Two omap fixes for v4.18-rc cycle

Turns out the recent patches for ARM branch predictor hardening are
 not working on omap5 and dra7 as planned because the secondary CPU
 is parked to the bootrom code. We can't configure it in the bootloader.
 So we must enable invalidates of BTB for omap5 and dra7 secondary
 core in the kernel.
 
 And there's a fix for reserved register access for am3517. The
 usb otg module on am3517 is not the same as for other omap3.
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCAAvFiEEkgNvrZJU/QSQYIcQG9Q+yVyrpXMFAltImsMRHHRvbnlAYXRv
 bWlkZS5jb20ACgkQG9Q+yVyrpXOqNw/7BAD1n1sS2Sq+6QdYLNvWkxlstcarDf29
 5jolIQJCaa60WF9C1oTaoy59+UcaiLyk2dWYGgi1ZDce4ihhyIhQUFscHab2Zh0B
 o4zGXuTnTRBRiCKSI3ue8MTLTpYkuSmoTfWJu3ACEmR0co9J9sHztYz4yd1vj7E6
 tWvYLsYv7av4URBNaL4ieeUAZrailRQ3l5vg/+fJ7Xhk1+Ue3bQUmb3DDtypD1Ub
 OVFVtHGJdxDLaKJ0fhYPIoZYLhIe9BSuxboGrmh/vpyn6kuZ2Q/iWFSyX4kfveoH
 uEPWzJ6xMe0XNsxyuZ9bYO1rsBrOxXGzZNrgmiLI+GQ4uTK+e68vHPOimtWsNVb1
 hMpr8eTiyEUR/lhtMVoizGVPiNnJfhfnbIrUx5g80mAiwogIp9p3IEYHQD2zh4Ly
 susyjPV9TWoesS1RUrJz2N59qLgSPdOYhmfpaYmc31mVEXu+TiDDxyrUNz++or10
 UfJIo/MGDoIWbuRPMRfQEzdJqv13D0FuVbXkgaNWIvAnuDlqQx27dQLDRPepZqS3
 kHeOwrxf4h6NrlbCAdF4wn34WLbuMIdpp6rxstGsPi9TVR3PytetBtMlqMkJnfd6
 Yg3WcbN695ZNEod1tJhj5E8yUAdYtYPFKSX0egF4z/HrZ4NrjG/JB0gSXXSeS2Q7
 X7ecetNHONs=
 =Wci4
 -----END PGP SIGNATURE-----

Merge tag 'omap-for-v4.18/fixes-rc4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Two omap fixes for v4.18-rc cycle

Turns out the recent patches for ARM branch predictor hardening are
not working on omap5 and dra7 as planned because the secondary CPU
is parked to the bootrom code. We can't configure it in the bootloader.
So we must enable invalidates of BTB for omap5 and dra7 secondary
core in the kernel.

And there's a fix for reserved register access for am3517. The
usb otg module on am3517 is not the same as for other omap3.

* tag 'omap-for-v4.18/fixes-rc4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: am3517.dtsi:  Disable reference to OMAP3 OTG controller
  ARM: DRA7/OMAP5: Enable ACTLR[0] (Enable invalidates of BTB) for secondary cores

Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Olof Johansson 2018-07-14 15:14:02 -07:00
commit 13e66ceea1
2 changed files with 46 additions and 0 deletions

View File

@ -91,6 +91,11 @@
};
};
/* Table Table 5-79 of the TRM shows 480ab000 is reserved */
&usb_otg_hs {
status = "disabled";
};
&iva {
status = "disabled";
};

View File

@ -109,6 +109,45 @@ void omap5_erratum_workaround_801819(void)
static inline void omap5_erratum_workaround_801819(void) { }
#endif
#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
/*
* Configure ACR and enable ACTLR[0] (Enable invalidates of BTB with
* ICIALLU) to activate the workaround for secondary Core.
* NOTE: it is assumed that the primary core's configuration is done
* by the boot loader (kernel will detect a misconfiguration and complain
* if this is not done).
*
* In General Purpose(GP) devices, ACR bit settings can only be done
* by ROM code in "secure world" using the smc call and there is no
* option to update the "firmware" on such devices. This also works for
* High security(HS) devices, as a backup option in case the
* "update" is not done in the "security firmware".
*/
static void omap5_secondary_harden_predictor(void)
{
u32 acr, acr_mask;
asm volatile ("mrc p15, 0, %0, c1, c0, 1" : "=r" (acr));
/*
* ACTLR[0] (Enable invalidates of BTB with ICIALLU)
*/
acr_mask = BIT(0);
/* Do we already have it done.. if yes, skip expensive smc */
if ((acr & acr_mask) == acr_mask)
return;
acr |= acr_mask;
omap_smc1(OMAP5_DRA7_MON_SET_ACR_INDEX, acr);
pr_debug("%s: ARM ACR setup for CVE_2017_5715 applied on CPU%d\n",
__func__, smp_processor_id());
}
#else
static inline void omap5_secondary_harden_predictor(void) { }
#endif
static void omap4_secondary_init(unsigned int cpu)
{
/*
@ -131,6 +170,8 @@ static void omap4_secondary_init(unsigned int cpu)
set_cntfreq();
/* Configure ACR to disable streaming WA for 801819 */
omap5_erratum_workaround_801819();
/* Enable ACR to allow for ICUALLU workaround */
omap5_secondary_harden_predictor();
}
/*