// SPDX-License-Identifier: GPL-2.0
/*
* Procedures for drawing on the screen early on in the boot process.
*
* Benjamin Herrenschmidt <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/export.h>
#include <linux/font.h>
#include <linux/memblock.h>
#include <linux/pgtable.h>
#include <linux/of.h>
#include <asm/sections.h>
#include <asm/btext.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/udbg.h>
#define NO_SCROLL
#ifndef NO_SCROLL
static void scrollscreen(void);
#endif
#define __force_data __section(".data")
static int g_loc_X __force_data;
static int g_loc_Y __force_data;
static int g_max_loc_X __force_data;
static int g_max_loc_Y __force_data;
static int dispDeviceRowBytes __force_data;
static int dispDeviceDepth __force_data;
static int dispDeviceRect[4] __force_data;
static unsigned char *dispDeviceBase __force_data;
static unsigned char *logicalDisplayBase __force_data;
unsigned long disp_BAT[2] __initdata = {0, 0};
static int boot_text_mapped __force_data;
extern void rmci_on(void);
extern void rmci_off(void);
static inline void rmci_maybe_on(void)
{
#if defined(CONFIG_PPC_EARLY_DEBUG_BOOTX) && defined(CONFIG_PPC64)
if (!(mfmsr() & MSR_DR))
rmci_on();
#endif
}
static inline void rmci_maybe_off(void)
{
#if defined(CONFIG_PPC_EARLY_DEBUG_BOOTX) && defined(CONFIG_PPC64)
if (!(mfmsr() & MSR_DR))
rmci_off();
#endif
}
#ifdef CONFIG_PPC32
/* Calc BAT values for mapping the display and store them
* in disp_BAT. Those values are then used from head.S to map
* the display during identify_machine() and MMU_Init()
*
* The display is mapped to virtual address 0xD0000000, rather
* than 1:1, because some CHRP machines put the frame buffer
* in the region starting at 0xC0000000 (PAGE_OFFSET).
* This mapping is temporary and will disappear as soon as the
* setup done by MMU_Init() is applied.
*
* For now, we align the BAT and then map 8Mb on 601 and 16Mb
* on other PPCs. This may cause trouble if the framebuffer
* is really badly aligned, but I didn't encounter this case
* yet.
*/
void __init btext_prepare_BAT(void)
{
unsigned long vaddr = PAGE_OFFSET + 0x10000000;
unsigned long addr;
unsigned long lowbits;
addr = (unsigned long)dispDeviceBase;
if (!addr) {
boot_text_mapped = 0;
return;
}
lowbits = addr & ~0xFF000000UL;
addr &= 0xFF000000UL;
disp_BAT[0] = vaddr | (BL_16M<<2) | 2;
disp_BAT[1] = addr | (_PAGE_NO_CACHE | _PAGE_GUARDED | BPP_RW);
logicalDisplayBase = (void *) (vaddr + lowbits);
}
#endif
/* This function can be used to enable the early boot text when doing
* OF booting or within bootx init. It must be followed by a btext_unmap()
* call before the logical address becomes unusable
*/
void __init btext_setup_display(int width, int height, int depth, int pitch,
unsigned long address)
{
g_loc_X = 0;
g_loc_Y = 0;
g_max_loc_X = width / 8;
g_max_loc_Y = height / 16;
logicalDisplayBase = (unsigned char *)address;
dispDeviceBase = (unsigned char *)address;
dispDeviceRowBytes = pitch;
dispDeviceDepth = depth == 15 ? 16 : depth;
dispDeviceRect[0] = dispDeviceRect[1] = 0;
dispDeviceRect[2] = width;
dispDeviceRect[3] = height;
boot_text_mapped = 1;
}
void __init btext_unmap(void)
{
boot_text_mapped = 0;
}
/* Here's a small text engine to use during early boot
* or for debugging purposes
*
* todo:
*
* - build some kind of vgacon with it to enable early printk
* - move to a separate file
* - add a few video driver hooks to keep in sync with display
* changes.
