;
+ interrupts = <40 0x8>;
+ interrupt-parent = < &ipic >;
+ fsl,rx-fifo-size = <16>;
+ fsl,tx-fifo-size = <16>;
+};
+
+serial@11100 {
+ compatible = "fsl,mpc5121-psc-uart", "fsl,mpc5121-psc";
+ cell-index = <1>;
+ reg = <0x11100 0x100>;
+ interrupts = <40 0x8>;
+ interrupt-parent = < &ipic >;
+ fsl,rx-fifo-size = <16>;
+ fsl,tx-fifo-size = <16>;
+};
+
+pscfifo@11f00 {
+ compatible = "fsl,mpc5121-psc-fifo";
+ reg = <0x11f00 0x100>;
+ interrupts = <40 0x8>;
+ interrupt-parent = < &ipic >;
+};
--
1.6.3.3

2010-02-09 21:16:43

by Anatolij Gustschin

[permalink] [raw]
Subject: [PATCH v2 3/3] powerpc: mpc5121: enable support for more PSC UARTs

MPC5121 has 12 PSC devices. Enable UART support for all of
them by defining the number of max. PSCs depending on
selection of PPC_MPC512x platform support.

Signed-off-by: Anatolij Gustschin <[email protected]>
Acked-by: Grant Likely <[email protected]>
---
No changes since v1.

arch/powerpc/include/asm/mpc52xx_psc.h | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/include/asm/mpc52xx_psc.h b/arch/powerpc/include/asm/mpc52xx_psc.h
index fb84120..42561f4 100644
--- a/arch/powerpc/include/asm/mpc52xx_psc.h
+++ b/arch/powerpc/include/asm/mpc52xx_psc.h
@@ -25,7 +25,11 @@
#include <asm/types.h>

/* Max number of PSCs */
+#ifdef CONFIG_PPC_MPC512x
+#define MPC52xx_PSC_MAXNUM 12
+#else
#define MPC52xx_PSC_MAXNUM 6
+#endif

/* Programmable Serial Controller (PSC) status register bits */
#define MPC52xx_PSC_SR_UNEX_RX 0x0001
--
1.6.3.3

2010-02-09 22:19:22

by Grant Likely

[permalink] [raw]
Subject: Re: [PATCH v2 0/3] powerpc: mpc5121: PSC UART support

Greg, since this touches powerpc stuff, do you mind if I pick up the
series into my tree?

Thanks,
g.

On Tue, Feb 9, 2010 at 2:13 PM, Anatolij Gustschin <[email protected]> wrote:
> The support for mpc5121 PSC UART currently only works with
> serial console. This patch series re-enable PSC UART support for
> all 12 PSCs and document added DTS bingings.
>
> Anatolij Gustschin (3):
> ?serial: mpc52xx_uart: re-enable mpc5121 PSC UART support
> ?powerpc: doc/dts-bindings: document mpc5121 psc uart ?dts-bindings
> ?powerpc: mpc5121: enable support for more PSC UARTs
>
> ?.../powerpc/dts-bindings/fsl/mpc5121-psc.txt ? ? ? | ? 70 ++++++
> ?arch/powerpc/include/asm/mpc52xx_psc.h ? ? ? ? ? ? | ? ?4 +
> ?drivers/serial/mpc52xx_uart.c ? ? ? ? ? ? ? ? ? ? ?| ?251 ++++++++++++++++++--
> ?3 files changed, 310 insertions(+), 15 deletions(-)
> ?create mode 100644 Documentation/powerpc/dts-bindings/fsl/mpc5121-psc.txt
>
>



--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.

2010-02-09 22:41:07

by Greg KH

[permalink] [raw]
Subject: Re: [PATCH v2 0/3] powerpc: mpc5121: PSC UART support

On Tue, Feb 09, 2010 at 03:18:57PM -0700, Grant Likely wrote:
> Greg, since this touches powerpc stuff, do you mind if I pick up the
> series into my tree?

No objection at all, feel free to add an:
Acked-by: Greg Kroah-Hartman <[email protected]>
to the patches.

thanks,

greg k-h