[Skiboot] [PATCH 3/3] ibm-fsp: Use finalise_dt() for DT fixups

[Oliver O'Halloran]

>From Gautham's patch to fix pstates_init() that this was based on:

> On FSP based systems (particularly POWER8), we perform
> occ_pstates_init() late in the boot to allow OCC to be loaded. Hence
> this was being performed in platform.exit(). occ_pstates_init() would
> add pstate information into the device-tree.
>
> A recent commit 9fc0c1287ada ("Move FSP specific op-panel calls to
> platform.exit()") moved the invocation of platform.exit() after the
> creation of device-tree blob. As a result, on FSP based systems, we
> don't have the pstate information in the device-tree, and thus the
> Kernel is unable to perform frequency scaling.
>
> Fix this by moving occ_pstates_init() out of ibm_fsp_exit() and call
> it before the creation of the device-tree blob.

The same patch also broke fast-reboot on ZZ. Without this patch applied
we get the following assert() fail when fast rebooting:

[ 1153.398889405,5] CUPD: Waiting read marker LID and in flight parsm completion...
[ 1153.398892228,3] Duplicate property "mi-version" in node /ibm,opal/firmware
[ 1153.398894036,0] Aborting!
CPU 0054 Backtrace:
 S: 0000000031ea39b0 R: 0000000030013828   .backtrace+0x34
 S: 0000000031ea3a70 R: 000000003001b268   ._abort+0x4c
 S: 0000000031ea3af0 R: 0000000030027788   .new_property+0x80
 S: 0000000031ea3b80 R: 00000000300278d0   .dt_add_property+0xa8
 S: 0000000031ea3c10 R: 0000000030081a98   .fsp_code_update_wait_vpd+0x19c
 S: 0000000031ea3d10 R: 000000003008ff98   .ibm_fsp_exit+0x1c
 S: 0000000031ea3d80 R: 0000000030014864   .load_and_boot_kernel+0xb14
 S: 0000000031ea3e60 R: 000000003002685c   .fast_reboot_entry+0x38c
 S: 0000000031ea3f00 R: 0000000030002988   reset_fast_reboot_wakeup+0x40

This happens because fsp_code_update_wait_vpd(true) adds some properties
to the DT so moving it to finalise_dt fixes that crash too.

Cc: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
Cc: Gautham R. Shenoy <ego at linux.vnet.ibm.com>
Cc: Vaidyanathan Srinivasan <svaidy at linux.ibm.com>
Fixes: 9fc0c1287ada ("Move FSP specific op-panel calls to platform.exit()")
Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
---
 platforms/ibm-fsp/common.c  | 17 +++++++++++------
 platforms/ibm-fsp/firenze.c |  1 +
 platforms/ibm-fsp/ibm-fsp.h |  1 +
 platforms/ibm-fsp/zz.c      |  1 +
 4 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/platforms/ibm-fsp/common.c b/platforms/ibm-fsp/common.c
index 7f7a1f246206..6f9d57a8fb6b 100644
--- a/platforms/ibm-fsp/common.c
+++ b/platforms/ibm-fsp/common.c
@@ -174,8 +174,11 @@ void ibm_fsp_init(void)
 	preload_io_vpd();
 }
 
-void ibm_fsp_exit(void)
+void ibm_fsp_finalise_dt(bool is_reboot)
 {
+	if (is_reboot)
+		return;
+
 	/*
 	 * LED related SPCN commands might take a while to
 	 * complete. Call this as late as possible to
@@ -183,18 +186,20 @@ void ibm_fsp_exit(void)
 	 */
 	create_led_device_nodes();
 
-	/* Wait for FW VPD data read to complete */
-	fsp_code_update_wait_vpd(true);
-
 	/*
 	 * OCC takes few secs to boot.  Call this as late as
 	 * as possible to avoid delay.
 	 */
-	if (fsp_present())
-		occ_pstates_init();
+	occ_pstates_init();
+
+	/* Wait for FW VPD data read to complete */
+	fsp_code_update_wait_vpd(true);
 
 	fsp_console_select_stdout();
+}
 
+void ibm_fsp_exit(void)
+{
 	op_panel_disable_src_echo();
 
 	/* Clear SRCs on the op-panel when Linux starts */
diff --git a/platforms/ibm-fsp/firenze.c b/platforms/ibm-fsp/firenze.c
index 232833480f75..db18e2ff4eba 100644
--- a/platforms/ibm-fsp/firenze.c
+++ b/platforms/ibm-fsp/firenze.c
@@ -214,6 +214,7 @@ DECLARE_PLATFORM(firenze) = {
 	.probe			= firenze_probe,
 	.init			= firenze_init,
 	.fast_reboot_init	= fsp_console_reset,
+	.finalise_dt		= ibm_fsp_finalise_dt,
 	.exit			= ibm_fsp_exit,
 	.cec_power_down		= ibm_fsp_cec_power_down,
 	.cec_reboot		= ibm_fsp_cec_reboot,
diff --git a/platforms/ibm-fsp/ibm-fsp.h b/platforms/ibm-fsp/ibm-fsp.h
index dc3969ec688d..c055d4a3e6f9 100644
--- a/platforms/ibm-fsp/ibm-fsp.h
+++ b/platforms/ibm-fsp/ibm-fsp.h
@@ -20,6 +20,7 @@
 
 extern void ibm_fsp_init(void);
 extern void ibm_fsp_exit(void);
+void ibm_fsp_finalise_dt(bool is_reboot);
 
 extern int64_t ibm_fsp_cec_power_down(uint64_t request);
 extern int64_t ibm_fsp_cec_reboot(void);
diff --git a/platforms/ibm-fsp/zz.c b/platforms/ibm-fsp/zz.c
index f44c618c0ec1..e369f8d1fc5b 100644
--- a/platforms/ibm-fsp/zz.c
+++ b/platforms/ibm-fsp/zz.c
@@ -79,6 +79,7 @@ DECLARE_PLATFORM(zz) = {
 	.probe			= zz_probe,
 	.init			= zz_init,
 	.fast_reboot_init	= fsp_console_reset,
+	.finalise_dt		= ibm_fsp_finalise_dt,
 	.exit			= ibm_fsp_exit,
 	.cec_power_down		= ibm_fsp_cec_power_down,
 	.cec_reboot		= ibm_fsp_cec_reboot,
-- 
2.21.0