123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138 |
- From aaa675f07e781e248fcf169ce9a917b48bc2cc9b Mon Sep 17 00:00:00 2001
- From: Brian Norris <[email protected]>
- Date: Fri, 28 Jul 2023 12:06:23 +0200
- Subject: [PATCH 3/3] firmware: qcom: scm: fix SCM cold boot address
- This effectively reverts upstream Linux commit 13e77747800e ("firmware:
- qcom: scm: Use atomic SCM for cold boot"), because Google WiFi boot
- firmwares don't support the atomic variant.
- This fixes SMP support for Google WiFi.
- Signed-off-by: Brian Norris <[email protected]>
- ---
- drivers/firmware/qcom_scm-legacy.c | 62 +++++++++++++++++++++++++-----
- drivers/firmware/qcom_scm.c | 11 ++++++
- 2 files changed, 63 insertions(+), 10 deletions(-)
- --- a/drivers/firmware/qcom_scm-legacy.c
- +++ b/drivers/firmware/qcom_scm-legacy.c
- @@ -13,6 +13,9 @@
- #include <linux/arm-smccc.h>
- #include <linux/dma-mapping.h>
-
- +#include <asm/cacheflush.h>
- +#include <asm/outercache.h>
- +
- #include "qcom_scm.h"
-
- static DEFINE_MUTEX(qcom_scm_lock);
- @@ -117,6 +120,25 @@ static void __scm_legacy_do(const struct
- } while (res->a0 == QCOM_SCM_INTERRUPTED);
- }
-
- +static void qcom_scm_inv_range(unsigned long start, unsigned long end)
- +{
- + u32 cacheline_size, ctr;
- +
- + asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
- + cacheline_size = 4 << ((ctr >> 16) & 0xf);
- +
- + start = round_down(start, cacheline_size);
- + end = round_up(end, cacheline_size);
- + outer_inv_range(start, end);
- + while (start < end) {
- + asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start)
- + : "memory");
- + start += cacheline_size;
- + }
- + dsb();
- + isb();
- +}
- +
- /**
- * scm_legacy_call() - Sends a command to the SCM and waits for the command to
- * finish processing.
- @@ -163,10 +185,16 @@ int scm_legacy_call(struct device *dev,
-
- rsp = scm_legacy_command_to_response(cmd);
-
- - cmd_phys = dma_map_single(dev, cmd, alloc_len, DMA_TO_DEVICE);
- - if (dma_mapping_error(dev, cmd_phys)) {
- - kfree(cmd);
- - return -ENOMEM;
- + if (dev) {
- + cmd_phys = dma_map_single(dev, cmd, alloc_len, DMA_TO_DEVICE);
- + if (dma_mapping_error(dev, cmd_phys)) {
- + kfree(cmd);
- + return -ENOMEM;
- + }
- + } else {
- + cmd_phys = virt_to_phys(cmd);
- + __cpuc_flush_dcache_area(cmd, alloc_len);
- + outer_flush_range(cmd_phys, cmd_phys + alloc_len);
- }
-
- smc.args[0] = 1;
- @@ -182,13 +210,26 @@ int scm_legacy_call(struct device *dev,
- goto out;
-
- do {
- - dma_sync_single_for_cpu(dev, cmd_phys + sizeof(*cmd) + cmd_len,
- - sizeof(*rsp), DMA_FROM_DEVICE);
- + if (dev) {
- + dma_sync_single_for_cpu(dev, cmd_phys + sizeof(*cmd) +
- + cmd_len, sizeof(*rsp),
- + DMA_FROM_DEVICE);
- + } else {
- + unsigned long start = (uintptr_t)cmd + sizeof(*cmd) +
- + cmd_len;
- + qcom_scm_inv_range(start, start + sizeof(*rsp));
- + }
- } while (!rsp->is_complete);
-
- - dma_sync_single_for_cpu(dev, cmd_phys + sizeof(*cmd) + cmd_len +
- - le32_to_cpu(rsp->buf_offset),
- - resp_len, DMA_FROM_DEVICE);
- + if (dev) {
- + dma_sync_single_for_cpu(dev, cmd_phys + sizeof(*cmd) + cmd_len +
- + le32_to_cpu(rsp->buf_offset),
- + resp_len, DMA_FROM_DEVICE);
- + } else {
- + unsigned long start = (uintptr_t)cmd + sizeof(*cmd) + cmd_len +
- + le32_to_cpu(rsp->buf_offset);
- + qcom_scm_inv_range(start, start + resp_len);
- + }
-
- if (res) {
- res_buf = scm_legacy_get_response_buffer(rsp);
- @@ -196,7 +237,8 @@ int scm_legacy_call(struct device *dev,
- res->result[i] = le32_to_cpu(res_buf[i]);
- }
- out:
- - dma_unmap_single(dev, cmd_phys, alloc_len, DMA_TO_DEVICE);
- + if (dev)
- + dma_unmap_single(dev, cmd_phys, alloc_len, DMA_TO_DEVICE);
- kfree(cmd);
- return ret;
- }
- --- a/drivers/firmware/qcom_scm.c
- +++ b/drivers/firmware/qcom_scm.c
- @@ -312,6 +312,17 @@ static int qcom_scm_set_boot_addr(void *
- desc.args[0] = flags;
- desc.args[1] = virt_to_phys(entry);
-
- + /*
- + * Factory firmware doesn't support the atomic variant. Non-atomic SCMs
- + * require ugly DMA invalidation support that was dropped upstream a
- + * while ago. For more info, see:
- + *
- + * [RFC] qcom_scm: IPQ4019 firmware does not support atomic API?
- + * https://lore.kernel.org/linux-arm-msm/20200913201608.GA3162100@bDebian/
- + */
- + if (of_machine_is_compatible("google,wifi"))
- + return qcom_scm_call(__scm ? __scm->dev : NULL, &desc, NULL);
- +
- return qcom_scm_call_atomic(__scm ? __scm->dev : NULL, &desc, NULL);
- }
-
|