From 6acc6833510db8f72b5ef343296d97480555fda9 Mon Sep 17 00:00:00 2001 From: Anatolij Gustschin Date: Tue, 16 Feb 2010 22:30:03 -0700 Subject: [PATCH] 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 Signed-off-by: Anatolij Gustschin Acked-by: Greg Kroah-Hartman Signed-off-by: Grant Likely --- drivers/serial/mpc52xx_uart.c | 251 ++++++++++++++++++++++++++++++++-- 1 file changed, 236 insertions(+), 15 deletions(-) diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c index 7ce9e9f567a..3119fddaedb 100644 --- a/drivers/serial/mpc52xx_uart.c +++ b/drivers/serial/mpc52xx_uart.c @@ -74,6 +74,7 @@ #include #include #include +#include #include #include @@ -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); } -- 2.20.1