Re: [PATCH 4/6] mips: bmips: setup: make CBR address configurable

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 5/3/24 06:54, Christian Marangi wrote:
Add support to provide CBR address from DT to handle broken
SoC/Bootloader that doesn't correctly init it. This permits to use the
RAC flush even in these condition.

To provide a CBR address from DT, the property "mips-cbr-reg" needs to
be set in the "cpus" node. On DT init, this property presence will be
checked and will set the bmips_cbr_addr value accordingly. Also
bmips_rac_flush_disable will be set to false as RAC flush can be
correctly supported.

The CBR address from DT will be applied only if the CBR address from the
registers is 0, if the CBR address from the registers is not 0 and
is not equal to the one set in DT (if provided) a WARN is printed.

To ALWAYS overwrite the CBR address the additional property
"mips-broken-cbr-reg" needs to be set.

Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
---
  arch/mips/bmips/setup.c | 30 +++++++++++++++++++++++++++---
  1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/arch/mips/bmips/setup.c b/arch/mips/bmips/setup.c
index 18561d426f89..bef84677248e 100644
--- a/arch/mips/bmips/setup.c
+++ b/arch/mips/bmips/setup.c
@@ -34,7 +34,11 @@
  #define REG_BCM6328_OTP		((void __iomem *)CKSEG1ADDR(0x1000062c))
  #define BCM6328_TP1_DISABLED	BIT(9)
-/* CBR addr doesn't change and we can cache it */
+/*
+ * CBR addr doesn't change and we can cache it.
+ * For broken SoC/Bootloader CBR addr might also be provided via DT
+ * with "mips-cbr-reg" in the "cpus" node.
+ */
  void __iomem *bmips_cbr_addr;
  extern bool bmips_rac_flush_disable;
@@ -212,8 +216,28 @@ void __init device_tree_init(void) /* Disable SMP boot unless both CPUs are listed in DT and !disabled */
  	np = of_find_node_by_name(NULL, "cpus");
-	if (np && of_get_available_child_count(np) <= 1)
-		bmips_smp_enabled = 0;
+	if (np) {

Please reduce the indentation with early return/gotos. There might also be a need to do some validation that the CBR is at least outside of the DRAM window, that is we cannot blindly trust the DT to have gotten the CBR right IMHO.
--
Florian

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature


[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux