Mirrors/u-boot
2
0
Fork 0
mirror of https://github.com/AsahiLinux/u-boot synced 2024-11-10 07:04:28 +00:00
Code Issues Projects Releases Packages Wiki Activity

arm: apple: rtkit: Support allocating OSLog out of SRAM in helper

Browse source 
The new OSLog region in MTP (firmware 13.3+) persists on handoff to
Linux. To avoid having to come up with some weird DART handoff or DAPF
tricks, let's just steal some of the coprocessor's dedicated SRAM. This
keeps it happy and Linux doesn't need any special handoff then.

Signed-off-by: Hector Martin <marcan@marcan.st>
This commit is contained in:
Hector Martin 2023-08-02 16:01:23 +09:00 committed by Mark Kettenis
parent b71530fc65
commit 85c637aa26
1 changed files with 49 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

50
arch/arm/mach-apple/rtkit_helper.c
View file

@ -17,12 +17,60 @@
#define REG_CPU_CTRL 0x0044
#define REG_CPU_CTRL_RUN BIT(4)
#define APPLE_RTKIT_EP_OSLOG 8
struct rtkit_helper_priv {
void *asc; /* ASC registers */
struct mbox_chan chan;
struct apple_rtkit *rtk;
bool sram_stolen;
};
static int shmem_setup(void *cookie, struct apple_rtkit_buffer *buf) {
struct udevice *dev = cookie;
struct rtkit_helper_priv *priv = dev_get_priv(dev);
if (!buf->is_mapped) {
/*
* Special case: The OSLog buffer on MTP persists on Linux handoff.
* Steal some SRAM instead of putting this in DRAM, so we don't
* have to hand off DART/DAPF mappings.
*/
if (buf->endpoint == APPLE_RTKIT_EP_OSLOG) {
if (priv->sram_stolen) {
printf("%s: Tried to map more than one OSLog buffer out of SRAM\n",
__func__);
} else {
fdt_size_t size;
fdt_addr_t addr;
addr = dev_read_addr_size_name(dev, "sram", &size);
if (addr != FDT_ADDR_T_NONE) {
buf->dva = ALIGN_DOWN(addr + size - buf->size, SZ_16K);
priv->sram_stolen = true;
return 0;
} else {
printf("%s: No SRAM, falling back to DRAM\n", __func__);
}
}
}
buf->buffer = memalign(SZ_16K, ALIGN(buf->size, SZ_16K));
if (!buf->buffer)
return -ENOMEM;
buf->dva = (u64)buf->buffer;
}
return 0;
}
static void shmem_destroy(void *cookie, struct apple_rtkit_buffer *buf) {
if (buf->buffer)
free(buf->buffer);
}
static int rtkit_helper_probe(struct udevice *dev)
{
struct rtkit_helper_priv *priv = dev_get_priv(dev);
@ -40,7 +88,7 @@ static int rtkit_helper_probe(struct udevice *dev)
ctrl = readl(priv->asc + REG_CPU_CTRL);
writel(ctrl | REG_CPU_CTRL_RUN, priv->asc + REG_CPU_CTRL);
priv->rtk = apple_rtkit_init(&priv->chan, priv, NULL, NULL);
priv->rtk = apple_rtkit_init(&priv->chan, dev, shmem_setup, shmem_destroy);
if (!priv->rtk)
return -ENOMEM;