*/
void btext_map(void)
{
unsigned long base, offset, size;
unsigned char *vbase;
/* By default, we are no longer mapped */
boot_text_mapped = 0;
if (!dispDeviceBase)
return;
base = ((unsigned long) dispDeviceBase) & 0xFFFFF000UL;
offset = ((unsigned long) dispDeviceBase) - base;
size = dispDeviceRowBytes * dispDeviceRect[3] + offset
+ dispDeviceRect[0];
vbase = ioremap_wc(base, size);
if (!vbase)
return;
logicalDisplayBase = vbase + offset;
boot_text_mapped = 1;
}
static int __init btext_initialize(struct device_node *np)
{
unsigned int width, height, depth, pitch;
unsigned long address = 0;
const u32 *prop;
prop = of_get_property(np, "linux,bootx-width", NULL);
if (prop == NULL)
prop = of_get_property(np, "width", NULL);
if (prop == NULL)
return -EINVAL;
width = *prop;
prop = of_get_property(np, "linux,bootx-height", NULL);
if (prop == NULL)
prop = of_get_property(np, "height", NULL);
if (prop == NULL)
return -EINVAL;
height = *prop;
prop = of_get_property(np, "linux,bootx-depth", NULL);
if (prop == NULL)
prop = of_get_property(np, "depth", NULL);
if (prop == NULL)
return -EINVAL;
depth = *prop;
pitch = width * ((depth + 7) / 8);
prop = of_get_property(np, "linux,bootx-linebytes", NULL);
if (prop == NULL)
prop = of_get_property(np, "linebytes", NULL);
if (prop && *prop != 0xffffffffu)
pitch = *prop;
if (pitch == 1)
pitch = 0x1000;
prop = of_get_property(np, "linux,bootx-addr", NULL);
if (prop == NULL)
prop = of_get_property(np, "address", NULL);
if (prop)
address = *prop;
/* FIXME: Add support for PCI reg properties. Right now, only
* reliable on macs
*/
if (address == 0)
return -EINVAL;
g_loc_X = 0;
g_loc_Y = 0;
g_max_loc_X = width / 8;
g_max_loc_Y = height / 16;
dispDeviceBase = (unsigned char *)address;
dispDeviceRowBytes = pitch;
dispDeviceDepth = depth == 15 ? 16 : depth;
dispDeviceRect[0] = dispDeviceRect[1] = 0;
dispDeviceRect[2] = width;
dispDeviceRect[3] = height;
btext_map();
return 0;
}
int __init btext_find_display(int allow_nonstdout)
{
struct device_node *np = of_stdout;
int rc = -ENODEV;
if (!of_node_is_type(np, "display")) {
printk("boot stdout isn't a display !\n");
np = NULL;
}
if (np)
rc = btext_initialize(np);
if (rc == 0 || !allow_nonstdout)
return rc;
for_each_node_by_type(np, "display") {
if (of_property_read_bool(np, "linux,opened")) {
printk("trying %pOF ...\n", np);
rc = btext_initialize(np);
printk("result: %d\n", rc);
}
if (rc == 0) {
of_node_put(np);
break;
}
}
return rc;
}
/* Calc the base address of a given point (x,y) */
static unsigned char * calc_base(int x, int y)
{
unsigned char *base;
base = logicalDisplayBase;
if (!base)
base = dispDeviceBase;
base += (x + dispDeviceRect[0]) * (dispDeviceDepth >> 3);
base += (y + dispDeviceRect[1]) * dispDeviceRowBytes;
return base;
}
/* Adjust the display to a new resolution */
void btext_update_display(unsigned long phys, int width, int height,
int depth, int pitch)
{
if (!dispDeviceBase)
return;
/* check it's the same frame buffer (within 256MB) */
if ((phys ^ (unsigned long)dispDeviceBase) & 0xf0000000)
return;
dispDeviceBase = (__u8 *) phys;
dispDeviceRect[0] = 0;
dispDeviceRect[1] = 0;
dispDeviceRect[2] = width;
dispDeviceRect[3] = height;
