Blackfin arch: rewrite cplbinfo to use seq files

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

arch/blackfin/kernel/cplbinfo.c

@@ -5,189 +5,255 @@
  * Licensed under the GPL-2 or later.
  */
 
+#include <linux/ctype.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <linux/uaccess.h>
 
 #include <asm/cplbinit.h>
 #include <asm/blackfin.h>
 
-typedef enum { ICPLB, DCPLB } cplb_type;
-
-static char page_strtbl[][3] = { "1K", "4K", "1M", "4M" };
+static char const page_strtbl[][3] = { "1K", "4K", "1M", "4M" };
 #define page(flags)    (((flags) & 0x30000) >> 16)
 #define strpage(flags) page_strtbl[page(flags)]
 
 #ifdef CONFIG_MPU
 
-static char *cplb_print_entry(char *buf, cplb_type type, unsigned int cpu)
-{
+struct cplbinfo_data {
+	loff_t pos;
+	char cplb_type;
+	u32 mem_control;
 	struct cplb_entry *tbl;
 	int switched;
-	int i;
+};
 
-	if (type == ICPLB) {
-		tbl = icplb_tbl[cpu];
-		switched = first_switched_icplb;
-	} else {
-		tbl = dcplb_tbl[cpu];
-		switched = first_switched_dcplb;
-	}
+static void cplbinfo_print_header(struct seq_file *m)
+{
+	seq_printf(m, "Index\tAddress\t\tData\tSize\tU/RD\tU/WR\tS/WR\tSwitch\n");
+}
+
+static int cplbinfo_nomore(struct cplbinfo_data *cdata)
+{
+	return cdata->pos >= MAX_CPLBS;
+}
 
-	buf += sprintf(buf, "Index\tAddress\t\tData\tSize\tU/RD\tU/WR\tS/WR\tSwitch\n");
-	for (i = 0; i < MAX_CPLBS; ++i) {
-		unsigned long data = tbl[i].data;
-		unsigned long addr = tbl[i].addr;
+static int cplbinfo_show(struct seq_file *m, void *p)
+{
+	struct cplbinfo_data *cdata;
+	unsigned long data, addr;
+	loff_t pos;
 
-		if (!(data & CPLB_VALID))
-			continue;
+	cdata = p;
+	pos = cdata->pos;
+	addr = cdata->tbl[pos].addr;
+	data = cdata->tbl[pos].data;
 
-		buf += sprintf(buf,
+	seq_printf(m,
 		"%d\t0x%08lx\t%05lx\t%s\t%c\t%c\t%c\t%c\n",
-			i, addr, data, strpage(data),
+		(int)pos, addr, data, strpage(data),
 		(data & CPLB_USER_RD) ? 'Y' : 'N',
 		(data & CPLB_USER_WR) ? 'Y' : 'N',
 		(data & CPLB_SUPV_WR) ? 'Y' : 'N',
-			i < switched ? 'N' : 'Y');
-	}
-	buf += sprintf(buf, "\n");
+		pos < cdata->switched ? 'N' : 'Y');
 
-	return buf;
+	return 0;
+}
+
+static void cplbinfo_seq_init(struct cplbinfo_data *cdata, unsigned int cpu)
+{
+	if (cdata->cplb_type == 'I') {
+		cdata->mem_control = bfin_read_IMEM_CONTROL();
+		cdata->tbl = icplb_tbl[cpu];
+		cdata->switched = first_switched_icplb;
+	} else {
+		cdata->mem_control = bfin_read_DMEM_CONTROL();
+		cdata->tbl = dcplb_tbl[cpu];
+		cdata->switched = first_switched_dcplb;
+	}
 }
 
 #else
 
+struct cplbinfo_data {
+	loff_t pos;
+	char cplb_type;
+	u32 mem_control;
+	unsigned long *pdt_tables, *pdt_swapcount;
+	unsigned long cplb_addr, cplb_data;
+};
+
 extern int page_size_table[];
 
-static int cplb_find_entry(unsigned long *cplb_addr,
-			   unsigned long *cplb_data, unsigned long addr,
-			   unsigned long data)
+static int cplb_find_entry(unsigned long addr_tbl, unsigned long data_tbl,
+                           unsigned long addr_find, unsigned long data_find)
 {
 	int i;
 
