Four All Ordinaries Index (ASX: XAO) shares just earned upgrades from top brokers. One ASX All Ords share is a major Aussie bank.

The second is an infrastructure maintenance services provider.

The third provides telecommunications and network services.

And the fourth ASX stock getting a broker upgrade produces fertilisers, explosives and chemicals.

A nicely diversified mix!

Here's what we know.

(Broker data courtesy of The Australian.)

Four ASX All Ords shares with upgraded outlooks

The first ASX All Ords share that just got a broker upgrade is Bank of Queensland Ltd (ASX: BOQ).

The Bank of Queensland share price is up 3.6% today at $6.92 and up more than 25% over the past 12 months. Bank of Queensland shares also trade on a fully franked trailing dividend yield of 4.9%.

While Macquarie believes shares may be overvalued at current levels, the broker raised its target price for the Bank of Queensland share price by 10% to $5.50.

The second ASX All Ords share that just got a broker upgrade is Incitec Pivot Ltd (ASX: IPL).

The Incitec Pivot share price is up 4.4% today at $3.10. That puts shares back in the green for the full year, up 1%. Incitec Pivot shares also trade on a 4.7% unfranked trailing dividend yield.

And according to RBC, the stock could have a strong run ahead of it. The broker raised Incitec to an outperform rating with a $3.60 price target. That represents a potential upside of more than 16% from current levels.

This brings us to Ventia Services Group Ltd (ASX: VNT), the third ASX All Ords share getting a broker upgrade.

The Venetia share price is up 0.9% at the time of writing at $4.66 a share. That puts the Ventia share price up 67% over 12 months. Ventia shares also trade on a partly franked 4.0% trailing dividend yield.

And RBC believes there are more outsized gains to be had. The broker started Ventia Services at an outperform rating with a $5.25 price target. That represents a potential upside of almost 13% from current levels.

Service Stream Ltd (ASX: SSM) rounds off our list of ASX All Ords shares earning a broker upgrade.

The Service Stream share price is up 2.6% in early afternoon trade today at $1.58. This sees the Service Stream share price up 73% since this time last year. Service Stream shares also trade on a fully franked 2.9% trailing dividend yield.

And RBC thinks this company can deliver another year of strong performance. The broker started Service Stream at an outperform rating with a $1.75 price target. That's almost 11% above the current share price.