A memory region for CEU video buffer has to be reserved during machine
initialization.
Originally, it was allocated through DMA API helpers and stored in the
second IORESOURCE_MEM entry, to be later remapped by the CEU driver with
a call to 'dma_declare_coherent_memory()'
As Linux does not allow anymore to remap system RAM regions with
'memremap' function, sh_mobile_ceu driver fails when trying to remap the
memory area:
WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
&offset, (unsigned long) size)
from 'memremap()' function in kernel/memremap.c
To avoid hitting that WARN_ONCE() and have memory successfully remapped,
reserve a region using '.mv_mem_reserve' member of SH's 'struct
sh_machine_vector' to make sure memory is reserved early enough, and
removed from the available system RAM.
This is similar to what happens on ARM architecture with
'arm_memblock_steal()' function.
Suggested-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo+rene...@jmondi.org>
---
arch/sh/boards/mach-migor/setup.c | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)
diff --git a/arch/sh/boards/mach-migor/setup.c
b/arch/sh/boards/mach-migor/setup.c
index 0bcbe58..080627c 100644
--- a/arch/sh/boards/mach-migor/setup.c
+++ b/arch/sh/boards/mach-migor/setup.c
@@ -12,6 +12,7 @@
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/input/sh_keysc.h>
+#include <linux/memblock.h>
#include <linux/mmc/host.h>
#include <linux/mtd/physmap.h>
#include <linux/mfd/tmio.h>
@@ -45,6 +46,9 @@
* 0x18000000 8GB 8 NAND Flash (K9K8G08U0A)
*/
+#define CEU_BUFFER_MEMORY_SIZE (4 << 20)
+static phys_addr_t ceu_dma_membase;
+
static struct smc91x_platdata smc91x_info = {
.flags = SMC91X_USE_16BIT | SMC91X_NOWAIT,
};
@@ -501,6 +505,8 @@ extern char migor_sdram_leave_end;
static int __init migor_devices_setup(void)
{
+ struct resource *r = &migor_ceu_device.resource[2];
+
/* register board specific self-refresh code */
sh_mobile_register_self_refresh(SUSP_SH_STANDBY | SUSP_SH_SF,
&migor_sdram_enter_start,
@@ -632,8 +638,6 @@ static int __init migor_devices_setup(void)
#endif
__raw_writew(__raw_readw(PORT_MSELCRB) | 0x2000, PORT_MSELCRB); /*
D15->D8 */
- platform_resource_setup_memory(&migor_ceu_device, "ceu", 4 << 20);
-
/* SIU: Port B */
gpio_request(GPIO_FN_SIUBOLR, NULL);
gpio_request(GPIO_FN_SIUBOBT, NULL);
@@ -647,6 +651,12 @@ static int __init migor_devices_setup(void)
*/
__raw_writew(__raw_readw(PORT_MSELCRA) | 1, PORT_MSELCRA);
+ /* Setup additional memory resources for Migo-R */
+ r->flags = IORESOURCE_MEM;
+ r->start = ceu_dma_membase;
+ r->end = r->start + CEU_BUFFER_MEMORY_SIZE - 1;
+ r->name = "ceu";
+
i2c_register_board_info(0, migor_i2c_devices,
ARRAY_SIZE(migor_i2c_devices));
@@ -665,10 +675,24 @@ static int migor_mode_pins(void)
return MODE_PIN0 | MODE_PIN1 | MODE_PIN5;
}
+/* Reserve a portion of memory for CEU buffers */
+static void __init migor_mv_mem_reserve(void)
+{
+ phys_addr_t phys;
+ phys_addr_t size = CEU_BUFFER_MEMORY_SIZE;
+
+ phys = memblock_alloc_base(size, PAGE_SIZE, MEMBLOCK_ALLOC_ANYWHERE);
+ memblock_free(phys, size);
+ memblock_remove(phys, size);
+
+ ceu_dma_membase = phys;
+}
+
/*
* The Machine Vector
*/
static struct sh_machine_vector mv_migor __initmv = {
.mv_name = "Migo-R",
.mv_mode_pins = migor_mode_pins,
+ .mv_mem_reserve = migor_mv_mem_reserve,
};
--
2.7.4