-	for (i = 0; i < 16; ++i)
-		if (addr >= cplb_addr[i] &&
-		    addr < cplb_addr[i] + page_size_table[page(cplb_data[i])] &&
-		    cplb_data[i] == data)
+	for (i = 0; i < 16; ++i) {
+		unsigned long cplb_addr = bfin_read32(addr_tbl + i * 4);
+		unsigned long cplb_data = bfin_read32(data_tbl + i * 4);
+		if (addr_find >= cplb_addr &&
+		    addr_find < cplb_addr + page_size_table[page(cplb_data)] &&
+		    cplb_data == data_find)
 			return i;
+	}
 
 	return -1;
 }
 
-static char *cplb_print_entry(char *buf, cplb_type type, unsigned int cpu)
+static void cplbinfo_print_header(struct seq_file *m)
 {
-	unsigned long *p_addr, *p_data, *p_icount, *p_ocount;
-	unsigned long *cplb_addr, *cplb_data;
-	int entry = 0, used_cplb = 0;
-
-	if (type == ICPLB) {
-		p_addr = ipdt_tables[cpu];
-		p_data = ipdt_tables[cpu] + 1;
-		p_icount = ipdt_swapcount_tables[cpu];
-		p_ocount = ipdt_swapcount_tables[cpu] + 1;
-		cplb_addr = (unsigned long *)ICPLB_ADDR0;
-		cplb_data = (unsigned long *)ICPLB_DATA0;
-	} else {
-		p_addr = dpdt_tables[cpu];
-		p_data = dpdt_tables[cpu] + 1;
-		p_icount = dpdt_swapcount_tables[cpu];
-		p_ocount = dpdt_swapcount_tables[cpu] + 1;
-		cplb_addr = (unsigned long *)DCPLB_ADDR0;
-		cplb_data = (unsigned long *)DCPLB_DATA0;
-	}
-
-	buf += sprintf(buf, "Address\t\tData\tSize\tValid\tLocked\tSwapin\tiCount\toCount\n");
+	seq_printf(m, "Address\t\tData\tSize\tValid\tLocked\tSwapin\tiCount\toCount\n");
+}
 
-	while (*p_addr != 0xffffffff) {
-		entry = cplb_find_entry(cplb_addr, cplb_data, *p_addr, *p_data);
-		if (entry >= 0)
-			used_cplb |= 1 << entry;
+static int cplbinfo_nomore(struct cplbinfo_data *cdata)
+{
+	return cdata->pdt_tables[cdata->pos * 2] == 0xffffffff;
+}
 
-		buf += sprintf(buf,
+static int cplbinfo_show(struct seq_file *m, void *p)
+{
+	struct cplbinfo_data *cdata;
+	unsigned long data, addr;
+	int entry;
+	loff_t pos;
+
+	cdata = p;
+	pos = cdata->pos * 2;
+	addr = cdata->pdt_tables[pos];
+	data = cdata->pdt_tables[pos + 1];
+	entry = cplb_find_entry(cdata->cplb_addr, cdata->cplb_data, addr, data);
+
+	seq_printf(m,
 		"0x%08lx\t0x%05lx\t%s\t%c\t%c\t%2d\t%ld\t%ld\n",
-			*p_addr, *p_data, strpage(*p_data),
-			(*p_data & CPLB_VALID) ? 'Y' : 'N',
-			(*p_data & CPLB_LOCK) ? 'Y' : 'N', entry, *p_icount,
-			*p_ocount);
-
-		p_addr += 2;
-		p_data += 2;
-		p_icount += 2;
-		p_ocount += 2;
-	}
+		addr, data, strpage(data),
+		(data & CPLB_VALID) ? 'Y' : 'N',
+		(data & CPLB_LOCK) ? 'Y' : 'N', entry,
+		cdata->pdt_swapcount[pos],
+		cdata->pdt_swapcount[pos + 1]);
 
-	if (used_cplb != 0xffff) {
-		buf += sprintf(buf, "Unused/mismatched CPLBs:\n");
-
-		for (entry = 0; entry < 16; ++entry)
-			if (0 == ((1 << entry) & used_cplb)) {
-				int flags = cplb_data[entry];
-				buf += sprintf(buf,
-					"%2d: 0x%08lx\t0x%05x\t%s\t%c\t%c\n",
-					entry, cplb_addr[entry], flags, strpage(flags),
-					(flags & CPLB_VALID) ? 'Y' : 'N',
-					(flags & CPLB_LOCK) ? 'Y' : 'N');
-			}
+	return 0;
+}
+
+static void cplbinfo_seq_init(struct cplbinfo_data *cdata, unsigned int cpu)
+{
+	if (cdata->cplb_type == 'I') {
+		cdata->mem_control = bfin_read_IMEM_CONTROL();
+		cdata->pdt_tables = ipdt_tables[cpu];
+		cdata->pdt_swapcount = ipdt_swapcount_tables[cpu];
+		cdata->cplb_addr = ICPLB_ADDR0;
+		cdata->cplb_data = ICPLB_DATA0;
+	} else {
+		cdata->mem_control = bfin_read_DMEM_CONTROL();
+		cdata->pdt_tables = dpdt_tables[cpu];
+		cdata->pdt_swapcount = dpdt_swapcount_tables[cpu];
+		cdata->cplb_addr = DCPLB_ADDR0;
+		cdata->cplb_data = DCPLB_DATA0;
 	}
+}
 
