/*
 *  Driver for CPM (SCC/SMC) serial ports; CPM2 definitions
 *
 *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
 *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
 *
 *  Copyright (C) 2004 Freescale Semiconductor, Inc.
 *            (C) 2004 Intracom, S.A.
 *            (C) 2006 MontaVista Software, Inc.
 *              Vitaly Bordug <vbordug@ru.mvista.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/device.h>
#include <linux/bootmem.h>
#include <linux/dma-mapping.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/fs_pd.h>
#include <asm/prom.h>

#include <linux/serial_core.h>
#include <linux/kernel.h>

#include "cpm_uart.h"

/**************************************************************/

void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
{
        cpm_command(port->command, cmd);
}

void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
                                struct device_node *np)
{
        void __iomem *pram;
        unsigned long offset;
        struct resource res;
        resource_size_t len;

        /* Don't remap parameter RAM if it has already been initialized
         * during console setup.
         */
        if (IS_SMC(port) && port->smcup)
                return port->smcup;
        else if (!IS_SMC(port) && port->sccup)
                return port->sccup;

        if (of_address_to_resource(np, 1, &res))
                return NULL;

        len = resource_size(&res);
        pram = ioremap(res.start, len);
        if (!pram)
                return NULL;

        if (!IS_SMC(port))
                return pram;

        if (len != 2) {
                printk(KERN_WARNING "cpm_uart[%d]: device tree references "
                        "SMC pram, using boot loader/wrapper pram mapping. "
                        "Please fix your device tree to reference the pram "
                        "base register instead.\n",
                        port->port.line);
                return pram;
        }

        offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
        out_be16(pram, offset);
        iounmap(pram);
        return cpm_muram_addr(offset);
}

void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
{
        if (!IS_SMC(port))
                iounmap(pram);
}

/*
 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
 * receive buffer descriptors from dual port ram, and a character
 * buffer area from host mem. If we are allocating for the console we need
 * to do it from bootmem
 */
int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
{
        int dpmemsz, memsz;
        u8 __iomem *dp_mem;
        unsigned long dp_offset;
        u8 *mem_addr;
        dma_addr_t dma_addr = 0;

        pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);

        dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
        dp_offset = cpm_dpalloc(dpmemsz, 8);
        if (IS_ERR_VALUE(dp_offset)) {
                printk(KERN_ERR
                       "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
                return -ENOMEM;
        }

        dp_mem = cpm_dpram_addr(dp_offset);

        memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
            L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
        if (is_con) {
                mem_addr = kzalloc(memsz, GFP_NOWAIT);
                dma_addr = virt_to_bus(mem_addr);
        }
        else
                mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
                                              GFP_KERNEL);

        if (mem_addr == NULL) {
                cpm_dpfree(dp_offset);
                printk(KERN_ERR
                       "cpm_uart_cpm.c: could not allocate coherent memory\n");
                return -ENOMEM;
        }

        pinfo->dp_addr = dp_offset;
        pinfo->mem_addr = mem_addr;
        pinfo->dma_addr = dma_addr;
        pinfo->mem_size = memsz;

        pinfo->rx_buf = mem_addr;
        pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
                                                       * pinfo->rx_fifosize);

        pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
        pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;

        return 0;
}

void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
{
        dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
                                                          pinfo->rx_fifosize) +
                          L1_CACHE_ALIGN(pinfo->tx_nrfifos *
                                         pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
                          pinfo->dma_addr);

        cpm_dpfree(pinfo->dp_addr);
}