dispDeviceDepth = depth;
dispDeviceRowBytes = pitch;
if (boot_text_mapped) {
iounmap(logicalDisplayBase);
boot_text_mapped = 0;
}
btext_map();
g_loc_X = 0;
g_loc_Y = 0;
g_max_loc_X = width / 8;
g_max_loc_Y = height / 16;
}
EXPORT_SYMBOL(btext_update_display);
void __init btext_clearscreen(void)
{
unsigned int *base = (unsigned int *)calc_base(0, 0);
unsigned long width = ((dispDeviceRect[2] - dispDeviceRect[0]) *
(dispDeviceDepth >> 3)) >> 2;
int i,j;
rmci_maybe_on();
for (i=0; i<(dispDeviceRect[3] - dispDeviceRect[1]); i++)
{
unsigned int *ptr = base;
for(j=width; j; --j)
*(ptr++) = 0;
base += (dispDeviceRowBytes >> 2);
}
rmci_maybe_off();
}
void __init btext_flushscreen(void)
{
unsigned int *base = (unsigned int *)calc_base(0, 0);
unsigned long width = ((dispDeviceRect[2] - dispDeviceRect[0]) *
(dispDeviceDepth >> 3)) >> 2;
int i,j;
for (i=0; i < (dispDeviceRect[3] - dispDeviceRect[1]); i++)
{
unsigned int *ptr = base;
for(j = width; j > 0; j -= 8) {
__asm__ __volatile__ ("dcbst 0,%0" :: "r" (ptr));
ptr += 8;
}
base += (dispDeviceRowBytes >> 2);
}
__asm__ __volatile__ ("sync" ::: "memory");
}
void __init btext_flushline(void)
{
unsigned int *base = (unsigned int *)calc_base(0, g_loc_Y << 4);
unsigned long width = ((dispDeviceRect[2] - dispDeviceRect[0]) *
(dispDeviceDepth >> 3)) >> 2;
int i,j;
for (i=0; i < 16; i++)
{
unsigned int *ptr = base;
for(j = width; j > 0; j -= 8) {
__asm__ __volatile__ ("dcbst 0,%0" :: "r" (ptr));
ptr += 8;
}
base += (dispDeviceRowBytes >> 2);
}
__asm__ __volatile__ ("sync" ::: "memory");
}
#ifndef NO_SCROLL
static void scrollscreen(void)
{
unsigned int *src = (unsigned int *)calc_base(0,16);
unsigned int *dst = (unsigned int *)calc_base(0,0);
unsigned long width = ((dispDeviceRect[2] - dispDeviceRect[0]) *
(dispDeviceDepth >> 3)) >> 2;
int i,j;
rmci_maybe_on();
for (i=0; i<(dispDeviceRect[3] - dispDeviceRect[1] - 16); i++)
{
unsigned int *src_ptr = src;
unsigned int *dst_ptr = dst;
for(j=width; j; --j)
*(dst_ptr++) = *(src_ptr++);
src += (dispDeviceRowBytes >> 2);
dst += (dispDeviceRowBytes >> 2);
}
for (i=0; i<16; i++)
{
unsigned int *dst_ptr = dst;
for(j=width; j; --j)
*(dst_ptr++) = 0;
dst += (dispDeviceRowBytes >> 2);
}
rmci_maybe_off();
}
#endif /* ndef NO_SCROLL */
static unsigned int expand_bits_8[16] = {
0x00000000,
0x000000ff,
0x0000ff00,
0x0000ffff,
0x00ff0000,
0x00ff00ff,
0x00ffff00,
0x00ffffff,
0xff000000,
0xff0000ff,
0xff00ff00,
0xff00ffff,
0xffff0000,
0xffff00ff,
0xffffff00,
0xffffffff
};
static unsigned int expand_bits_16[4] = {
0x00000000,
0x0000ffff,
0xffff0000,
0xffffffff
};
static void draw_byte_32(const unsigned char *font, unsigned int *base, int rb)
{
int l, bits;
int fg = 0xFFFFFFFFUL;
int bg = 0x00000000UL;
for (l = 0; l < 16; ++l)
{
bits = *font++;
base[0] = (-(bits >> 7) & fg) ^ bg;
base[1] = (-((bits >> 6) & 1) & fg) ^ bg;
base[2] = (-((bits >> 5) & 1) & fg) ^ bg;
base[3] = (-((bits >> 4) & 1) & fg) ^ bg;
base[4] = (-((bits >> 3) & 1) & fg) ^ bg;
base[5] = (-((bits >> 2) & 1) & fg) ^ bg;
base[6] = (-((bits >> 1) & 1) & fg) ^ bg;
base[7] = (-(bits & 1) & fg) ^ bg;
base = (unsigned int *) ((char *)base + rb);
}
}
static inline void draw_byte_16(const unsigned char *font, unsigned int *base, int rb)
