1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *  Driver for CPM (SCC/SMC) serial ports; CPM2 definitions
  4 *
  5 *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
  6 *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
  7 *
  8 *  Copyright (C) 2004 Freescale Semiconductor, Inc.
  9 *            (C) 2004 Intracom, S.A.
 10 *            (C) 2006 MontaVista Software, Inc.
 11 *		Vitaly Bordug <vbordug@ru.mvista.com>
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/tty.h>
 16#include <linux/ioport.h>
 17#include <linux/slab.h>
 18#include <linux/serial.h>
 19#include <linux/console.h>
 20#include <linux/sysrq.h>
 21#include <linux/device.h>
 22#include <linux/memblock.h>
 23#include <linux/dma-mapping.h>
 24
 25#include <asm/io.h>
 26#include <asm/irq.h>
 27#include <asm/fs_pd.h>
 28#include <asm/prom.h>
 29
 30#include <linux/serial_core.h>
 31#include <linux/kernel.h>
 32
 33#include "cpm_uart.h"
 34
 35/**************************************************************/
 36
 37void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
 38{
 39	cpm_command(port->command, cmd);
 40}
 41
 42void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
 43				struct device_node *np)
 44{
 45	void __iomem *pram;
 46	unsigned long offset;
 47	struct resource res;
 48	resource_size_t len;
 49
 50	/* Don't remap parameter RAM if it has already been initialized
 51	 * during console setup.
 52	 */
 53	if (IS_SMC(port) && port->smcup)
 54		return port->smcup;
 55	else if (!IS_SMC(port) && port->sccup)
 56		return port->sccup;
 57
 58	if (of_address_to_resource(np, 1, &res))
 59		return NULL;
 60
 61	len = resource_size(&res);
 62	pram = ioremap(res.start, len);
 63	if (!pram)
 64		return NULL;
 65
 66	if (!IS_SMC(port))
 67		return pram;
 68
 69	if (len != 2) {
 70		printk(KERN_WARNING "cpm_uart[%d]: device tree references "
 71			"SMC pram, using boot loader/wrapper pram mapping. "
 72			"Please fix your device tree to reference the pram "
 73			"base register instead.\n",
 74			port->port.line);
 75		return pram;
 76	}
 77
 78	offset = cpm_dpalloc(PROFF_SMC_SIZE, 64);
 79	out_be16(pram, offset);
 80	iounmap(pram);
 81	return cpm_muram_addr(offset);
 82}
 83
 84void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
 85{
 86	if (!IS_SMC(port))
 87		iounmap(pram);
 88}
 89
 90/*
 91 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
 92 * receive buffer descriptors from dual port ram, and a character
 93 * buffer area from host mem. If we are allocating for the console we need
 94 * to do it from bootmem
 95 */
 96int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
 97{
 98	int dpmemsz, memsz;
 99	u8 __iomem *dp_mem;
100	unsigned long dp_offset;
101	u8 *mem_addr;
102	dma_addr_t dma_addr = 0;
103
104	pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
105
106	dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
107	dp_offset = cpm_dpalloc(dpmemsz, 8);
108	if (IS_ERR_VALUE(dp_offset)) {
109		printk(KERN_ERR
110		       "cpm_uart_cpm.c: could not allocate buffer descriptors\n");
111		return -ENOMEM;
112	}
113
114	dp_mem = cpm_dpram_addr(dp_offset);
115
116	memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
117	    L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
118	if (is_con) {
119		mem_addr = kzalloc(memsz, GFP_NOWAIT);
120		dma_addr = virt_to_bus(mem_addr);
121	}
122	else
123		mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
124					      GFP_KERNEL);
125
126	if (mem_addr == NULL) {
127		cpm_dpfree(dp_offset);
128		printk(KERN_ERR
129		       "cpm_uart_cpm.c: could not allocate coherent memory\n");
130		return -ENOMEM;
131	}
132
133	pinfo->dp_addr = dp_offset;
134	pinfo->mem_addr = mem_addr;
135	pinfo->dma_addr = dma_addr;
136	pinfo->mem_size = memsz;
137
138	pinfo->rx_buf = mem_addr;
139	pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
140						       * pinfo->rx_fifosize);
141
142	pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
143	pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
144
145	return 0;
146}
147
148void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
149{
150	dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
151							  pinfo->rx_fifosize) +
152			  L1_CACHE_ALIGN(pinfo->tx_nrfifos *
153					 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
154			  pinfo->dma_addr);
155
156	cpm_dpfree(pinfo->dp_addr);
157}