-	buf += sprintf(buf, "\n");
+#endif
 
-	return buf;
+static void *cplbinfo_start(struct seq_file *m, loff_t *pos)
+{
+	struct cplbinfo_data *cdata = m->private;
+
+	if (!*pos) {
+		seq_printf(m, "%cCPLBs are %sabled: 0x%x\n", cdata->cplb_type,
+			(cdata->mem_control & ENDCPLB ? "en" : "dis"),
+			cdata->mem_control);
+		cplbinfo_print_header(m);
+	} else if (cplbinfo_nomore(cdata))
+		return NULL;
+
+	get_cpu();
+	return cdata;
 }
 
-#endif
+static void *cplbinfo_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	struct cplbinfo_data *cdata = p;
+	cdata->pos = ++(*pos);
+	if (cplbinfo_nomore(cdata))
+		return NULL;
+	else
+		return cdata;
+}
 
-static int cplbinfo_proc_output(char *buf, void *data)
+static void cplbinfo_stop(struct seq_file *m, void *p)
 {
-	unsigned int cpu = (unsigned int)data;
-	char *p = buf;
-
-	if (bfin_read_IMEM_CONTROL() & ENICPLB) {
-		p += sprintf(p, "Instruction CPLB entry:\n");
-		p = cplb_print_entry(p, ICPLB, cpu);
-	} else
-		p += sprintf(p, "Instruction CPLB is disabled.\n\n");
-
-	if (bfin_read_DMEM_CONTROL() & ENDCPLB) {
-		p += sprintf(p, "Data CPLB entry:\n");
-		p = cplb_print_entry(p, DCPLB, cpu);
-	} else
-		p += sprintf(p, "Data CPLB is disabled.\n\n");
-
-	return p - buf;
+	put_cpu();
 }
 
-static int cplbinfo_read_proc(char *page, char **start, off_t off,
-			      int count, int *eof, void *data)
+static const struct seq_operations cplbinfo_sops = {
+	.start = cplbinfo_start,
+	.next  = cplbinfo_next,
+	.stop  = cplbinfo_stop,
+	.show  = cplbinfo_show,
+};
+
+static int cplbinfo_open(struct inode *inode, struct file *file)
 {
-	int len = cplbinfo_proc_output(page, data);
-	if (len <= off + count)
-		*eof = 1;
-	*start = page + off;
-	len -= off;
-	return max(min(len, count), 0);
+	char buf[256], *path, *p;
+	unsigned int cpu;
+	char *s_cpu, *s_cplb;
+	int ret;
+	struct seq_file *m;
+	struct cplbinfo_data *cdata;
+
+	path = d_path(&file->f_path, buf, sizeof(buf));
+	if (IS_ERR(path))
+		return PTR_ERR(path);
+	s_cpu = strstr(path, "/cpu");
+	s_cplb = strrchr(path, '/');
+	if (!s_cpu || !s_cplb)
+		return -EINVAL;
+
+	cpu = simple_strtoul(s_cpu + 4, &p, 10);
+	if (!cpu_online(cpu))
+		return -ENODEV;
+
+	ret = seq_open_private(file, &cplbinfo_sops, sizeof(*cdata));
+	if (ret)
+		return ret;
+	m = file->private_data;
+	cdata = m->private;
+
+	cdata->pos = 0;
+	cdata->cplb_type = toupper(s_cplb[1]);
+	cplbinfo_seq_init(cdata, cpu);
+
+	return 0;
 }
 
+static const struct file_operations cplbinfo_fops = {
+	.open    = cplbinfo_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private,
+};
+
 static int __init cplbinfo_init(void)
 {
-	struct proc_dir_entry *parent, *entry;
+	struct proc_dir_entry *cplb_dir, *cpu_dir;
+	char buf[10];
 	unsigned int cpu;
-	unsigned char str[10];
 
-	parent = proc_mkdir("cplbinfo", NULL);
-	if (!parent)
+	cplb_dir = proc_mkdir("cplbinfo", NULL);
+	if (!cplb_dir)
 		return -ENOMEM;
 
-	for_each_online_cpu(cpu) {
-		sprintf(str, "cpu%u", cpu);
-		entry = create_proc_entry(str, 0, parent);
-		if (!entry)
+	for_each_possible_cpu(cpu) {
+		sprintf(buf, "cpu%i", cpu);
+		cpu_dir = proc_mkdir(buf, cplb_dir);
+		if (!cpu_dir)
 			return -ENOMEM;
 
-		entry->read_proc = cplbinfo_read_proc;
-		entry->data = (void *)cpu;
+		proc_create("icplb", S_IRUGO, cpu_dir, &cplbinfo_fops);
+		proc_create("dcplb", S_IRUGO, cpu_dir, &cplbinfo_fops);
 	}
 
 	return 0;