{
int l, bits;
int fg = 0xFFFFFFFFUL;
int bg = 0x00000000UL;
unsigned int *eb = (int *)expand_bits_16;
for (l = 0; l < 16; ++l)
{
bits = *font++;
base[0] = (eb[bits >> 6] & fg) ^ bg;
base[1] = (eb[(bits >> 4) & 3] & fg) ^ bg;
base[2] = (eb[(bits >> 2) & 3] & fg) ^ bg;
base[3] = (eb[bits & 3] & fg) ^ bg;
base = (unsigned int *) ((char *)base + rb);
}
}
static inline void draw_byte_8(const unsigned char *font, unsigned int *base, int rb)
{
int l, bits;
int fg = 0x0F0F0F0FUL;
int bg = 0x00000000UL;
unsigned int *eb = (int *)expand_bits_8;
for (l = 0; l < 16; ++l)
{
bits = *font++;
base[0] = (eb[bits >> 4] & fg) ^ bg;
base[1] = (eb[bits & 0xf] & fg) ^ bg;
base = (unsigned int *) ((char *)base + rb);
}
}
static noinline void draw_byte(unsigned char c, long locX, long locY)
{
unsigned char *base = calc_base(locX << 3, locY << 4);
unsigned int font_index = c * 16;
const unsigned char *font = font_sun_8x16.data + font_index;
int rb = dispDeviceRowBytes;
rmci_maybe_on();
switch(dispDeviceDepth) {
case 24:
case 32:
draw_byte_32(font, (unsigned int *)base, rb);
break;
case 15:
case 16:
draw_byte_16(font, (unsigned int *)base, rb);
break;
case 8:
draw_byte_8(font, (unsigned int *)base, rb);
break;
}
rmci_maybe_off();
}
void btext_drawchar(char c)
{
int cline = 0;
#ifdef NO_SCROLL
int x;
#endif
if (!boot_text_mapped)
return;
switch (c) {
case '\b':
if (g_loc_X > 0)
--g_loc_X;
break;
case '\t':
g_loc_X = (g_loc_X & -8) + 8;
break;
case '\r':
g_loc_X = 0;
break;
case '\n':
g_loc_X = 0;
g_loc_Y++;
cline = 1;
break;
default:
draw_byte(c, g_loc_X++, g_loc_Y);
}
if (g_loc_X >= g_max_loc_X) {
g_loc_X = 0;
g_loc_Y++;
cline = 1;
}
#ifndef NO_SCROLL
while (g_loc_Y >= g_max_loc_Y) {
scrollscreen();
g_loc_Y--;
}
#else
/* wrap around from bottom to top of screen so we don't
waste time scrolling each line. -- paulus. */
if (g_loc_Y >= g_max_loc_Y)
g_loc_Y = 0;
if (cline) {
for (x = 0; x < g_max_loc_X; ++x)
draw_byte(' ', x, g_loc_Y);
}
#endif
}
void btext_drawstring(const char *c)
{
if (!boot_text_mapped)
return;
while (*c)
btext_drawchar(*c++);
}
void __init btext_drawtext(const char *c, unsigned int len)
{
if (!boot_text_mapped)
return;
while (len--)
btext_drawchar(*c++);
}
void __init btext_drawhex(unsigned long v)
{
if (!boot_text_mapped)
return;
#ifdef CONFIG_PPC64
btext_drawchar(hex_asc_hi(v >> 56));
btext_drawchar(hex_asc_lo(v >> 56));
btext_drawchar(hex_asc_hi(v >> 48));
btext_drawchar(hex_asc_lo(v >> 48));
btext_drawchar(hex_asc_hi(v >> 40));
btext_drawchar(hex_asc_lo(v >> 40));
btext_drawchar(hex_asc_hi(v >> 32));
btext_drawchar(hex_asc_lo(v >> 32));
#endif
btext_drawchar(hex_asc_hi(v >> 24));
btext_drawchar(hex_asc_lo(v >> 24));
btext_drawchar(hex_asc_hi(v >> 16));
btext_drawchar(hex_asc_lo(v >> 16));
btext_drawchar(hex_asc_hi(v >> 8));
btext_drawchar(hex_asc_lo(v >> 8));
btext_drawchar(hex_asc_hi(v));
btext_drawchar(hex_asc_lo(v));
btext_drawchar(' ');
}
void __init udbg_init_btext(void)
{
/* If btext is enabled, we might have a BAT setup for early display,
* thus we do enable some very basic udbg output
*/
udbg_putc = btext_drawchar;
}
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